mib(n) Tnm Tcl Extension mib(n)
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NAME
mib - Load and query SNMP MIB definitions.
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DESCRIPTION
The mib command allows to load and query definitions contained in SNMP Management Information Base (MIB) specifications (RFC 1155, RFC
1212, RFC 1902 and RFC 1903). Queries are usually formulated for a specific node in the global MIB tree. The mib command also allows to
format/scan MIB values from/to their underlying primitive representation.
MIB NODE NAMES
A MIB node is either identified by the globally unique object identifier in dotted notation (e.g. 1.3.6.1.2.1.1.1) or by its descriptive
name (e.g. sysDescr). However, simple names are only unique for a single MIB module. A globally unique name is therefore the combination of
the MIB module name and the name of a MIB node defined in the module (e.g. SNMPv2-MIB!sysDescr). The ! character separates the optional MIB
module name from the node name.
It is also legal to have hexadecimal sub-identifier in an object identifier. A colon instead of a dot is used to indicate that the follow-
ing sub-identifier is a hexadecimal value. You can also use a dot followed by the 0x prefix. This is useful to encode character strings in
an object identifier. As an example, the object identifier 1.3.6.1.4.1.0x627:74:75:62:73 will be accepted and converted to
1.3.6.1.4.1.1575.116.117.98.115.
It is suggested to use the object identifier notation whenever possible in scripts because it is globally unique and fast. Globally unique
names (like SNMPv2-MIB!sysDescr) are also a good and fast choice. Simple names may lead to ambiguities and can result is slower lookups if
the name can not be found in the underlying hash table. Composed simple names (like system.sysDescr) make ambiguities less likely but they
may cause substantial overhead.
MIB COMMAND
mib load file
The mib load command loads the MIB definitions contained in file. The file should contain a valid MIB definition. The built-in
parser reads the file. Parsing errors are written to stderr. The MIB file is usually located at the file system position defined by
the file argument. However, if file is a simple file name and it does not exist in the current directory, than it will be searched
in $tnm(library)/site and $tnm(library)/mibs in this order. A condensed format of the MIB definition is saved in a platform specific
sub-directory below $tnm(library) to speed up future load commands. Note, this requires write permissions for the platform specific
sub-directory.
The Tnm extension automatically loads all MIB files named in the global Tcl variable $tnm(mibs). This allows to pre-define a set of
useful MIB definitions. The default is the set of IETF MIBs. It is possible to bypass the auto-loading mechanism if the first mib
command is a mib load command. Note that the snmp command may also invoke mib commands.
mib [-exact] name label
The mib name command returns the short name associated with a node in the MIB tree. The label may be a node name in one of the for-
mats discussed above. The -exact option forces strict lookups where it is not allowed that label contains an instance identifier.
For example, mib name 1.3.6.1.2.1.1.3.0 will return sysUpTime.0 while mib -exact name 1.3.6.1.2.1.1.3.0 will fail.
mib [-exact] oid label
The mib oid command is the counterpart to the mib name command and returns the object identifier of the MIB node identified by
label. The label may be a node name in one of the formats discussed above. The -exact option forces strict lookups where it is not
allowed that label contains an instance identifier. If a label is not unique within the loaded MIB definitions, the object identi-
fier of the first matching MIB node will be returned.
mib [-exact] module label
The mib module command returns the name of the module which defines the MIB node identified by label. The label may be a node name
in one of the formats discussed above. The -exact option forces strict lookups where it is not allowed that label contains an
instance identifier.
mib [-exact] macro label
The mib macro command returns the name of the ASN.1 macro which has been used to define the MIB node identified by label. The label
may be a node name in one of the formats discussed above. The -exact option forces strict lookups where it is not allowed that label
contains an instance identifier.
mib [-exact] syntax label
The mib syntax command returns the ASN.1 syntax associated with a MIB node or an empty string if the node identified by label has no
associated ASN.1 syntax. The label may be a node name in one of the formats discussed above. The -exact option forces strict lookups
where it is not allowed that label contains an instance identifier. The syntax name returned is the syntax as defined in the macro.
This might be the name of a textual-convention. The mib tc command can be used to get the underlying base syntax which is used to
encode values on the network.
mib [-exact] description label
The mib description command returns the textual description of the MIB node identified by label. The label may be a node name in one
of the formats discussed above. The -exact option forces strict lookups where it is not allowed that label contains an instance
identifier.
mib [-exact] successor label
The mib successor command returns a list of all known successors of the MIB node identified by label. The label may be a node name
in one of the formats discussed above. The -exact option forces strict lookups where it is not allowed that label contains an
instance identifier. The format of the result depends on the format of label: If label is an object identifier, then the result will
be a list of object identifier. The result is a list of names if label is a name of a MIB node.
mib [-exact] parent label
The mib parent command returns the parent node of the MIB node identified by label. The label may be a node name in one of the for-
mats discussed above. The -exact option forces strict lookups where it is not allowed that label contains an instance identifier.
The format of the result depends on the format of label: If label is an object identifier, then the result is the object identifier
of the parent node. The result is the name of the parent node if label is a name of a MIB node.
mib [-exact] access label
The mib access command returns the max-access for a MIB node or an empty string if there is no access associated with the MIB node
identified by label. The label may be a node name in one of the formats discussed above. The -exact option forces strict lookups
where it is not allowed that label contains an instance identifier. The returned access mode is one of the values not-accessible,
read-only, read-create, read-write, write-only.
mib [-exact] index label
The mib index command returns the list of MIB names which are used as a key in a conceptual table or an empty result if the MIB node
identified by label does not correspond to a MIB table. The label may be a node name in one of the formats discussed above. The
-exact option forces strict lookups where it is not allowed that label contains an instance identifier.
mib [-exact] tc label
The mib tc command returns a Tcl list which describes the textual convention associated with the MIB node identified by label. The
result is an empty string if the MIB node does not make use of a textual convention. The label may be a node name in one of the for-
mats discussed above. The -exact option forces strict lookups where it is not allowed that label contains an instance identifier.
The list contains the following elements: the name of the textual convention, the name of the underlying ASN.1 type, the format
string (display hint), a list of name value pairs used to convert enumerations to integer values, the MIB module which contains the
definition of the textual convention and the file which contains the definition.
mib [-exact] file label
The mib file command returns the file name that contains the definition of the MIB node identified by label. The label may be a node
name in one of the formats discussed above. The -exact option forces strict lookups where it is not allowed that label contains an
instance identifier.
mib format label value
The mib format command can be used to apply a textual convention that is defined for the MIB node identified by label to value. This
command is used internally to return readable values for SNMP request and may be helpful in situations where it is appropriate to
apply these formating rules directly. The mib format command can be used to render integer enumerations, to apply display hints, to
render time tick values and to convert object identifier into globally unique names. The label may be a node name in one of the for-
mats discussed above. The -exact option forces strict lookups where it is not allowed that label contains an instance identifier.
mib scan label value
The mib scan command implements the inverse operation for the mib format command described above. It converts a rendered value into
the underlying base string representation. This command may be useful in situations where you want to operate on the primitive for-
mat rather than the readable representation. The mib scan command returns the value unaltered if no conversions apply. The label may
be a node name in one of the formats discussed above. The -exact option forces strict lookups where it is not allowed that label
contains an instance identifier.
mib walk varName label body
The mib walk command evaluates the Tcl script body for each known MIB node below the node identified by label. The mib walk command
allows to walk entire MIB subtrees. Every nodes in a subtree identified by label is assigned to varName before the body is evalu-
ated. The value assigned to varName depends on the format of label: If label is an object identifier, then the value will be an
object identifier. The value of varName is the name of a MIB node if label is a name of a MIB node.
SEE ALSO
scotty(1), Tnm(n), Tcl(n)
AUTHORS
Juergen Schoenwaelder <schoenw@cs.utwente.nl>
Sven Schmidt <vschmidt@ibr.cs.tu-bs.de>
Erik Schoenfelder <schoenfr@gaertner.de>
Tnm mib(n)