snmp.conf

SNMP.CONF(5) Net-SNMP SNMP.CONF(5)

NAME

   snmp.conf - configuration files for the Net-SNMP applications

DESCRIPTION

   Applications  built  using  the  Net-SNMP  libraries  typically use one or more configuration files to control various aspects of their operation.  These files (snmp.conf and snmp.lo
   cal.conf) can be located in one of several locations, as described in the snmp_config(5) manual page.

   In particular, /etc/snmp/snmp.conf is a common file, containing the settings shared by all users of the system.  ~/.snmp/snmp.conf is a personal file, with the settings specific to  a
   particular user.

HOST-SPECIFIC FILES

   Host-specific  files  may  also  be loaded and will be searched for if a transport name is specified that matches a PATH/hosts/HOST.conf file.  For example, if you wanted a particular
   host to use SNMPv2c by default you could create a ~/.snmp/hosts/NAME.conf file and in it put:

          defVersion 2c

   Any connections set to connect to the hostname NAME will use SNMPv2c.  Also see the transport token below for additional host-specific examples.

   Host-specific configuration files are loaded at the time the connection is opened.  Thus they're generally loaded after all other configuration files and can be used to override  set
   tings from the generic files.

   To avoid loading any host-specific config files set "dontLoadHostConfig true" in your snmp.conf file.

COMMAND-LINE OPTIONS

   All of the tokens described in this file can be used on the command line of Net-SNMP applications as well by prefixing them with "--".  EG, specifying --dontLoadHostConfig=true on the
   command line will turn of loading of the host specific configuration files.

IMPORTANT NOTE

   Several of these directives may contain sensitive information (such as pass phrases).  Configuration files that include such settings should only be readable by the user concerned.

   As  well  as  application-specific configuration tokens, there are several directives that relate to standard library behaviour, relevant to most Net-SNMP applications.  Many of these
   correspond to standard command-line options, which are described in the snmpcmd(1) manual page.

   These directives can be divided into several distinct groups.

CLIENT BEHAVIOUR

   defDomain application domain
          The transport domain that should be used for a certain application type unless something else is specified.

   defTarget application domain target
          The target that should be used for connections to a certain application if the connection should be in a specific domain.

   defaultPort PORT
          defines the default UDP port that client SNMP applications will attempt to connect to.  This can be overridden by explicitly including a port number in the AGENT specification.
          See the snmpcmd(1) manual page for more details.

          If not specified, the default value for this token is 161.

   transport HOSTSPECIFIER
          This special token should go into a hostname-specific configuration file in a hosts sub-directory.  For example if the file hosts/foo.conf exists in the search path it will  be
          loaded  if a transport name of foo was used.  Within the foo.conf file you may put both general snmp.conf settings as well as a special transport string to specify the destina
          tion to connect to.  For example, putting:

                 transport tcp:foo.example.com:9876

          in the hosts/foo.conf file will make applications referencing the foo hostname (e.g. snmpget) to actually connect via TCP to foo.exmaple.com on port 9876.

   defVersion (1|2c|3)
          defines the default version of SNMP to use.  This can be overridden using the -v option.

   defCommunity STRING
          defines the default community to use for SNMPv1 and SNMPv2c requests.  This can be overridden using the -c option.

   alias NAME DEFINITION
          Creates an aliased tied to NAME for a given transport definition.  The alias can the be referred to using an alias: prefix.  Eg, a line of "alias here udp:127.0.0.1:6161" would
          allow you to use a destination host of "alias:here" instead of "udp:127.0.0.1:6161".  This becomes more useful with complex transport addresses involving IPv6 addresses, etc.

   dumpPacket yes
          defines whether to display a hexadecimal dump of the raw SNMP requests sent and received by the application.  This is equivalent to the -d option.

   doDebugging (1|0)
          turns on debugging for all applications run if set to 1.

   debugTokens TOKEN[,TOKEN...]
          defines the debugging tokens that should be turned on when doDebugging is set.  This is equivalent to the -D option.

   debugLogLevel (emerg|alert|crit|err|warning|notice|info|debug)
          Set the priority level for logging of debug output. Defaults to debug.

   16bitIDs yes
          restricts requestIDs, etc to 16-bit values.

          The SNMP specifications define these ID fields as 32-bit quantities, and the Net-SNMP library typically initialises them to random values for security.  However  certain  (bro
          ken) agents cannot handle ID values greater than 2^16 - this option allows interoperability with such agents.

   clientaddr [<transport-specifier>:]<transport-address>
          specifies the source address to be used by command-line applications when sending SNMP requests. See snmpcmd(1) for more information about the format of addresses.

          This value is also used by snmpd when generating notifications.

   clientaddrUsesPort no
          specifies,  if  clientaddr  option contains a port number. Set this option to "yes", if clientaddr contains a port number and this port should be used for sending outgoing SNMP
          requests. This option only affects IPv4 client addresses and is ignored for IPv6 client addresses.

   clientRecvBuf INTEGER
          specifies the desired size of the buffer to be used when receiving responses to SNMP requests.  If the OS hard limit is lower than the clientRecvBuf value, then  this  will  be
          used instead.  Some platforms may decide to increase the size of the buffer actually used for internal housekeeping.

          This directive will be ignored if the platforms does not support setsockopt().

   clientSendBuf INTEGER
          is similar to clientRecvBuf, but applies to the size of the buffer used when sending SNMP requests.

   noRangeCheck yes
          disables the validation of varbind values against the MIB definition for the relevant OID.  This is equivalent to the -Ir option.

          This directive is primarily relevant to the snmpset command, but will also apply to any application that calls snmp_add_var() with a non-NULL value.

   noTokenWarnings
          disables warnings about unknown config file tokens.

   reverseEncodeBER (1|yes|true|0|no|false)
          controls how the encoding of SNMP requests is handled.

          The  default behaviour is to encode packets starting from the end of the PDU and working backwards.  This directive can be used to disable this behaviour, and build the encoded
          request in the (more obvious) forward direction.

          It should not normally be necessary to change this setting, as the encoding is basically the same in either case - but working backwards typically produces a slightly more  ef
          ficient encoding, and hence a smaller network datagram.

   dontLoadHostConfig (1|yes|true|0|no|false)
          Specifies whether or not the host-specific configuration files are loaded.  Set to "true" to turn off the loading of the host specific configuration files.

   retries INTEGER
          Specifies the number of retries to be used in the requests.

   timeout INTEGER
          Specifies the timeout in seconds between retries.

SNMPv1/SNMPv2c SETTINGS

   disableSNMPv1  (1|yes|true|0|no|false)

   disableSNMPv2c (1|yes|true|0|no|false)
          Disables protocol versions at runtime. Incoming and outgoing packets for the protocol will be dropped.

SNMPv3 SETTINGS

   disableSNMPv3  (1|yes|true|0|no|false)
          Disables protocol versions at runtime. Incoming and outgoing packets for the protocol will be dropped.

   defSecurityName STRING
          defines the default security name to use for SNMPv3 requests.  This can be overridden using the -u option.

   defSecurityLevel noAuthNoPriv|authNoPriv|authPriv
          defines the default security level to use for SNMPv3 requests.  This can be overridden using the -l option.

          If not specified, the default value for this token is noAuthNoPriv.

          Note:  authPriv is only available if the software has been compiled to use the OpenSSL libraries.

   defPassphrase STRING

   defAuthPassphrase STRING

   defPrivPassphrase STRING
          define the default authentication and privacy pass phrases to use for SNMPv3 requests.  These can be overridden using the -A and -X options respectively.

          The defPassphrase value will be used for the authentication and/or privacy pass phrases if either of the other directives are not specified.

   defAuthType MD5|SHA|SHA-512|SHA-384|SHA-256|SHA-224

   defPrivType DES|AES
          define the default authentication and privacy protocols to use for SNMPv3 requests.  These can be overridden using the -a and -x options respectively.

          If not specified, SNMPv3 requests will default to MD5 authentication and DES encryption.

          Note:  If  the  software  has  not been compiled to use the OpenSSL libraries, then only MD5 authentication is supported.  Neither SHA authentication nor any form of encryption
                 will be available.

   defContext STRING
          defines the default context to use for SNMPv3 requests.  This can be overridden using the -n option.

          If not specified, the default value for this token is the default context (i.e. the empty string "").

   defSecurityModel STRING
          defines the security model to use for SNMPv3 requests.  The default value is "usm" which is the only widely used security model for SNMPv3.

   defAuthMasterKey 0xHEXSTRING

   defPrivMasterKey 0xHEXSTRING

   defAuthLocalizedKey 0xHEXSTRING

   defPrivLocalizedKey 0xHEXSTRING
          define the (hexadecimal) keys to be used for SNMPv3 secure communications.  SNMPv3 keys are frequently derived from a passphrase, as  discussed  in  the  defPassphrase  section
          above.  However  for  improved  security  a  truely random key can be generated and used instead (which would normally has better entropy than a password unless it is amazingly
          long).  The directives are equivalent to the short-form command line options -3m, -3M, -3k, and -3K.

          Localized keys are master keys which have been converted to a unique key which is only suitable for on particular SNMP engine (agent).  The length of the key needs to be appro
          priate for the authentication or encryption type being used (auth keys: MD5=16 bytes, SHA1=20 bytes; priv keys: DES=16 bytes (8 bytes of which is used as an IV and not a  key),
          and AES=16 bytes).

   sshtosnmpsocket PATH
          Sets the path of the sshtosnmp socket created by an application (e.g. snmpd) listening for incoming ssh connections through the sshtosnmp unix socket.

   sshtosnmpsocketperms MODE [OWNER [GROUP]]
          Sets  the  mode,  owner  and group of the sshtosnmp socket created by an application (e.g. snmpd) listening for incoming ssh connections through the sshtosnmp unix socket.  The
          socket needs to be read/write privileged for SSH users that are allowed to connect to the SNMP service (VACM access still needs to be granted as well, most likely  through  the
          TSM security model).

   sshusername NAME
          Sets the SSH user name for logging into the remote system.

   sshpubkey FILE
          Set the public key file to use when connecting to a remote system.

   sshprivkey FILE
          Set the private key file to use when connecting to a remote system.

SERVER BEHAVIOUR

   persistentDir DIRECTORY
          defines the directory where snmpd and snmptrapd store persistent configuration settings.

          If not specified, the persistent directory defaults to /var/lib/snmp

   noPersistentLoad yes

   noPersistentSave yes
          disable the loading and saving of persistent configuration information.

          Note:  This will break SNMPv3 operations (and other behaviour that relies on changes persisting across application restart).  Use With Care.

   tempFilePattern PATTERN
          defines a filename template for creating temporary files, for handling input to and output from external shell commands.  Used by the mkstemp() and mktemp() functions.

          If not specified, the default pattern is "/tmp/snmpdXXXXXX".

   serverRecvBuf INTEGER
          specifies  the  desired size of the buffer to be used when receiving incoming SNMP requests.  If the OS hard limit is lower than the serverRecvBuf value, then this will be used
          instead.  Some platforms may decide to increase the size of the buffer actually used for internal housekeeping.

          This directive will be ignored if the platforms does not support setsockopt().

   serverSendBuf INTEGER
          is similar to serverRecvBuf, but applies to the size of the buffer used when sending SNMP responses.

   sourceFilterType none|acceptlist|blocklist
          specifies whether or not addresses added with sourceFilterAddress are accepted or blocked. The default is none, indicating that incoming packets will not be checked agains  the
          filter list.

   sourceFilterAddress ADDRESS
          specifies an address to be added to the source address filter list.  sourceFilterType configuration determines whether or not addresses are accepted or blocked.

MIB HANDLING

   mibdirs DIRLIST
          specifies  a  list of directories to search for MIB files.  This operates in the same way as the -M option - see snmpcmd(1) for details.  Note that this value can be overridden
          by the MIBDIRS environment variable, and the -M option.

   mibs MIBLIST
          specifies a list of MIB modules (not files) that should be loaded.  This operates in the same way as the -m option - see snmpcmd(1) for details.  Note that  this  list  can  be
          overridden by the MIBS environment variable, and the -m option.

   mibfile FILE
          specifies  a  (single) MIB file to load, in addition to the list read from the mibs token (or equivalent configuration).  Note that this value can be overridden by the MIBFILES
          environment variable.

   showMibErrors (1|yes|true|0|no|false)
          whether to display MIB parsing errors.

   commentToEOL (1|yes|true|0|no|false)
          whether MIB parsing should be strict about comment termination.  Many MIB writers assume that ASN.1 comments extend to the end of the text line, rather than being terminated by
          the next "--" token.  This token can be used to accept such (strictly incorrect) MIBs.
          Note that this directive was previous (mis-)named strictCommentTerm, but with the reverse behaviour from that implied by the name.  This earlier token  is  still  accepted  for
          backwards compatibility.

   mibAllowUnderline (1|yes|true|0|no|false)
          whether to allow underline characters in MIB object names and enumeration values.  This token can be used to accept such (strictly incorrect) MIBs.

   mibWarningLevel INTEGER
          the minimum warning level of the warnings printed by the MIB parser.

OUTPUT CONFIGURATION

   logTimestamp (1|yes|true|0|no|false)
          Whether  the  commands should log timestamps with their error/message logging or not.  Note that output will not look as pretty with timestamps if the source code that is doing
          the logging does incremental logging of messages that are not line buffered before being passed to the logging routines.  This option is only used when file logging is active.

   printNumericEnums (1|yes|true|0|no|false)
          Equivalent to -Oe.

   printNumericOids (1|yes|true|0|no|false)
          Equivalent to -On.

   dontBreakdownOids (1|yes|true|0|no|false)
          Equivalent to -Ob.

   escapeQuotes (1|yes|true|0|no|false)
          Equivalent to -OE.

   quickPrinting (1|yes|true|0|no|false)
          Equivalent to -Oq.

   printValueOnly (1|yes|true|0|no|false)
          Equivalent to -Ov.

   dontPrintUnits (1|yes|true|0|no|false)
          Equivalent to -OU.

   numericTimeticks (1|yes|true|0|no|false)
          Equivalent to -Ot.

   printHexText (1|yes|true|0|no|false)
          Equivalent to -OT.

   hexOutputLength integer
          Specifies where to break up the output of hexadecimal strings.  Set to 0 to disable line breaks.  Defaults to 16.

   suffixPrinting (0|1|2)
          The value 1 is equivalent to -Os and the value 2 is equivalent to -OS.

   oidOutputFormat (1|2|3|4|5|6)
          Maps -O options as follow: -Os=1, -OS=2, -Of=3, -On=4, -Ou=5.  The value 6 has no matching -O option. It suppresses output.

   extendedIndex (1|yes|true|0|no|false)
          Equivalent to -OX.

   noDisplayHint (1|yes|true|0|no|false)
          Disables the use of DISPLAY-HINT information when parsing indices and values to set. Equivalent to -Ih.

   outputPrecision PRECISION
          Uses the PRECISION string to allow modification of the value output format. See snmpcmd(1) for details.  Equivalent to -Op (which takes precedence over the config file).

FILES

   System-wide configuration files:
          /etc/snmp/snmp.conf
          /etc/snmp/snmp.local.conf

   User-specific configuration settings:
          $HOME/.snmp/snmp.conf
          $HOME/.snmp/snmp.local.conf

   Destination host specific files:
          /etc/snmp/hosts/HOSTNAME.conf
          $HOME/.snmp/hosts/HOSTNAME.conf

SEE ALSO

   snmp_config(5), netsnmp_config_api(3), snmpcmd(1).

V5.9.4.pre2 21 Apr 2010 SNMP.CONF(5)