snmptrapd - Receive and log SNMP trap messages.




   snmptrapd  is  an SNMP application that receives and logs SNMP TRAP and
   INFORM messages.

   Note: the default is to listen on UDP port 162 on all IPv4  interfaces.
   Since  162  is  a  privileged  port, snmptrapd must typically be run as


   -a      Ignore authenticationFailure traps.

   -A      Append to the log file rather than truncating it.

           Note that this needs to come before any  -Lf  options  that  it
           should apply to.

   -c FILE Read FILE as a configuration file (or a comma-separated list of
           configuration files).

   -C      Do not read any configuration files except the  one  optionally
           specified by the -c option.

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

           Turn  on  debugging output for the given TOKEN(s).  Try ALL for
           extremely verbose output.

   -f      Do not fork() from the calling shell.

           When logging to standard output, use the format in  the  string
           FORMAT.   See  the section FORMAT SPECIFICATIONS below for more

   -h, --help
           Display a brief usage message and then exit.

   -H      Display a list of configuration file directives  understood  by
           the trap daemon and then exit.

           Specifies  which  modules should (or should not) be initialized
           when snmptrapd starts up.  If the comma-separated  INITLIST  is
           preceded  with a '-', it is the list of modules that should not
           be started.  Otherwise this is the list  of  the  only  modules
           that should be started.

           To  get  a  list  of  compiled  modules, run snmptrapd with the
           arguments -Dmib_init -H (assuming debugging  support  has  been
           compiled in).

           Specify where logging output should be directed (standard error
           or output, to a file or via syslog).  See  LOGGING  OPTIONS  in
           snmpcmd(1) for details.

           Specifies  a  colon  separated  list of MIB modules to load for
           this application.   This  overrides  the  environment  variable
           MIBS.  See snmpcmd(1) for details.

           Specifies  a  colon separated list of directories to search for
           MIBs.  This overrides the environment  variable  MIBDIRS.   See
           snmpcmd(1) for details.

   -n      Do  not  attempt  to  translate  source  addresses  of incoming
           packets into hostnames.

   -p FILE Save the process ID of the trap daemon in FILE.

   -O [abeEfnqQsStTuUvxX]
           Specifies how MIB objects and other output should be displayed.
           See  the  section  OUTPUT OPTIONS in the snmpcmd(1) manual page
           for details.

   -t      Do not log traps to syslog.  This disables logging  to  syslog.
           This  is  useful  if you want the snmptrapd application to only
           run traphandle hooks and not to log any traps to any location.

   -v, --version
           Print version information for the trap daemon and then exit.

           Connect to the AgentX master agent on  the  specified  address,
           rather than the default "/var/agentx/master".  See snmpd(8) for
           details of the format of such addresses.

   -X      Do not connect to a AgentX master agent

           Allows one to specify  any  token  ("name")  supported  in  the
           snmptrapd.conf  file  and  sets its value to "value". Overrides
           the  corresponding  token  in  the  snmptrapd.conf  file.   See
           snmptrapd.conf(5) for the full list of tokens.


   snmptrapd   interprets  format  strings  similarly  to  printf(3).   It
   understands the following formatting sequences:

       %%  a literal %

       %a  the contents of the agent-addr field of the PDU (v1 TRAPs only)

       %A  the hostname corresponding to the contents  of  the  agent-addr
           field  of  the PDU, if available, otherwise the contents of the
           agent-addr field of the PDU (v1 TRAPs only).

       %b  PDU transport address (Note: this is not  necessarily  an  IPv4
           Something like "[UDP: []:23456->[]]"

       %B  PDU  source hostname if available, otherwise PDU source address
           (see note above)

       %E  SNMPv3 context engine id

       %h  current hour on the local system

       %H  the hour field from the sysUpTime.0 varbind

       %j  current minute on the local system

       %J  the minute field from the sysUpTime.0 varbind

       %k  current second on the local system

       %K  the seconds field from the sysUpTime.0 varbind

       %l  current day of month on the local system

       %L  the day of month field from the sysUpTime.0 varbind

       %m  current (numeric) month on the local system

       %M  the numeric month field from the sysUpTime.0 varbind

       %N  enterprise string

       %P  security information from the PDU (community name  for  v1/v2c,
           user and context for v3)

       %q  trap sub-type (numeric, in decimal)

       %s  SNMP version number (0: v1, 1: v2c, 2: v3)

       %S  SNMPv3 security model version number

       %t  decimal  number of seconds since the operating system epoch (as
           returned by time(2))

       %T  the value of the sysUpTime.0 varbind in seconds

       %u  SNMPv3 security name, or v1/v2c community name

       %v  list of variable-bindings from the notification payload.  These
           will  be  separated  by a tab, or by a comma and a blank if the
           alternate form is requested See also %V

       %V  specifies  the  variable-bindings  separator.  This   takes   a
           sequence  of  characters, up to the next % (to embed a % in the
           string, use \%)

       %w  trap type (numeric, in decimal)

       %W  trap description

       %y  current year on the local system

       %Y  the year field from the sysUpTime.0 varbind

   In addition to these values, an optional field width and precision  may
   also  be  specified  ,  just  as  in  printf(3),  and a flag value. The
   following flags are supported:

       -   left justify

       0   use leading zeros

       #   use alternate form

   The "use alternate form" flag changes the behavior  of  various  format
   string sequences:

          Time information will be displayed based on GMT (rather than the
          local timezone)

          The variable-bindings will be  a  comma-separated  list  (rather
          than a tab-separated one)

          The  system  uptime  will be broken down into a human-meaningful
          format (rather than being a simple integer)

   To get a message like "14:03 TRAP3.1 from" you could use
   something like this:

          snmptrapd -P -F "%02.2h:%02.2j TRAP%w.%q from %A\n"

   If you want the same thing but in GMT rather than local time, use

          snmptrapd -P -F "%#02.2h:%#02.2j TRAP%w.%q from %A\n"


   By default, snmptrapd listens for incoming SNMP TRAP and INFORM packets
   on UDP port 162 on all IPv4 interfaces.  However,  it  is  possible  to
   modify  this behaviour by specifying one or more listening addresses as
   arguments  to  snmptrapd.   See  the  snmpd(8)  manual  page  for  more
   information about the format of listening addresses.


   As   of   net-snmp   5.0,   the   snmptrapd  application  supports  the
   NOTIFICATION-LOG-MIB.  It does  this  by  opening  an  AgentX  subagent
   connection  to  the master snmpd agent and registering the notification
   log tables.  As long as the snmpd application is started first, it will
   attach  itself  to  it  and  thus  you  should be able to view the last
   recorded notifications via  the  nlmLogTable  and  nlmLogVariableTable.
   See the snmptrapd.conf file and the "doNotRetainNotificationLogs" token
   for turning off this support.  See the  NOTIFICATION-LOG-MIB  for  more
   details about the MIB itself.


   See the snmptrapd.conf(5) manual page.


   snmpcmd(1),    snmpd(8),   printf(3),   snmptrapd.conf(5),   syslog(8),
   traptoemail(1), variables(5)


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