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  Retrieve a subtree of management values using SNMP GETBULK requests




      snmpbulkwalk is an SNMP application that uses SNMP GETBULK requests  to
      query a network entity efficiently for a tree of information.
      An  object identifier (OID) may be given on the command line.  This OID
      specifies which portion of the object identifier space will be searched
      using  GETBULK  requests.  All variables in the subtree below the given
      OID are queried and their values presented to the user.  Each  variable
      name is given in the format specified in variables(5).  If no OID argu-
      ment is present, snmpbulkwalk will search MIB-2.
      If the network entity has an error processing the  request  packet,  an
      error  packet  will be returned and a message will be shown, helping to
      pinpoint why the request was malformed.
      If the tree search causes attempts to search beyond the end of the MIB,
      the message "End of MIB" will be displayed.


      -Cc     Do  not  check  whether the returned OIDs are increasing.  Some
              agents (LaserJets are an example) return OIDs out of order, but
              can  complete  the  walk anyway.  Other agents return OIDs that
              are out of order and can cause  snmpbulkwalk  to  loop  indefi-
              nitely.  By default, snmpbulkwalk tries to detect this behavior
              and warns you when it hits an agent acting illegally.  Use  -Cc
              to turn off this behaviour.
      -Ci     Include  the given OID in the search range.  Normally snmpbulk-
              walk uses GETBULK requests starting with the OID you  specified
              and  returns all results in the MIB tree after that OID.  Some-
              times, you may wish to include the OID specified on the command
              line  in  the  printed results if it is a valid OID in the tree
              itself.  This option lets you do this.
              Set the non-repeaters field in the GETBULK PDUs.   This  speci-
              fies  the number of supplied variables that should not be iter-
              ated over.  The default is 0.
      -Cp     Upon completion of the walk,  print  the  number  of  variables
              Set the max-repetitions field in the GETBULK PDUs.  This speci-
              fies the maximum number of iterations over the repeating  vari-
              ables.  The default is 10.
      In  addition  to  these  options, snmpbulkwalk takes the common options
      described in the snmpcmd(1) manual page.


      The command:
      snmpbulkwalk -v2c -Os -c public zeus system
      will retrieve all of the variables under system:
      sysDescr.0 = STRING: "SunOS zeus.net.cmu.edu 4.1.3_U1 1 sun4m"
      sysObjectID.0 = OID: enterprises.hp.nm.hpsystem.10.1.1
      sysUpTime.0 = Timeticks: (155274552) 17 days, 23:19:05
      sysContact.0 = STRING: ""
      sysName.0 = STRING: "zeus.net.cmu.edu"
      sysLocation.0 = STRING: ""
      sysServices.0 = INTEGER: 72
      In contrast to snmpwalk, this information will typically be gathered in
      a  single  transaction  with the agent, rather than one transaction per
      variable found.  snmpbulkwalk is thus more efficient in terms  of  net-
      work  utilisation,  which  may  be especially important when retrieving
      large tables.


      As the name implies, snmpbulkwalk utilizes the  SNMP  GETBULK  message,
      which is not available in SNMP v1.