mib(n) Tnm Tcl Extension mib(n)_________________________________________________________________NAMEmib - Load and query SNMP MIB definitions.
_________________________________________________________________DESCRIPTION
The mib command allows to load and query definitions con-
tained in SNMP Management Information Base (MIB) specifi-
cations (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 for-
mat/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. sysDe-
scr). However, simple names are only unique for a single
MIB module. A globally unique name is therefore the combi-
nation 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 following sub-identifier is a hexadeci-
mal value. You can also use a dot followed by the 0x pre-
fix. 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 con-
verted 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 COMMANDmib load file
The mib load command loads the MIB definitions con-
tained 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
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mib(n) Tnm Tcl Extension mib(n)
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 cur-
rent 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 plat-
form 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 defini-
tions. 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 associ-
ated with a node in the MIB tree. 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 identi-
fier. 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 identi-
fier. If a label is not unique within the loaded
MIB definitions, the object identifier of the first
matching MIB node will be returned.
mib [-exact] module label
The mib module command returns the name of the mod-
ule 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
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mib(n) Tnm Tcl Extension mib(n)
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-conven-
tion. The mib tc command can be used to get the
underlying base syntax which is used to encode val-
ues 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 formats discussed above.
The -exact option forces strict lookups where it is
not allowed that label contains an instance identi-
fier. The format of the result depends on the for-
mat 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
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mib(n) Tnm Tcl Extension mib(n)
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 formats 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 underly-
ing ASN.1 type, the format string (display hint), a
list of name value pairs used to convert enumera-
tions to integer values, the MIB module which con-
tains 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.
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mib(n) Tnm Tcl Extension mib(n)mib format label value
The mib format command can be used to apply a tex-
tual 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 formats dis-
cussed 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 opera-
tion 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 format rather than the readable represen-
tation. 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 identi-
fier.
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 iden-
tified by label is assigned to varName before the
body is evaluated. 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 ALSOscotty(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>
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