1 | SNMPv2-TC DEFINITIONS ::= BEGIN
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2 |
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3 | IMPORTS
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4 | TimeTicks FROM SNMPv2-SMI;
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5 |
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6 |
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7 | -- definition of textual conventions
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8 |
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9 | TEXTUAL-CONVENTION MACRO ::=
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10 | BEGIN
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11 | TYPE NOTATION ::=
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12 | DisplayPart
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13 | "STATUS" Status
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14 | "DESCRIPTION" Text
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15 | ReferPart
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16 | "SYNTAX" Syntax
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17 |
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18 | VALUE NOTATION ::=
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19 | value(VALUE Syntax) -- adapted ASN.1
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20 |
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21 | DisplayPart ::=
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22 | "DISPLAY-HINT" Text
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23 | | empty
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24 |
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25 | Status ::=
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26 | "current"
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27 | | "deprecated"
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28 | | "obsolete"
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29 |
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30 | ReferPart ::=
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31 | "REFERENCE" Text
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32 | | empty
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33 |
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34 | -- a character string as defined in [2]
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35 | Text ::= value(IA5String)
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36 |
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37 | Syntax ::= -- Must be one of the following:
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38 | -- a base type (or its refinement), or
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39 | -- a BITS pseudo-type
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40 | type
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41 | | "BITS" "{" NamedBits "}"
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42 |
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43 | NamedBits ::= NamedBit
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44 | | NamedBits "," NamedBit
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45 |
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46 | NamedBit ::= identifier "(" number ")" -- number is nonnegative
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47 |
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48 | END
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49 |
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50 |
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51 |
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52 |
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53 | DisplayString ::= TEXTUAL-CONVENTION
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54 | DISPLAY-HINT "255a"
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55 | STATUS current
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56 | DESCRIPTION
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57 | "Represents textual information taken from the NVT ASCII
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58 | character set, as defined in pages 4, 10-11 of RFC 854.
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59 |
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60 | To summarize RFC 854, the NVT ASCII repertoire specifies:
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61 |
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62 | - the use of character codes 0-127 (decimal)
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63 |
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64 | - the graphics characters (32-126) are interpreted as
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65 | US ASCII
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66 |
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67 | - NUL, LF, CR, BEL, BS, HT, VT and FF have the special
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68 | meanings specified in RFC 854
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69 |
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70 | - the other 25 codes have no standard interpretation
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71 |
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72 | - the sequence 'CR LF' means newline
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73 |
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74 | - the sequence 'CR NUL' means carriage-return
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75 |
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76 | - an 'LF' not preceded by a 'CR' means moving to the
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77 | same column on the next line.
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78 |
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79 | - the sequence 'CR x' for any x other than LF or NUL is
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80 | illegal. (Note that this also means that a string may
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81 | end with either 'CR LF' or 'CR NUL', but not with CR.)
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82 |
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83 | Any object defined using this syntax may not exceed 255
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84 | characters in length."
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85 | SYNTAX OCTET STRING (SIZE (0..255))
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86 |
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87 | PhysAddress ::= TEXTUAL-CONVENTION
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88 | DISPLAY-HINT "1x:"
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89 | STATUS current
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90 | DESCRIPTION
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91 | "Represents media- or physical-level addresses."
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92 | SYNTAX OCTET STRING
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93 |
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94 |
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95 | MacAddress ::= TEXTUAL-CONVENTION
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96 | DISPLAY-HINT "1x:"
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97 | STATUS current
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98 | DESCRIPTION
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99 | "Represents an 802 MAC address represented in the
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100 | `canonical' order defined by IEEE 802.1a, i.e., as if it
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101 | were transmitted least significant bit first, even though
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102 | 802.5 (in contrast to other 802.x protocols) requires MAC
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103 | addresses to be transmitted most significant bit first."
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104 | SYNTAX OCTET STRING (SIZE (6))
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105 |
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106 | TruthValue ::= TEXTUAL-CONVENTION
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107 | STATUS current
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108 | DESCRIPTION
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109 | "Represents a boolean value."
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110 | SYNTAX INTEGER { true(1), false(2) }
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111 |
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112 | TestAndIncr ::= TEXTUAL-CONVENTION
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113 | STATUS current
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114 | DESCRIPTION
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115 | "Represents integer-valued information used for atomic
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116 | operations. When the management protocol is used to specify
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117 | that an object instance having this syntax is to be
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118 | modified, the new value supplied via the management protocol
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119 | must precisely match the value presently held by the
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120 | instance. If not, the management protocol set operation
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121 | fails with an error of `inconsistentValue'. Otherwise, if
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122 | the current value is the maximum value of 2^31-1 (2147483647
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123 | decimal), then the value held by the instance is wrapped to
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124 | zero; otherwise, the value held by the instance is
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125 | incremented by one. (Note that regardless of whether the
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126 | management protocol set operation succeeds, the variable-
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127 | binding in the request and response PDUs are identical.)
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128 |
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129 | The value of the ACCESS clause for objects having this
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130 | syntax is either `read-write' or `read-create'. When an
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131 | instance of a columnar object having this syntax is created,
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132 | any value may be supplied via the management protocol.
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133 |
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134 | When the network management portion of the system is re-
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135 | initialized, the value of every object instance having this
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136 | syntax must either be incremented from its value prior to
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137 | the re-initialization, or (if the value prior to the re-
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138 | initialization is unknown) be set to a pseudo-randomly
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139 | generated value."
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140 | SYNTAX INTEGER (0..2147483647)
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141 |
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142 | AutonomousType ::= TEXTUAL-CONVENTION
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143 | STATUS current
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144 | DESCRIPTION
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145 | "Represents an independently extensible type identification
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146 | value. It may, for example, indicate a particular sub-tree
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147 | with further MIB definitions, or define a particular type of
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148 | protocol or hardware."
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149 | SYNTAX OBJECT IDENTIFIER
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150 |
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151 |
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152 | InstancePointer ::= TEXTUAL-CONVENTION
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153 | STATUS obsolete
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154 | DESCRIPTION
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155 | "A pointer to either a specific instance of a MIB object or
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156 | a conceptual row of a MIB table in the managed device. In
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157 | the latter case, by convention, it is the name of the
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158 | particular instance of the first accessible columnar object
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159 | in the conceptual row.
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160 |
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161 | The two uses of this textual convention are replaced by
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162 | VariablePointer and RowPointer, respectively."
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163 | SYNTAX OBJECT IDENTIFIER
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164 |
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165 |
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166 | VariablePointer ::= TEXTUAL-CONVENTION
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167 | STATUS current
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168 | DESCRIPTION
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169 | "A pointer to a specific object instance. For example,
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170 | sysContact.0 or ifInOctets.3."
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171 | SYNTAX OBJECT IDENTIFIER
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172 |
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173 |
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174 | RowPointer ::= TEXTUAL-CONVENTION
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175 | STATUS current
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176 | DESCRIPTION
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177 | "Represents a pointer to a conceptual row. The value is the
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178 | name of the instance of the first accessible columnar object
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179 | in the conceptual row.
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180 |
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181 | For example, ifIndex.3 would point to the 3rd row in the
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182 | ifTable (note that if ifIndex were not-accessible, then
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183 | ifDescr.3 would be used instead)."
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184 | SYNTAX OBJECT IDENTIFIER
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185 |
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186 | RowStatus ::= TEXTUAL-CONVENTION
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187 | STATUS current
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188 | DESCRIPTION
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189 | "The RowStatus textual convention is used to manage the
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190 | creation and deletion of conceptual rows, and is used as the
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191 | value of the SYNTAX clause for the status column of a
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192 | conceptual row (as described in Section 7.7.1 of [2].)
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193 | The status column has six defined values:
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194 |
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195 | - `active', which indicates that the conceptual row is
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196 | available for use by the managed device;
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197 |
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198 | - `notInService', which indicates that the conceptual
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199 | row exists in the agent, but is unavailable for use by
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200 | the managed device (see NOTE below); 'notInService' has
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201 | no implication regarding the internal consistency of
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202 | the row, availability of resources, or consistency with
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203 | the current state of the managed device;
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204 |
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205 | - `notReady', which indicates that the conceptual row
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206 | exists in the agent, but is missing information
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207 | necessary in order to be available for use by the
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208 | managed device (i.e., one or more required columns in
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209 | the conceptual row have not been instanciated);
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210 |
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211 | - `createAndGo', which is supplied by a management
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212 | station wishing to create a new instance of a
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213 | conceptual row and to have its status automatically set
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214 | to active, making it available for use by the managed
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215 | device;
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216 |
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217 | - `createAndWait', which is supplied by a management
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218 | station wishing to create a new instance of a
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219 | conceptual row (but not make it available for use by
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220 | the managed device); and,
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221 |
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222 | - `destroy', which is supplied by a management station
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223 | wishing to delete all of the instances associated with
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224 | an existing conceptual row.
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225 |
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226 | Whereas five of the six values (all except `notReady') may
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227 | be specified in a management protocol set operation, only
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228 | three values will be returned in response to a management
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229 | protocol retrieval operation: `notReady', `notInService' or
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230 | `active'. That is, when queried, an existing conceptual row
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231 | has only three states: it is either available for use by
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232 | the managed device (the status column has value `active');
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233 | it is not available for use by the managed device, though
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234 | the agent has sufficient information to attempt to make it
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235 | so (the status column has value `notInService'); or, it is
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236 | not available for use by the managed device, and an attempt
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237 | to make it so would fail because the agent has insufficient
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238 | information (the state column has value `notReady').
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239 |
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240 | NOTE WELL
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241 |
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242 | This textual convention may be used for a MIB table,
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243 | irrespective of whether the values of that table's
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244 | conceptual rows are able to be modified while it is
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245 | active, or whether its conceptual rows must be taken
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246 | out of service in order to be modified. That is, it is
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247 | the responsibility of the DESCRIPTION clause of the
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248 | status column to specify whether the status column must
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249 | not be `active' in order for the value of some other
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250 | column of the same conceptual row to be modified. If
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251 | such a specification is made, affected columns may be
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252 | changed by an SNMP set PDU if the RowStatus would not
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253 | be equal to `active' either immediately before or after
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254 | processing the PDU. In other words, if the PDU also
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255 | contained a varbind that would change the RowStatus
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256 | value, the column in question may be changed if the
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257 | RowStatus was not equal to `active' as the PDU was
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258 | received, or if the varbind sets the status to a value
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259 | other than 'active'.
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260 |
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261 |
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262 | Also note that whenever any elements of a row exist, the
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263 | RowStatus column must also exist.
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264 |
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265 | To summarize the effect of having a conceptual row with a
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266 | status column having a SYNTAX clause value of RowStatus,
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267 | consider the following state diagram:
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268 |
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269 |
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270 | STATE
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271 | +--------------+-----------+-------------+-------------
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272 | | A | B | C | D
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273 | | |status col.|status column|
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274 | |status column | is | is |status column
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275 | ACTION |does not exist| notReady | notInService| is active
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276 | --------------+--------------+-----------+-------------+-------------
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277 | set status |noError ->D|inconsist- |inconsistent-|inconsistent-
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278 | column to | or | entValue| Value| Value
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279 | createAndGo |inconsistent- | | |
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280 | | Value| | |
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281 | --------------+--------------+-----------+-------------+-------------
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282 | set status |noError see 1|inconsist- |inconsistent-|inconsistent-
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283 | column to | or | entValue| Value| Value
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284 | createAndWait |wrongValue | | |
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285 | --------------+--------------+-----------+-------------+-------------
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286 | set status |inconsistent- |inconsist- |noError |noError
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287 | column to | Value| entValue| |
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288 | active | | | |
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289 | | | or | |
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290 | | | | |
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291 | | |see 2 ->D|see 8 ->D| ->D
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292 | --------------+--------------+-----------+-------------+-------------
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293 | set status |inconsistent- |inconsist- |noError |noError ->C
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294 | column to | Value| entValue| |
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295 | notInService | | | |
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296 | | | or | | or
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297 | | | | |
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298 | | |see 3 ->C| ->C|see 6
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299 | --------------+--------------+-----------+-------------+-------------
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300 | set status |noError |noError |noError |noError ->A
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301 | column to | | | | or
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302 | destroy | ->A| ->A| ->A|see 7
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303 | --------------+--------------+-----------+-------------+-------------
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304 | set any other |see 4 |noError |noError |see 5
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305 | column to some| | | |
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306 | value | | see 1| ->C| ->D
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307 | --------------+--------------+-----------+-------------+-------------
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308 |
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309 | (1) goto B or C, depending on information available to the
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310 | agent.
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311 |
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312 | (2) if other variable bindings included in the same PDU,
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313 | provide values for all columns which are missing but
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314 | required, and all columns have acceptable values, then
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315 | return noError and goto D.
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316 |
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317 | (3) if other variable bindings included in the same PDU,
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318 | provide legal values for all columns which are missing but
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319 | required, then return noError and goto C.
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320 |
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321 | (4) at the discretion of the agent, the return value may be
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322 | either:
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323 |
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324 | inconsistentName: because the agent does not choose to
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325 | create such an instance when the corresponding
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326 | RowStatus instance does not exist, or
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327 |
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328 | inconsistentValue: if the supplied value is
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329 | inconsistent with the state of some other MIB object's
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330 | value, or
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331 |
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332 | noError: because the agent chooses to create the
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333 | instance.
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334 |
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335 | If noError is returned, then the instance of the status
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336 | column must also be created, and the new state is B or C,
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337 | depending on the information available to the agent. If
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338 | inconsistentName or inconsistentValue is returned, the row
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339 | remains in state A.
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340 |
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341 | (5) depending on the MIB definition for the column/table,
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342 | either noError or inconsistentValue may be returned.
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343 |
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344 | (6) the return value can indicate one of the following
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345 | errors:
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346 |
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347 | wrongValue: because the agent does not support
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348 | notInService (e.g., an agent which does not support
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349 | createAndWait), or
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350 |
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351 | inconsistentValue: because the agent is unable to take
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352 | the row out of service at this time, perhaps because it
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353 | is in use and cannot be de-activated.
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354 |
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355 | (7) the return value can indicate the following error:
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356 |
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357 | inconsistentValue: because the agent is unable to
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358 | remove the row at this time, perhaps because it is in
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359 | use and cannot be de-activated.
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360 |
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361 | (8) the transition to D can fail, e.g., if the values of the
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362 | conceptual row are inconsistent, then the error code would
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363 | be inconsistentValue.
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364 |
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365 | NOTE: Other processing of (this and other varbinds of) the
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366 | set request may result in a response other than noError
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367 | being returned, e.g., wrongValue, noCreation, etc.
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368 |
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369 |
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370 | Conceptual Row Creation
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371 |
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372 | There are four potential interactions when creating a
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373 | conceptual row: selecting an instance-identifier which is
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374 | not in use; creating the conceptual row; initializing any
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375 | objects for which the agent does not supply a default; and,
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376 | making the conceptual row available for use by the managed
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377 | device.
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378 |
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379 | Interaction 1: Selecting an Instance-Identifier
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380 |
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381 | The algorithm used to select an instance-identifier varies
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382 | for each conceptual row. In some cases, the instance-
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383 | identifier is semantically significant, e.g., the
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384 | destination address of a route, and a management station
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385 | selects the instance-identifier according to the semantics.
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386 |
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387 | In other cases, the instance-identifier is used solely to
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388 | distinguish conceptual rows, and a management station
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389 | without specific knowledge of the conceptual row might
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390 | examine the instances present in order to determine an
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391 | unused instance-identifier. (This approach may be used, but
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392 | it is often highly sub-optimal; however, it is also a
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393 | questionable practice for a naive management station to
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394 | attempt conceptual row creation.)
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395 |
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396 | Alternately, the MIB module which defines the conceptual row
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397 | might provide one or more objects which provide assistance
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398 | in determining an unused instance-identifier. For example,
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399 | if the conceptual row is indexed by an integer-value, then
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400 | an object having an integer-valued SYNTAX clause might be
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401 | defined for such a purpose, allowing a management station to
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402 | issue a management protocol retrieval operation. In order
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403 | to avoid unnecessary collisions between competing management
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404 | stations, `adjacent' retrievals of this object should be
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405 | different.
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406 |
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407 | Finally, the management station could select a pseudo-random
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408 | number to use as the index. In the event that this index
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409 | was already in use and an inconsistentValue was returned in
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410 | response to the management protocol set operation, the
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411 | management station should simply select a new pseudo-random
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412 | number and retry the operation.
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413 |
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414 | A MIB designer should choose between the two latter
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415 | algorithms based on the size of the table (and therefore the
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416 | efficiency of each algorithm). For tables in which a large
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417 | number of entries are expected, it is recommended that a MIB
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418 | object be defined that returns an acceptable index for
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419 | creation. For tables with small numbers of entries, it is
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420 | recommended that the latter pseudo-random index mechanism be
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421 | used.
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422 |
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423 | Interaction 2: Creating the Conceptual Row
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424 |
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425 | Once an unused instance-identifier has been selected, the
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426 | management station determines if it wishes to create and
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427 | activate the conceptual row in one transaction or in a
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428 | negotiated set of interactions.
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429 |
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430 | Interaction 2a: Creating and Activating the Conceptual Row
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431 |
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432 | The management station must first determine the column
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433 | requirements, i.e., it must determine those columns for
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434 | which it must or must not provide values. Depending on the
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435 | complexity of the table and the management station's
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436 | knowledge of the agent's capabilities, this determination
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437 | can be made locally by the management station. Alternately,
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438 | the management station issues a management protocol get
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439 | operation to examine all columns in the conceptual row that
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440 | it wishes to create. In response, for each column, there
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441 | are three possible outcomes:
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442 |
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443 | - a value is returned, indicating that some other
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444 | management station has already created this conceptual
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445 | row. We return to interaction 1.
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446 |
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447 | - the exception `noSuchInstance' is returned,
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448 | indicating that the agent implements the object-type
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449 | associated with this column, and that this column in at
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450 | least one conceptual row would be accessible in the MIB
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451 | view used by the retrieval were it to exist. For those
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452 | columns to which the agent provides read-create access,
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453 | the `noSuchInstance' exception tells the management
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454 | station that it should supply a value for this column
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455 | when the conceptual row is to be created.
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456 |
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457 | - the exception `noSuchObject' is returned, indicating
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458 | that the agent does not implement the object-type
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459 | associated with this column or that there is no
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460 | conceptual row for which this column would be
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461 | accessible in the MIB view used by the retrieval. As
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462 | such, the management station can not issue any
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463 | management protocol set operations to create an
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464 | instance of this column.
|
---|
465 |
|
---|
466 | Once the column requirements have been determined, a
|
---|
467 | management protocol set operation is accordingly issued.
|
---|
468 | This operation also sets the new instance of the status
|
---|
469 | column to `createAndGo'.
|
---|
470 |
|
---|
471 | When the agent processes the set operation, it verifies that
|
---|
472 | it has sufficient information to make the conceptual row
|
---|
473 | available for use by the managed device. The information
|
---|
474 | available to the agent is provided by two sources: the
|
---|
475 | management protocol set operation which creates the
|
---|
476 | conceptual row, and, implementation-specific defaults
|
---|
477 | supplied by the agent (note that an agent must provide
|
---|
478 | implementation-specific defaults for at least those objects
|
---|
479 | which it implements as read-only). If there is sufficient
|
---|
480 | information available, then the conceptual row is created, a
|
---|
481 | `noError' response is returned, the status column is set to
|
---|
482 | `active', and no further interactions are necessary (i.e.,
|
---|
483 | interactions 3 and 4 are skipped). If there is insufficient
|
---|
484 | information, then the conceptual row is not created, and the
|
---|
485 | set operation fails with an error of `inconsistentValue'.
|
---|
486 | On this error, the management station can issue a management
|
---|
487 | protocol retrieval operation to determine if this was
|
---|
488 | because it failed to specify a value for a required column,
|
---|
489 | or, because the selected instance of the status column
|
---|
490 | already existed. In the latter case, we return to
|
---|
491 | interaction 1. In the former case, the management station
|
---|
492 | can re-issue the set operation with the additional
|
---|
493 | information, or begin interaction 2 again using
|
---|
494 | `createAndWait' in order to negotiate creation of the
|
---|
495 | conceptual row.
|
---|
496 |
|
---|
497 | NOTE WELL
|
---|
498 |
|
---|
499 | Regardless of the method used to determine the column
|
---|
500 | requirements, it is possible that the management
|
---|
501 | station might deem a column necessary when, in fact,
|
---|
502 | the agent will not allow that particular columnar
|
---|
503 | instance to be created or written. In this case, the
|
---|
504 | management protocol set operation will fail with an
|
---|
505 | error such as `noCreation' or `notWritable'. In this
|
---|
506 | case, the management station decides whether it needs
|
---|
507 | to be able to set a value for that particular columnar
|
---|
508 | instance. If not, the management station re-issues the
|
---|
509 | management protocol set operation, but without setting
|
---|
510 | a value for that particular columnar instance;
|
---|
511 | otherwise, the management station aborts the row
|
---|
512 | creation algorithm.
|
---|
513 |
|
---|
514 | Interaction 2b: Negotiating the Creation of the Conceptual
|
---|
515 | Row
|
---|
516 |
|
---|
517 | The management station issues a management protocol set
|
---|
518 | operation which sets the desired instance of the status
|
---|
519 | column to `createAndWait'. If the agent is unwilling to
|
---|
520 | process a request of this sort, the set operation fails with
|
---|
521 | an error of `wrongValue'. (As a consequence, such an agent
|
---|
522 | must be prepared to accept a single management protocol set
|
---|
523 | operation, i.e., interaction 2a above, containing all of the
|
---|
524 | columns indicated by its column requirements.) Otherwise,
|
---|
525 | the conceptual row is created, a `noError' response is
|
---|
526 | returned, and the status column is immediately set to either
|
---|
527 | `notInService' or `notReady', depending on whether it has
|
---|
528 | sufficient information to (attempt to) make the conceptual
|
---|
529 | row available for use by the managed device. If there is
|
---|
530 | sufficient information available, then the status column is
|
---|
531 | set to `notInService'; otherwise, if there is insufficient
|
---|
532 | information, then the status column is set to `notReady'.
|
---|
533 | Regardless, we proceed to interaction 3.
|
---|
534 |
|
---|
535 | Interaction 3: Initializing non-defaulted Objects
|
---|
536 |
|
---|
537 | The management station must now determine the column
|
---|
538 | requirements. It issues a management protocol get operation
|
---|
539 | to examine all columns in the created conceptual row. In
|
---|
540 | the response, for each column, there are three possible
|
---|
541 | outcomes:
|
---|
542 |
|
---|
543 | - a value is returned, indicating that the agent
|
---|
544 | implements the object-type associated with this column
|
---|
545 | and had sufficient information to provide a value. For
|
---|
546 | those columns to which the agent provides read-create
|
---|
547 | access (and for which the agent allows their values to
|
---|
548 | be changed after their creation), a value return tells
|
---|
549 | the management station that it may issue additional
|
---|
550 | management protocol set operations, if it desires, in
|
---|
551 | order to change the value associated with this column.
|
---|
552 |
|
---|
553 | - the exception `noSuchInstance' is returned,
|
---|
554 | indicating that the agent implements the object-type
|
---|
555 | associated with this column, and that this column in at
|
---|
556 | least one conceptual row would be accessible in the MIB
|
---|
557 | view used by the retrieval were it to exist. However,
|
---|
558 | the agent does not have sufficient information to
|
---|
559 | provide a value, and until a value is provided, the
|
---|
560 | conceptual row may not be made available for use by the
|
---|
561 | managed device. For those columns to which the agent
|
---|
562 | provides read-create access, the `noSuchInstance'
|
---|
563 | exception tells the management station that it must
|
---|
564 | issue additional management protocol set operations, in
|
---|
565 | order to provide a value associated with this column.
|
---|
566 |
|
---|
567 | - the exception `noSuchObject' is returned, indicating
|
---|
568 | that the agent does not implement the object-type
|
---|
569 | associated with this column or that there is no
|
---|
570 | conceptual row for which this column would be
|
---|
571 | accessible in the MIB view used by the retrieval. As
|
---|
572 | such, the management station can not issue any
|
---|
573 | management protocol set operations to create an
|
---|
574 | instance of this column.
|
---|
575 |
|
---|
576 | If the value associated with the status column is
|
---|
577 | `notReady', then the management station must first deal with
|
---|
578 | all `noSuchInstance' columns, if any. Having done so, the
|
---|
579 | value of the status column becomes `notInService', and we
|
---|
580 | proceed to interaction 4.
|
---|
581 |
|
---|
582 | Interaction 4: Making the Conceptual Row Available
|
---|
583 |
|
---|
584 | Once the management station is satisfied with the values
|
---|
585 | associated with the columns of the conceptual row, it issues
|
---|
586 | a management protocol set operation to set the status column
|
---|
587 | to `active'. If the agent has sufficient information to
|
---|
588 | make the conceptual row available for use by the managed
|
---|
589 | device, the management protocol set operation succeeds (a
|
---|
590 | `noError' response is returned). Otherwise, the management
|
---|
591 | protocol set operation fails with an error of
|
---|
592 | `inconsistentValue'.
|
---|
593 |
|
---|
594 | NOTE WELL
|
---|
595 |
|
---|
596 | A conceptual row having a status column with value
|
---|
597 | `notInService' or `notReady' is unavailable to the
|
---|
598 | managed device. As such, it is possible for the
|
---|
599 | managed device to create its own instances during the
|
---|
600 | time between the management protocol set operation
|
---|
601 | which sets the status column to `createAndWait' and the
|
---|
602 | management protocol set operation which sets the status
|
---|
603 | column to `active'. In this case, when the management
|
---|
604 | protocol set operation is issued to set the status
|
---|
605 | column to `active', the values held in the agent
|
---|
606 | supersede those used by the managed device.
|
---|
607 |
|
---|
608 | If the management station is prevented from setting the
|
---|
609 | status column to `active' (e.g., due to management station
|
---|
610 | or network failure) the conceptual row will be left in the
|
---|
611 | `notInService' or `notReady' state, consuming resources
|
---|
612 | indefinitely. The agent must detect conceptual rows that
|
---|
613 | have been in either state for an abnormally long period of
|
---|
614 | time and remove them. It is the responsibility of the
|
---|
615 | DESCRIPTION clause of the status column to indicate what an
|
---|
616 | abnormally long period of time would be. This period of
|
---|
617 | time should be long enough to allow for human response time
|
---|
618 | (including `think time') between the creation of the
|
---|
619 | conceptual row and the setting of the status to `active'.
|
---|
620 | In the absence of such information in the DESCRIPTION
|
---|
621 | clause, it is suggested that this period be approximately 5
|
---|
622 | minutes in length. This removal action applies not only to
|
---|
623 | newly-created rows, but also to previously active rows which
|
---|
624 | are set to, and left in, the notInService state for a
|
---|
625 | prolonged period exceeding that which is considered normal
|
---|
626 | for such a conceptual row.
|
---|
627 |
|
---|
628 | Conceptual Row Suspension
|
---|
629 |
|
---|
630 | When a conceptual row is `active', the management station
|
---|
631 | may issue a management protocol set operation which sets the
|
---|
632 | instance of the status column to `notInService'. If the
|
---|
633 | agent is unwilling to do so, the set operation fails with an
|
---|
634 | error of `wrongValue' or `inconsistentValue'. Otherwise,
|
---|
635 | the conceptual row is taken out of service, and a `noError'
|
---|
636 | response is returned. It is the responsibility of the
|
---|
637 | DESCRIPTION clause of the status column to indicate under
|
---|
638 | what circumstances the status column should be taken out of
|
---|
639 | service (e.g., in order for the value of some other column
|
---|
640 | of the same conceptual row to be modified).
|
---|
641 |
|
---|
642 |
|
---|
643 | Conceptual Row Deletion
|
---|
644 |
|
---|
645 | For deletion of conceptual rows, a management protocol set
|
---|
646 | operation is issued which sets the instance of the status
|
---|
647 | column to `destroy'. This request may be made regardless of
|
---|
648 | the current value of the status column (e.g., it is possible
|
---|
649 | to delete conceptual rows which are either `notReady',
|
---|
650 | `notInService' or `active'.) If the operation succeeds,
|
---|
651 | then all instances associated with the conceptual row are
|
---|
652 | immediately removed."
|
---|
653 | SYNTAX INTEGER {
|
---|
654 | -- the following two values are states:
|
---|
655 | -- these values may be read or written
|
---|
656 | active(1),
|
---|
657 | notInService(2),
|
---|
658 |
|
---|
659 | -- the following value is a state:
|
---|
660 | -- this value may be read, but not written
|
---|
661 | notReady(3),
|
---|
662 |
|
---|
663 | -- the following three values are
|
---|
664 | -- actions: these values may be written,
|
---|
665 | -- but are never read
|
---|
666 | createAndGo(4),
|
---|
667 | createAndWait(5),
|
---|
668 | destroy(6)
|
---|
669 | }
|
---|
670 |
|
---|
671 | TimeStamp ::= TEXTUAL-CONVENTION
|
---|
672 | STATUS current
|
---|
673 | DESCRIPTION
|
---|
674 | "The value of the sysUpTime object at which a specific
|
---|
675 | occurrence happened. The specific occurrence must be
|
---|
676 | defined in the description of any object defined using this
|
---|
677 | type.
|
---|
678 |
|
---|
679 | If sysUpTime is reset to zero as a result of a re-
|
---|
680 | initialization of the network management (sub)system, then
|
---|
681 | the values of all TimeStamp objects are also reset.
|
---|
682 | However, after approximately 497 days without a re-
|
---|
683 | initialization, the sysUpTime object will reach 2^^32-1 and
|
---|
684 | then increment around to zero; in this case, existing values
|
---|
685 | of TimeStamp objects do not change. This can lead to
|
---|
686 | ambiguities in the value of TimeStamp objects."
|
---|
687 | SYNTAX TimeTicks
|
---|
688 |
|
---|
689 |
|
---|
690 | TimeInterval ::= TEXTUAL-CONVENTION
|
---|
691 | STATUS current
|
---|
692 | DESCRIPTION
|
---|
693 | "A period of time, measured in units of 0.01 seconds."
|
---|
694 | SYNTAX INTEGER (0..2147483647)
|
---|
695 |
|
---|
696 | DateAndTime ::= TEXTUAL-CONVENTION
|
---|
697 | DISPLAY-HINT "2d-1d-1d,1d:1d:1d.1d,1a1d:1d"
|
---|
698 | STATUS current
|
---|
699 | DESCRIPTION
|
---|
700 | "A date-time specification.
|
---|
701 |
|
---|
702 | field octets contents range
|
---|
703 | ----- ------ -------- -----
|
---|
704 | 1 1-2 year* 0..65536
|
---|
705 | 2 3 month 1..12
|
---|
706 | 3 4 day 1..31
|
---|
707 | 4 5 hour 0..23
|
---|
708 | 5 6 minutes 0..59
|
---|
709 | 6 7 seconds 0..60
|
---|
710 | (use 60 for leap-second)
|
---|
711 | 7 8 deci-seconds 0..9
|
---|
712 | 8 9 direction from UTC '+' / '-'
|
---|
713 | 9 10 hours from UTC* 0..13
|
---|
714 | 10 11 minutes from UTC 0..59
|
---|
715 |
|
---|
716 | * Notes:
|
---|
717 | - the value of year is in network-byte order
|
---|
718 | - daylight saving time in New Zealand is +13
|
---|
719 |
|
---|
720 | For example, Tuesday May 26, 1992 at 1:30:15 PM EDT would be
|
---|
721 | displayed as:
|
---|
722 |
|
---|
723 | 1992-5-26,13:30:15.0,-4:0
|
---|
724 |
|
---|
725 | Note that if only local time is known, then timezone
|
---|
726 | information (fields 8-10) is not present."
|
---|
727 | SYNTAX OCTET STRING (SIZE (8 | 11))
|
---|
728 |
|
---|
729 |
|
---|
730 | StorageType ::= TEXTUAL-CONVENTION
|
---|
731 | STATUS current
|
---|
732 | DESCRIPTION
|
---|
733 | "Describes the memory realization of a conceptual row. A
|
---|
734 | row which is volatile(2) is lost upon reboot. A row which
|
---|
735 | is either nonVolatile(3), permanent(4) or readOnly(5), is
|
---|
736 | backed up by stable storage. A row which is permanent(4)
|
---|
737 | can be changed but not deleted. A row which is readOnly(5)
|
---|
738 | cannot be changed nor deleted.
|
---|
739 |
|
---|
740 | If the value of an object with this syntax is either
|
---|
741 | permanent(4) or readOnly(5), it cannot be written.
|
---|
742 | Conversely, if the value is either other(1), volatile(2) or
|
---|
743 | nonVolatile(3), it cannot be modified to be permanent(4) or
|
---|
744 | readOnly(5). (All illegal modifications result in a
|
---|
745 | 'wrongValue' error.)
|
---|
746 |
|
---|
747 | Every usage of this textual convention is required to
|
---|
748 | specify the columnar objects which a permanent(4) row must
|
---|
749 | at a minimum allow to be writable."
|
---|
750 | SYNTAX INTEGER {
|
---|
751 | other(1), -- eh?
|
---|
752 | volatile(2), -- e.g., in RAM
|
---|
753 | nonVolatile(3), -- e.g., in NVRAM
|
---|
754 | permanent(4), -- e.g., partially in ROM
|
---|
755 | readOnly(5) -- e.g., completely in ROM
|
---|
756 | }
|
---|
757 |
|
---|
758 | TDomain ::= TEXTUAL-CONVENTION
|
---|
759 | STATUS current
|
---|
760 | DESCRIPTION
|
---|
761 | "Denotes a kind of transport service.
|
---|
762 |
|
---|
763 | Some possible values, such as snmpUDPDomain, are defined in
|
---|
764 | the SNMPv2-TM MIB module. Other possible values are defined
|
---|
765 | in other MIB modules."
|
---|
766 | REFERENCE "The SNMPv2-TM MIB module is defined in RFC 1906."
|
---|
767 | SYNTAX OBJECT IDENTIFIER
|
---|
768 |
|
---|
769 |
|
---|
770 | TAddress ::= TEXTUAL-CONVENTION
|
---|
771 | STATUS current
|
---|
772 | DESCRIPTION
|
---|
773 | "Denotes a transport service address.
|
---|
774 |
|
---|
775 | A TAddress value is always interpreted within the context of a
|
---|
776 | TDomain value. Thus, each definition of a TDomain value must
|
---|
777 | be accompanied by a definition of a textual convention for use
|
---|
778 | with that TDomain. Some possible textual conventions, such as
|
---|
779 | SnmpUDPAddress for snmpUDPDomain, are defined in the SNMPv2-TM
|
---|
780 | MIB module. Other possible textual conventions are defined in
|
---|
781 | other MIB modules."
|
---|
782 | REFERENCE "The SNMPv2-TM MIB module is defined in RFC 1906."
|
---|
783 | SYNTAX OCTET STRING (SIZE (1..255))
|
---|
784 |
|
---|
785 |
|
---|
786 | END
|
---|