NAME
snmpcmd - options and behaviour common to most of the
Net-SNMP command-line tools
SYNOPSIS
snmpcmd [OPTIONS] AGENT [PARAMETERS]
DESCRIPTION
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.
OPTIONS
- -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 its usage of keying information,
see the Net-SNMP tutorial web site ( http://www.Net-SNMP.org/tutorial-5/commands/
). Overrides the defAuthMasterKey (-3m), defPrivMasterKey (-3M),
defAuthLocalizedKey (-3k) or defPrivLocalizedKey (-3K) tokens,
respectively, in the snmp.conf file, see
- -a authProtocol
- Set the authentication protocol (MD5 or 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
- -c community
- Set the community string for SNMPv1/v2c transactions. Overrides
the defCommunity token in the snmp.conf file.
- -d
- Dump (in hexadecimal) the raw SNMP packets sent and received.
- -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 (or augments) the
environment variable MIBS, the snmp.conf directive
mibs, and the list of MIBs hardcoded into the Net-SNMP
library.
- If MIBLIST has a leading '-' or '+' character, then the
MIB modules listed are loaded in addition to the default list,
coming before or after this list respectively. Otherwise, the
specified MIBs are loaded instead of this default list.
- The special keyword ALL is used to load all MIB modules
in the MIB directory search list. Every file whose name does not
begin with "." will be parsed as if it were a MIB file.
- -M DIRLIST
- Specifies a colon separated list of directories to search for
MIBs. This overrides (or augments) the environment variable
MIBDIRS, the snmp.conf directive mibdirs, and the
default directory hardcoded into the Net-SNMP library
(/usr/share/snmp/mibs).
- If DIRLIST has a leading '-' or '+' character, then the
given directories are added to the default list, being searched
before or after the directories on this list respectively.
Otherwise, the specified directories are searched instead of
this default list.
Note that the directories appearing later in the list have have
precedence over earlier ones. To avoid searching any MIB
directories, set the MIBDIRS environment variable to the empty
string ("").
Note that MIBs specified using the -m option or the mibs
configuration directive will be loaded from one of the directories
listed by the -M option (or equivalents). The mibfile
directive takes a full path to the specified MIB file, so this does
not need to be in the MIB directory search list.
- -n contextName
- Set the 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. 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 or AES) used for encrypted SNMPv3
messages. Overrides the defPrivType token in the
snmp.conf file. This option is only valid if the Net-SNMP
software was build to use OpenSSL.
- -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
- -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.
- --name=value
- Allows to specify any token ("name") supported in the
snmp.conf file and sets its value to "value". Overrides the
corresponding token in the snmp.conf file. See
for the full list of tokens.
AGENT SPECIFICATION
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.
MIB PARSING OPTIONS
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
- Allow ASN.1 comments to 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. This
behaviour can also be set with the configuration token
strictCommentTerm.
- -Pd
- Disables saving the DESCRIPTION of MIB objects when parsing MIB
files, reducing the amount of memory used by the running
application.
- -Pe
- 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. This 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
- 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. This 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
OUTPUT OPTIONS
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
manual page for details.
LOGGING OPTIONS
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
INPUT OPTIONS
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::hrSystemData.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).
ENVIRONMENT VARIABLES
- 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.
FILES
- /etc/snmp/snmpd.conf
- Agent configuration file. See .
- /etc/snmp/snmp.conf
- ~/.snmp/snmp.conf
- Application configuration files. See
SEE ALSO
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).