SNMPCMD

or tcpv6 or tcpipv6 hostname[:port] or IPv6-address:port or ’[’IPv6-address’]’[:port]

Note that <transport-specifier> strings are case-insensitive so that, for example, "tcp" and "TCP" are equivalent. Here are some examples, along with their interpretation:

hostname:161

perform query using UDP/IPv4 datagrams to hostname on port 161. The ":161" is redundant here since that is the default SNMP port in any case.

udp:hostname

identical to the previous specification. The "udp:" is redundant here since UDP/IPv4 is the default transport.

TCP:hostname:1161

connect to hostname on port 1161 using TCP/IPv4 and perform query over that connection.

ipx::00D0B7AAE308

perform query using IPX datagrams to node number 00D0B7AAE308 on the default network, and using the default IPX port of 36879 (900F hexadecimal), as suggested in RFC 1906.

ipx:0AE43409:00D0B721C6C0/1161

perform query using IPX datagrams to port 1161 on node number 00D0B721C6C0 on network number 0AE43409.

unix:/tmp/local-agent

connect to the Unix domain socket /tmp/local-agent, and perform the query over that connection.

/tmp/local-agent

identical to the previous specification, since the Unix domain is the default transport iff the first character of the <transport-address> is a ’/’.

alias:myname

perform a connection to the myname alias which needs to be defined in the snmp.conf file using a line like " alias myname udp:127.0.0.1:9161 ". Any type of transport definition can be used as the alias expansion parameter. Aliases are particularly useful for using repeated complex transport strings.

AAL5PVC:100

perform the query using AAL5 PDUs sent on the permanent virtual circuit with VPI=0 and VCI=100 (decimal) on the first ATM adapter in the machine.

PVC:1.10.32

perform the query using AAL5 PDUs sent on the permanent virtual circuit with VPI=10 (decimal) and VCI=32 (decimal) on the second ATM adapter in the machine. Note that "PVC" is a synonym for "AAL5PVC".

udp6:hostname:10161

perform the query using UDP/IPv6 datagrams to port 10161 on hostname (which will be looked up as an AAAA record).

UDP6:[fe80::2d0:b7ff:fe21:c6c0]

perform the query using UDP/IPv6 datagrams to port 161 at address fe80::2d0:b7ff:fe21:c6c0.

tcpipv6:[::1]:1611

connect to port 1611 on the local host (::1 in IPv6 parlance) using TCP/IPv6 and perform query over that connection.

dtlsudp:hostname:9161

Connects using SNMP over DTLS/UDP as documented by the ISMS working group (RFCs not yet published as of this date). This will require that the TSM security model is in use (--defSecurityModel=tsm) and that the defX509ServerCerts, defX509ClientPriv, and defX509ClientPub configuration tokens have been set.

ssh:hostname:22

Connects using SNMP over SSH as documented by the ISMS working group (RFCs not yet published as of this date). This will require that the TSM security model is in use (--defSecurityModel=tsm).

Note that not all the transport domains listed above will always be available; for instance, hosts with no IPv6 support will not be able to use udp6 transport addresses, and attempts to do so will result in the error "Unknown host". Likewise, since AAL5 PVC support is only currently available on Linux, it will fail with the same error on other platforms.

The Net-SNMP MIB parser mostly adheres to the Structure of Management Information (SMI). As that specification has changed through time, and in recognition of the (ahem) diversity in compliance expressed in MIB files, additional options provide more flexibility in reading MIB files.

-Pc

Toggles whether ASN.1 comments should extend to the end of the MIB source line. Strictly speaking, a second appearance of "--" should terminate the comment, but this breaks some MIB files. The default behaviour (to interpret comments correctly) can also be set with the configuration token commentToEOL.

-Pd

Disables the loading of MIB object DESCRIPTIONs when parsing MIB files. This reduces the amount of memory used by the running application.

-Pe

Toggles whether to show errors encountered when parsing MIB files. These include references to IMPORTed modules and MIB objects that cannot be located in the MIB directory search list. The default behaviour can also be set with the configuration token showMibErrors.

-PR

If the same MIB object (parent name and sub-identifier) appears multiple times in the list of MIB definitions loaded, use the last version to be read in. By default, the first version will be used, and any duplicates discarded. This behaviour can also be set with the configuration token mibReplaceWithLatest.

Such ordering is normally only relevant if there are two MIB files with conflicting object definitions for the same OID (or different revisions of the same basic MIB object).

-Pu

Toggles whether to allow the underline character in MIB object names and other symbols. Strictly speaking, this is not valid SMI syntax, but some vendor MIB files define such names. The default behaviour can also be set with the configuration token mibAllowUnderline.

-Pw

Show various warning messages in parsing MIB files and building the overall OID tree. This can also be set with the configuration directive mibWarningLevel 1

-PW

Show some additional warning messages, mostly relating to parsing individual MIB objects. This can also be set with the configuration directive mibWarningLevel 2

The format of the output from SNMP commands can be controlled using various parameters of the -O flag. The effects of these sub-options can be seen by comparison with the following default output (unless otherwise specified):

$ snmpget -c public -v 1 localhost sysUpTime.0
SNMPv2-MIB::sysUpTime.0 = Timeticks: (14096763) 1 day, 15:09:27.63

-Oa

Display string values as ASCII strings (unless there is a DISPLAY-HINT defined for the corresponding MIB object). By default, the library attempts to determine whether the value is a printable or binary string, and displays it accordingly.

This option does not affect objects that do have a Display Hint.

-Ob

Display table indexes numerically, rather than trying to interpret the instance subidentifiers as string or OID values:

    $ snmpgetnext -c public -v 1 localhost vacmSecurityModel
    SNMP-VIEW-BASED-ACM-MIB::vacmSecurityModel.0."wes" = xxx
    $ snmpgetnext -c public -v 1 -Ob localhost vacmSecurityModel
    SNMP-VIEW-BASED-ACM-MIB::vacmSecurityModel.0.3.119.101.115 = xxx

-Oe

Removes the symbolic labels from enumeration values:

    $ snmpget -c public -v 1 localhost ipForwarding.0
    IP-MIB::ipForwarding.0 = INTEGER: forwarding(1)
    $ snmpget -c public -v 1 -Oe localhost ipForwarding.0
    IP-MIB::ipForwarding.0 = INTEGER: 1

-OE

Modifies index strings to escape the quote characters:

    $ snmpgetnext -c public -v 1 localhost vacmSecurityModel
    SNMP-VIEW-BASED-ACM-MIB::vacmSecurityModel.0."wes" = xxx
    $ snmpgetnext -c public -v 1 -OE localhost vacmSecurityModel
    SNMP-VIEW-BASED-ACM-MIB::vacmSecurityModel.0.\"wes\" = xxx

This allows the output to be reused in shell commands.

-Of

Include the full list of MIB objects when displaying an OID:

.iso.org.dod.internet.mgmt.mib-2.system.sysUpTime.0 =

Timeticks: (14096763) 1 day, 15:09:27.63

-On

Displays the OID numerically:

.1.3.6.1.2.1.1.3.0 = Timeticks: (14096763) 1 day, 15:09:27.63

-Oq

Removes the equal sign and type information when displaying varbind values:

SNMPv2-MIB::sysUpTime.0 1:15:09:27.63

-OQ

Removes the type information when displaying varbind values:

SNMPv2-MIB::sysUpTime.0 = 1:15:09:27.63

-Os

Display the MIB object name (plus any instance or other subidentifiers):

sysUpTime.0 = Timeticks: (14096763) 1 day, 15:09:27.63

-OS

Display the name of the MIB, as well as the object name:

SNMPv2-MIB::sysUpTime.0 = Timeticks: (14096763) 1 day, 15:09:27.63

This is the default OID output format.

-Ot

Display TimeTicks values as raw numbers:

SNMPv2-MIB::sysUpTime.0 = 14096763

-OT

If values are printed as Hex strings, display a printable version as well.

-Ou

Display the OID in the traditional UCD-style (inherited from the original CMU code). That means removing a series of "standard" prefixes from the OID, and displaying the remaining list of MIB object names (plus any other subidentifiers):

system.sysUpTime.0 = Timeticks: (14096763) 1 day, 15:09:27.63

-OU

Do not print the UNITS suffix at the end of the value.

-Ov

Display the varbind value only, not the OID:

    $ snmpget -c public -v 1 -Oe localhost ipForwarding.0
    INTEGER: forwarding(1)

-Ox

Display string values as Hex strings (unless there is a DISPLAY-HINT defined for the corresponding MIB object). By default, the library attempts to determine whether the value is a printable or binary string, and displays it accordingly.

This option does not affect objects that do have a Display Hint.

-OX

Display table indexes in a more "program like" output, imitating a traditional array-style index format:

    $ snmpgetnext -c public -v 1 localhost ipv6RouteTable
    IPv6-MIB::ipv6RouteIfIndex.63.254.1.0.255.0.0.0.0.0.0.0.0.0.0.0.64.1 = INTEGER: 2
    $ snmpgetnext -c public -v 1 -OE localhost ipv6RouteTable
    IPv6-MIB::ipv6RouteIfIndex[3ffe:100:ff00:0:0:0:0:0][64][1] = INTEGER: 2

Most of these options can also be configured via configuration tokens. See the snmp.conf(5) manual page for details.

The mechanism and destination to use for logging of warning and error messages can be controlled by passing various parameters to the -L flag.

-Le

Log messages to the standard error stream.

-Lf FILE

Log messages to the specified file.

-Lo

Log messages to the standard output stream.

-Ls FACILITY

Log messages via syslog, using the specified facility (’d’ for LOG_DAEMON, ’u’ for LOG_USER, or ’0’-’7’ for LOG_LOCAL0 through LOG_LOCAL7).

There are also "upper case" versions of each of these options, which allow the corresponding logging mechanism to be restricted to certain priorities of message. Using standard error logging as an example:

-LE pri

will log messages of priority ’pri’ and above to standard error.

-LE p1-p2

will log messages with priority between ’p1’ and ’p2’ (inclusive) to standard error.

For -LF and -LS the priority specification comes before the file or facility token. The priorities recognised are:

0 or ! for LOG_EMERG,
1 or a for LOG_ALERT,
2 or c for LOG_CRIT,
3 or e for LOG_ERR,
4 or w for LOG_WARNING,
5 or n for LOG_NOTICE,
6 or i for LOG_INFO, and
7 or d for LOG_DEBUG.

Normal output is (or will be!) logged at a priority level of LOG_NOTICE

The interpretation of input object names and the values to be assigned can be controlled using various parameters of the -I flag. The default behaviour will be described at the end of this section.

-Ib

specifies that the given name should be regarded as a regular expression, to match (case-insensitively) against object names in the MIB tree. The "best" match will be used - calculated as the one that matches the closest to the beginning of the node name and the highest in the tree. For example, the MIB object vacmSecurityModel could be matched by the expression vacmsecuritymodel (full name, but different case), or vacm.*model (regexp pattern).

Note that ’.’ is a special character in regular expression patterns, so the expression cannot specify instance subidentifiers or more than one object name. A "best match" expression will only be applied against single MIB object names. For example, the expression sys*ontact.0 would not match the instance sysContact.0 (although sys*ontact would match sysContact). Similarly, specifying a MIB module name will not succeed (so SNMPv2-MIB::sys.*ontact would not match either).

-Ih

disables the use of DISPLAY-HINT information when assigning values. This would then require providing the raw value:

snmpset ... HOST-RESOURCES-MIB::hrSystemDate.0
x "07 D2 0C 0A 02 04 06 08"
instead of a formatted version:
snmpset ... HOST-RESOURCES-MIB::hrSystemDate.0
= 2002-12-10,2:4:6.8

-Ir

disables checking table indexes and the value to be assigned against the relevant MIB definitions. This will (hopefully) result in the remote agent reporting an invalid request, rather than checking (and rejecting) this before it is sent to the remote agent.

Local checks are more efficient (and the diagnostics provided also tend to be more precise), but disabling this behaviour is particularly useful when testing the remote agent.

-IR

enables "random access" lookup of MIB names. Rather than providing a full OID path to the desired MIB object (or qualifying this object with an explicit MIB module name), the MIB tree will be searched for the matching object name. Thus .iso.org.dod.internet.mib-2.system.sysDescr.0 (or SNMPv2-MIB::sysDescr.0) can be specified simply as sysDescr.0.

Warning:

Since MIB object names are not globally unique, this approach may return a different MIB object depending on which MIB files have been loaded.

The MIB-MODULE::objectName syntax has the advantage of uniquely identifying a particular MIB object, as well as being slightly more efficient (and automatically loading the necessary MIB file if necessary).

-Is SUFFIX

adds the specified suffix to each textual OID given on the command line. This can be used to retrieve multiple objects from the same row of a table, by specifying a common index value.

-IS PREFIX

adds the specified prefix to each textual OID given on the command line. This can be used to specify an explicit MIB module name for all objects being retrieved (or for incurably lazy typists).

-Iu

enables the traditional UCD-style approach to interpreting input OIDs. This assumes that OIDs are rooted at the ’mib-2’ point in the tree (unless they start with an explicit ’.’ or include a MIB module name). So the sysDescr instance above would be referenced as system.sysDescr.0.

Object names specified with a leading ’.’ are always interpreted as "fully qualified" OIDs, listing the sequence of MIB objects from the root of the MIB tree. Such objects and those qualified by an explicit MIB module name are unaffected by the -Ib, -IR and -Iu flags.

Otherwise, if none of the above input options are specified, the default behaviour for a "relative" OID is to try and interpret it as an (implicitly) fully qualified OID, then apply "random access" lookup (-IR), followed by "best match" pattern matching (-Ib).

PREFIX

The standard prefix for object identifiers (when using UCD-style output). Defaults to .iso.org.dod.internet.mgmt.mib-2

MIBS

The list of MIBs to load. Defaults to SNMPv2-TC:SNMPv2-MIB:IF-MIB:IP-MIB:TCP-MIB:UDP-MIB:SNMP-VACM-MIB. Overridden by the -m option.

MIBDIRS

The list of directories to search for MIBs. Defaults to /usr/share/snmp/mibs. Overridden by the -M option.

/etc/snmp/snmpd.conf

Agent configuration file. See snmpd.conf(5).

/etc/snmp/snmp.conf

~/.snmp/snmp.conf

Application configuration files. See snmp.conf(5).

snmpget(1), snmpgetnext(1), snmpset(1), snmpbulkget(1), snmpbulkwalk(1), snmpwalk(1), snmptable(1), snmpnetstat(1), snmpdelta(1), snmptrap(1), snmpinform(1), snmpusm(1), snmpstatus(1), snmptest(1), snmp.conf(5).