snmpcmd - options and behaviour common to most of the Net-SNMP command-line tools

snmpcmd [OPTIONS] AGENT [PARAMETERS]

This manual page describes the common options for the SNMP commands: snmpbulkget, snmpbulkwalk, snmpdelta, snmpget, snmpgetnext, snmpnetstat, snmpset, snmpstatus, snmptable, snmptest, snmptrap", snmpdf, snmpusm , snmpwalk ." The command line applications use the SNMP protocol to communicate with an SNMP capable network entity, an agent. Individual applications typically (but not necessarily) take additional parameters that are given after the agent specification. These parameters are documented in the manual pages for each application.

-3[MmKk] 0xHEXKEY

Sets the keys to be used for SNMPv3 transactions. These options allow you to set the master authentication and encryption keys (-3m and -3M respectively) or set the localized authentication and encryption keys (-3k and -3K respectively). SNMPv3 keys can be either passed in by hand using these flags, or by the use of keys generated from passwords using the -A and -X flags discussed below. For further details on SNMPv3 and it's usage of keying information, see the Net-SNMP tutorial web site ( http://www.Net-SNMP.org/tutorial-5/commands/ ). See the snmp.conf manual page on the defAuthMasterKey and related tokens for more information as well.

-a authProtocol

Set the authentication protocol (MD5|SHA) used for authenticated SNMPv3 messages. Overrides the defAuthType token in the snmp.conf file.

-A authPassword

Set the authentication pass phrase used for authenticated SNMPv3 messages. Overrides the defAuthPassphrase token in the snmp.conf file. It is insecure to specify pass phrases on the command line, see snmp.conf(5).

-c community

Set the community string for SNMPv1/v2c transactions. Overrides the defcommunity token in the snmp.conf file.

-d

Dump (in hexadecimal) the sent and received SNMP packets.

-D TOKEN[,...] Turn on debugging output for the given TOKEN(s). Try ALL for extremely verbose output.

-e engineID

Set the authoritative (security) engineID used for SNMPv3 REQUEST messages. It is typically not necessary to specify this, as it will usually be discovered automatically.

-E engineID

Set the context engineID used for SNMPv3 REQUEST messages scopedPdu. If not specified, this will default to the authoritative engineID.

-h, --help

Display a brief usage message and then exit.

-H

Display a list of configuration file directives understood by the command and then exit.

-I [brRhu]

Specifies input parsing options. See INPUT OPTIONS below.

-l secLevel

Set the securityLevel used for SNMPv3 messages (noAuthNoPriv|authNoPriv|authPriv). Appropriate pass phrase(s) must provided when using any level higher than noAuthNoPriv. Overrides the defSecurityLevel token in the snmp.conf file.

-L [eEfFoOsS]

Specifies output logging options. See LOGGING OPTIONS below.

-m MIBLIST

Specifies a colon separated list of MIB modules (not files) to load for this application. This overrides the environment variable MIBS.

The special keyword ALL is used to specify all modules in all directories when searching for MIB files. Every file whose name does not begin with "." will be parsed as if it were a MIB file.

If the MIBLIST has a leading '+', then the listed MIB modules are loaded in addition to MIB modules specified in the environment variable MIBS.

If a mibfile token is specified in the snmp.conf file, the -m MIB option overrides the mibfile token.

-M DIRLIST

Specifies a colon separated list of directories to search for MIBs. This overrides the environment variable MIBDIRS.

If DIRLIST has a leading '+', then the given directories are added to the list of MIB directories. Without the leading '+', the given directory list overrides the list specified with the environment variable MIBDIRS. Note that the directories listed at the end of the list have precedence over directories at the beginning of the list.

If no value is specified for the environment variable MIBDIRS, then the command will still search a default mib directory, after it searches the MIB directories specified on the -M option. The default directory is /usr/share/snmp/mibs. To avoid having a default mib directory searched, set the MIBDIRS environment variable to "". Even if the default MIB directory is searched, the directories specified in the -M option have precedence in the search order over the default directory.

If the -M option is specified and either a mibfile or mibdirs token is also specified in the snmp.conf file, the directories in the -M option have precedence in the MIB search order, over the directories set with both the mibdirs token and the mibfile token.

-n contextName

Set the destination contextName used for SNMPv3 messages. The default contextName is the empty string "". Overrides the defContext token in the snmp.conf file.

-O [abeEfnqQsStTuUvxX]

Specifies output printing options. See OUTPUT OPTIONS below.

-P [cdeRuwW]

Specifies MIB parsing options. See MIB PARSING OPTIONS below.

-r retries

Specifies the number of retries to be used in the requests. The default is 5.

-t timeout

Specifies the timeout in seconds between retries. The default is 1.

-u secName

Set the securityName used for authenticated SNMPv3 messages. Overrides the defSecurityName token in the snmp.conf file.

-v 1 | 2c | 3 Specifies the protocol version to use: 1 (RFCs 1155-1157), 2c (RFCs 1901-1908), or 3 (RFCs 2571-2574). The default is typically version 3. This option overrides the defVersion token in the snmp.conf file.

-V, --version

Display version information for the application and then exit.

-x privProtocol

Set the privacy protocol (DES) used for encrypted SNMPv3 messages.

-X privPassword

Set the privacy pass phrase used for encrypted SNMPv3 messages. Overrides the defPrivPassphrase token in the snmp.conf file. It is insecure to specify pass phrases on the command line, see snmp.conf(5).

-Z boots,time

Set the engineBoots and engineTime used for authenticated SNMPv3 messages. This will initialize the local notion of the agents boots/time with an authenticated value stored in the LCD. It is typically not necessary to specify this option, as these values will usually be discovered automatically.

The string AGENT in the SYNOPSIS above specifies the remote SNMP entity with which to communicate. This specification takes the form:

[<transport-specifier>:]<transport-address>

At its simplest, the AGENT specification may consist of a hostname, or an IPv4 address in the standard "dotted quad" notation. In this case, communication will be attempted using UDP/IPv4 to port 161 of the given host. Otherwise, the <transport-address> part of the specification is parsed according to the following table:

<transport-specifier>

<transport-address> format

udp

hostname[:port] or IPv4-address[:port]

tcp

hostname[:port] or IPv4-address[:port]

unix

pathname

ipx

[network]:node[/port]

aal5pvc or pvc

[interface.][VPI.]VCI

udp6 or udpv6 or udpipv6

hostname[:port] or IPv6-address:port or '['IPv6-address']'[:port]

tcp6 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 '/'.

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.

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.

-Pw

Show some warning messages in resolving the MIB files. Can be also set with the configuration token "mibWarningLevel".

-PW

Show additional warning messages. Can be also set with the configuration token "mibWarningLevel".

-Pe

Show MIB errors. Can be also set with the configuration token "showMibErrors". An example of an error that would be shown is if an imported module is not found during MIB parsing.

-Pc

Allow ASN.1 comment to extend to the end of the MIB source line (i.e. disallow the use of "--" to terminate comments). This overcomes some problems with manually maintained MIB files. Can be also set with the configuration token "strictCommentTerm".

-Pd

Toggles the default of whether or not to save the DESCRIPTIONs of the MIB objects when parsing. Since the default is to save the DESCRIPTIONS, specifying -Pd will cause the DESCRIPTIONs not to be saved during MIB parsing. For example:

snmptranslate -Td -OS -IR system.sysDescr.0

will show a description, while

snmptranslate -Td -OS -IR -Pd system.sysDescr.0

will not show a description. Collecting the DESCRIPTION information into the parsed hierarchy increases the memory used by the size of each DESCRIPTION clause.

-Pu

Allow underline characters in symbols. Can be also set with the configuration token "mibAllowUnderline".

-PR

Replace MIB objects using the last read MIB file. The parser will replace MIB objects in its hierarchy whenever it sees a sub-identifier and name match. WARNING: Setting this option may result in an incorrect hierarchy. Can be also set with the configuration token "mibReplaceWithLatest".

Output display can be controlled by passing various parameters to the -O flag. The following examples should demonstrate this.

The default output looks as follows:

snmpget -c public -v 1 localhost system.sysUpTime.0

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

-Oq

Removes the equal sign and type information:

system.sysUpTime.0 1:15:09:27.63

-OQ

Removes the type information:

system.sysUpTime.0 = 1:15:09:27.63

-Of

Gives you the complete OID:

.iso.org.dod.internet.mgmt.mib-2.system.sysUpTime.0 = Timeticks: (14096763) 1 day, 15:09:27.63

-Os

Deletes all but the last symbolic part of the OID:

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

-OS

A variation on -Os that adds the name of the MIB that defined the object:

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

(from release 5.0, this is now the default output format)

-Ou

Prints the OID in the UCD-style (inherited from the original CMU code), That means removing a series of "standard" prefixes, if relevant, and breaking down the OID into the displayable pieces. For example, the OID vacmSecruityModel.0.3.119.101.115 is broken down by default and the string hidden in the OID is shown. The result would look like: vacmSecurityModel.0."test". The -Ob option disables this feature.

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

-On

Prints the OID numerically:

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

-Oe

Removes the symbolic labels from enumerations:

snmpget -c public -v 1 localhost ip.ipForwarding.0

ip.ipForwarding.0 = INTEGER: forwarding(1)

snmpget -c public -v 1 -Oe localhost ip.ipForwarding.0

ip.ipForwarding.0 = INTEGER: 1

-Ob

When OIDs contain a index to a table, they are broken into the displayable pieces and shown to you. For example the OID vacmSecurityModel.0.3.119.101.115 is nicely broken down by default and the string hidden in the OID is shown to you as vacmSecurityModel.0."wes". The -Ob option disables this feature and displays it as vacmSecurityModel.0.3.119.101.115 again.

-OE

This modifies the index strings to include a \ to escape the quotes, to allow them to be reused in shell commands, such as vacmSecurityModel.0.\"wes\"

-OX

This modifies the output of index OIDs, to look more "program like". Square brackets are placed around each index, and the DISPLAY-HINT information and string conversions are used to format each index. If you take an entry from the IPV6-MIB::ipv6RouteTable, it is indexed with an IPv6 address and two integers, and if you are used to IPv6 addresses you will know that decimal OIDs are not the preferred notation. Compare:

snmpgetnext -OS host IPV6-MIB: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 -OSX host IPV6-MIB:ipv6RouteTable

IPV6-MIB::ipv6RouteIfIndex[3ffe:100:ff00:0:0:0:0:0][64][1] = INTEGER: 2

-Oa

If a string-valued object definition does not include a Display Hint, then the library attempts to determine whether it is an ascii or binary string, and displays the value accordingly. This flag bypasses this check, and displays all strings as ASCII. Note that this does not affect objects that do have a Display Hint.

-Ox

This works similarly to '-Oa', but displays strings as Hex.

-OT

If hexadecimal code is printed, this will also print any printable characters after the hexadecimal codes.

-Ov

Output only the variable value, not the OID:

snmpget -c public -v 1 -Ov localhost ip.ipForwarding.0

INTEGER: forwarding(1)

-OU

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

-Ot

Output timeticks values as raw numbers:

system.sysUpTime.0 = 14096763

Note that most of these options can be turned on or off by default by tuning the snmp.conf file. 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 -I flag specifies various options that control how your input to the program is parsed. By default, all input parsing methods are used: First the OID is parsed regularly, then -IR is used, then -Ib is used, unless one of the following flags is specified which will force it to only use one method.

-IR

The -IR flag specifies random access lookup, so that if the entire OID path is not specified, it will search for a node in the MIB tree with the given name. Normally, you would have to specify the vacmSecurityModel OID above as .iso.org.dod.internet.snmpV2.snmpModules.snmpVacmMIB.vacmMIBObjects.vacmSecurityToGroupTable.vacmSecurityToGroupEntry.vacmSecurityModel.0."wes", but the use of the -IR flag allows you to shorten that to just vacmSecurityModel.0."wes". (Though this OID really needs to be quoted - 'vacmSecurityModel.0."wes"' - to prevent the shell from swallowing the double quotes).

Additionally, see the RANDOM ACCESS MIBS section below.

-Ib

The -Ib flag indicates that the expression you gave it is actually a regular expression that should be used to search for the best match possible in the MIB tree. This would allow you to specify the node vacmSecurityModel MIB node as something as generic as vacmsecuritymodel (since case insensitive searches are done) or vacm.*model. Note that multiple matches are obviously possible (.* matches everything), and the best result is currently calculated as the one that matches the closest to the beginning of the node name and the highest in the tree. A current side effect of this option is that you cannot specify indexes or multiple nodes, since the '.' is treated as part of the regular expression.

-Iu

Use the traditional UCD-style input approach of assuming that OIDs are rooted at the 'mib-2' point in the tree (unless they start with an explicit '.') If random access lookup is in effect (which is the default for most commands), then this will only affect OIDs specified with a leading numberic subidentifier (and no initial '.') Thus an input of "snmpcmd ... 1" would refer to 'iso' (from v5.0 onwards) while "snmpcmd -Iu ... 1" would refer to 'system'.

-Ir

By default, indices into tables and values to be assigned to objects are checked against range and type specified in the MIB. The -Ir flag disables this check. This flag is mostly useful when you are testing an agent. For normal operation it is useful to get your requests checked before they are sent to the remote agent (the diagnostic that the library can provide is also much more precise).

-Ih

By default, the library will use DISPLAY-HINT information when assigning values. This flag disables this behaviour. The result is that instead of

snmpset localhost HOST-RESOURCES-MIB::hrSystemDate.0 = 2002-12-10,2:4:6.8

you will have to write

snmpset localhost HOST-RESOURCES-MIB::hrSystemData.0 x "07 D2 0C 0A 02 04 06 08"

-Is SUFFIX

Add the specified suffix to each textual OID given on the command line. It is useful to specify a common index value when you want to retrieve multiple objects from the same row of a table.

-IS PREFIX

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

In previous releases of the UCD-SNMP package (and if using the -Iu option), an object identifier such as system.sysDescr.0 will be lookup in a single "well known" place, built into the SNMP library (or specified by the PREFIX environment variable). The standard place is: .iso.org.dod.internet.mgmt.mib-2. The identifier may alternatively be a complete object identifier, this is designated by a leading "dot" if using UCD-input style, and is the first thing tried otherwise. To simplify the specification of object identifiers the library supports random access to the identifiers in the MIBs. This is requested by the -IR option to the SNMP applications. Additionally, -Os prints OIDs in this manner. Using this, system.sysDescr.0 may also be entered as sysDescr.0. To search only a single MIB for the identifier (if it appears in more than one), specify it as SNMPv2-MIB::sysDescr.0. (use -OS to print output OIDs in this manner, though this is the default as from v5.0). This notation will also ensure that the specified MIB is loaded, i.e. it need not be mentioned in the -m option (or MIBS environment variable).

PREFIX

The standard prefix for object identifiers (if 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).