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SNMP(3)		      User Contributed Perl Documentation	       SNMP(3)

NAME
       SNMP - The Perl5	'SNMP' Extension Module	for the	Net-SNMP SNMP package.

SYNOPSIS
	use SNMP;
	...
	$sess =	new SNMP::Session(DestHost => localhost, Community => public);
	$val = $sess->get('sysDescr.0');
	...
	$vars =	new SNMP::VarList([sysDescr,0],	[sysContact,0],	[sysLocation,0]);
	@vals =	$sess->get($vars);
	...
	$vb = new SNMP::Varbind();
	do {
	   $val	= $sess->getnext($vb);
	   print "@{$vb}\n";
	} until	($sess->{ErrorNum});
	...
	$SNMP::save_descriptions = 1;
	SNMP::initMib(); # assuming mib	is not already loaded
	print "$SNMP::MIB{sysDescr}{description}\n";

DESCRIPTION
       Note: The perl SNMP 5.0 module which comes with net-snmp	5.0 and	higher
       is different than previous versions in a	number of ways.	 Most
       importantly, it behaves like a proper net-snmp application and calls
       init_snmp properly, which means it will read configuration files	and
       use those defaults where	appropriate automatically parse	MIB files,
       etc.  This will likely affect your perl applications if you have, for
       instance, default values	set up in your snmp.conf file (as the perl
       module will now make use	of those defaults).  The documentation,
       however,	has sadly not been updated yet (aside from this	note), nor is
       the read_config default usage implementation fully complete.

       The basic operations of the SNMP	protocol are provided by this module
       through an object oriented interface for	modularity and ease of use.
       The primary class is SNMP::Session which	encapsulates the persistent
       aspects of a connection between the management application and the
       managed agent. Internally the class is implemented as a blessed hash
       reference. This class supplies 'get', 'getnext',	'set', 'fget', and
       'fgetnext' method calls.	The methods take a variety of input argument
       formats and support both	synchronous and	asynchronous operation through
       a polymorphic API (i.e.,	method behaviour varies	dependent on args
       passed -	see below).

SNMP::Session
       $sess = new SNMP::Session(DestHost => 'host', ...)

       The following arguments may be passed to	new as a hash.

   Basic Options
       DestHost
	   Hostname or IP address of the SNMP agent you	want to	talk to.
	   Specified in	Net-SNMP formatted agent addresses.  These addresses
	   typically look like one of the following:

	     localhost
	     tcp:localhost
	     tls:localhost
	     tls:localhost:9876
	     udp6:[::1]:9876
	     unix:/some/path/to/file/socket

	   Defaults to 'localhost'.

       Version
	   SNMP	version	to use.

	   The default is taken	from library configuration - probably 3	[1, 2
	   (same as 2c), 2c, 3].

       Timeout
	   The number of micro-seconds to wait before resending	a request.

	   The default is '1000000'

       Retries
	   The number of times to retry	a request.

	   The default is '5'

       RetryNoSuch
	   If enabled NOSUCH errors in 'get' pdus will be repaired, removing
	   the varbind in error, and resent - undef will be returned for all
	   NOSUCH varbinds, when set to	'0' this feature is disabled and the
	   entire get request will fail	on any NOSUCH error (applies to	v1
	   only)

	   The default is '0'.

   SNMPv3/TLS Options
       OurIdentity
	   Our X.509 identity to use, which should either be a fingerprint or
	   the filename	that holds the certificate.

       TheirIdentity
	   The remote server's identity	to connect to, specified as eihter a
	   fingerprint or a file name.	Either this must be specified, or the
	   hostname below along	with a trust anchor.

       TheirHostname
	   The remote server's hostname	that is	expected.  If their
	   certificate was signed by a CA then their hostname presented	in the
	   certificate must match this value or	the connection fails to	be
	   established (to avoid man-in-the-middle attacks).

       TrustCert
	   A trusted certificate to use	a trust	anchor (like a CA certificate)
	   for verifying a remote server's certificate.	 If a CA certificate
	   is used to validate a certificate then the TheirHostname parameter
	   must	also be	specified to ensure their presente hostname in the
	   certificate matches.

   SNMPv3/USM Options
       SecName
	   The SNMPv3 security name to use (most for SNMPv3 with USM).

	   The default is 'initial'.

       SecLevel
	   The SNMPv3 security level to	use [noAuthNoPriv, authNoPriv,
	   authPriv] (v3)

	   The default is 'noAuthNoPriv'.

       SecEngineId
	   The SNMPv3 security engineID	to use (if the snmpv3 security model
	   needs it; for example USM).

	   The default is <none>, security engineID and	it will	be probed if
	   not supplied	(v3)

       ContextEngineId
	   The SNMPv3 context engineID to use.

	   The default is the <none> and will be set either to the SecEngineId
	   value if set	or discovered or will be discovered in other ways if
	   using TLS (RFC5343 based discovery).

       Context
	   The SNMPv3 context name to use.

	   The default is '' (an empty string)

       AuthProto
	   The SNMPv3/USM authentication protocol to use [MD5, SHA].

	   The default is 'MD5'.

       AuthPass
	   The SNMPv3/USM authentication passphrase to use.

	   default <none>, authentication passphrase

       PrivProto
	   The SNMPv3/USM privacy protocol to use [DES,	AES].

	   The default is 'DES'.

       PrivPass
	   The SNMPv3/USM privacy passphrase to	use.

	   default <none>, privacy passphrase (v3)

       AuthMasterKey
       PrivMasterKey
       AuthLocalizedKey
       PrivLocalizedKey
	   Directly specified SNMPv3 USM user keys (used if you	want to
	   specify the keys instead of deriving	them from a password as
	   above).

   SNMPv1 and SNMPv2c Options
       Community
	   For SNMPv1 and SNMPv2c, the clear-text community name to use.

	   The default is 'public'.

   Other Configuration Options
       VarFormats
	   default 'undef', used by 'fget[next]', holds	an hash	reference of
	   output value	formatters, (e.g., {<obj> => <sub-ref>,	... }, <obj>
	   must	match the <obj>	and format used	in the get operation. A
	   special <obj>, '*', may be used to apply all	<obj>s,	the supplied
	   sub is called to translate the value	to a new format. The sub is
	   called passing the Varbind as the arg

       TypeFormats
	   default 'undef', used by 'fget[next]', holds	an hash	reference of
	   output value	formatters, (e.g., {<type> => <sub-ref>, ... },	the
	   supplied sub	is called to translate the value to a new format,
	   unless a VarFormat mathces first (e.g.,
	   $sess->{TypeFormats}{INTEGER} = \&mapEnum();	although this can be
	   done	more efficiently by enabling $SNMP::use_enums or session
	   creation param 'UseEnums')

       UseLongNames
	   defaults to the value of SNMP::use_long_names at time of session
	   creation. set to non-zero to	have <tags> for	'getnext' methods
	   generated preferring	longer Mib name	convention (e.g.,
	   system.sysDescr vs just sysDescr)

       UseSprintValue
	   defaults to the value of SNMP::use_sprint_value at time of session
	   creation. set to non-zero to	have return values for 'get' and
	   'getnext' methods formatted with the	libraries snprint_value
	   function. This will result in certain data types being returned in
	   non-canonical format	Note: values returned with this	option set may
	   not be appropriate for 'set'	operations (see	discussion of value
	   formats in <vars> description section)

       UseEnums
	   defaults to the value of SNMP::use_enums at time of session
	   creation. set to non-zero to	have integer return values converted
	   to enumeration identifiers if possible, these values	will also be
	   acceptable when supplied to 'set' operations

       UseNumeric
	   defaults to the value of SNMP::use_numeric at time of session
	   creation. set to non-zero to	have <tags> for	get methods returned
	   as numeric OID's rather than	descriptions.  UseLongNames will be
	   set so that the full	OID is returned	to the caller.

       BestGuess
	   defaults to the value of SNMP::best_guess at	time of	session
	   creation. this setting controls how <tags> are parsed.  setting to
	   0 causes a regular lookup.  setting to 1 causes a regular
	   expression match (defined as	-Ib in snmpcmd)	and setting to 2
	   causes a random access lookup (defined as -IR in snmpcmd).

       NonIncreasing
	   defaults to the value of SNMP::non_increasing at time of session
	   creation. this setting controls if a	non-increasing OID during
	   bulkwalk will causes	an error. setting to 0 causes the default
	   behaviour (which may, in very badly performing agents, result in a
	   never-ending	loop).	setting	to 1 causes an error (OID not
	   increasing) when this error occur.

       ErrorStr
	   read-only, holds the	error message assoc. w/	last request

       ErrorNum
	   read-only, holds the	snmp_err or staus of last request

       ErrorInd
	   read-only, holds the	snmp_err_index when appropriate

       Private variables:

       DestAddr
	   internal field used to hold the translated DestHost field

       SessPtr
	   internal field used to cache	a created session structure

       RemotePort
	   Obsolete.  Please use the DestHost specifier	to indicate the
	   hostname and	port combination instead of this paramet.

   SNMP::Session methods
       $sess->update(<fields>)
	   Updates the SNMP::Session object with the values fields passed in
	   as a	hash list (similar to new(<fields>)) (WARNING! not fully
	   implemented)

       $sess->get(<vars> [,<callback>])
	   do SNMP GET,	multiple <vars>	formats	accepted.  for syncronous
	   operation <vars> will be updated with value(s) and type(s) and will
	   also	return retrieved value(s). If <callback> supplied method will
	   operate asynchronously

       $sess->fget(<vars> [,<callback>])
	   do SNMP GET like 'get' and format the values	according the handlers
	   specified in	$sess->{VarFormats} and	$sess->{TypeFormats}

       $sess->getnext(<vars> [,<callback>])
	   do SNMP GETNEXT, multiple <vars> formats accepted, returns
	   retrieved value(s), <vars> passed as	arguments are updated to
	   indicate next lexicographical <obj>,<iid>,<val>, and	<type>

	   Note: simple	string <vars>,(e.g., 'sysDescr.0') form	is not
	   updated. If <callback> supplied method will operate asynchronously

       $sess->fgetnext(<vars> [,<callback>])
	   do SNMP GETNEXT like	getnext	and format the values according	the
	   handlers specified in $sess->{VarFormats} and $sess->{TypeFormats}

       $sess->set(<vars> [,<callback>])
	   do SNMP SET,	multiple <vars>	formats	accepted.  the value field in
	   all <vars> formats must be in a canonical format (i.e., well	known
	   format) to ensure unambiguous translation to	SNMP MIB data value
	   (see	discussion of canonical	value format <vars> description
	   section), returns snmp_errno. If <callback> supplied	method will
	   operate asynchronously

       $sess->getbulk(<non-repeaters>, <max-repeaters>,	<vars>)
	   do an SNMP GETBULK, from the	list of	Varbinds, the single next
	   lexico instance is fetched for the first n Varbinds as defined by
	   <non-repeaters>. For	remaining Varbinds, the	m lexico instances are
	   retrieved each of the remaining Varbinds, where m is
	   <max-repeaters>.

       $sess->bulkwalk(<non-repeaters>,	<max-repeaters>, <vars>	[,<callback>])
	   Do a	"bulkwalk" of the list of Varbinds.  This is done by sending a
	   GETBULK request (see	getbulk() above) for the Varbinds.  For	each
	   requested variable, the response is examined	to see if the next
	   lexico instance has left the	requested sub-tree.  Any further
	   instances returned for this variable	are ignored, and the walk for
	   that	sub-tree is considered complete.

	   If any sub-trees were not completed when the	end of the responses
	   is reached, another request is composed, consisting of the
	   remaining variables.	 This process is repeated until	all sub-trees
	   have	been completed,	or too many packets have been exchanged	(to
	   avoid loops).

	   The bulkwalk() method returns an array containing an	array of
	   Varbinds, one for each requested variable, in the order of the
	   variable requests.  Upon error, bulkwalk() returns undef and	sets
	   $sess->ErrorStr and $sess->ErrorNum.	 If a callback is supplied,
	   bulkwalk() returns the SNMP request id, and returns immediately.
	   The callback	will be	called with the	supplied argument list and the
	   returned variables list.

	   Note: Because the client must "discover" that the tree is complete
	   by comparing	the returned variables with those that were requested,
	   there is a potential	"gotcha" when using the	max-repeaters value.
	   Consider the	following code to print	a list of interfaces and byte
	   counts:

	       $numInts	= $sess->get('ifNumber.0');
	       ($desc, $in, $out) = $sess->bulkwalk(0, $numInts,
			     [['ifDescr'], ['ifInOctets'], ['ifOutOctets']]);

	       for $i (0..($numInts - 1)) {
		   printf "Interface %4s: %s inOctets, %s outOctets\n",
			     $$desc[$i]->val, $$in[$i]->val, $$out[$i]->val;
	       }

	   This	code will produce *two*	requests to the	agent -- the first to
	   get the interface values, and the second to discover	that all the
	   information was in the first	packet.	 To get	around this, use
	   '$numInts + 1' for the max_repeaters	value.	This asks the agent to
	   include one additional (unrelated) variable that signals the	end of
	   the sub-tree, allowing bulkwalk() to	determine that the request is
	   complete.

       $results	= $sess->gettable(<TABLE OID>, <OPTIONgt)
	   This	will retrieve an entire	table of data and return a hash
	   reference to	that data.  The	returned hash reference	will have
	   indexes of the OID suffixes for the index data as the key.  The
	   value for each entry	will be	another	hash containing	the data for a
	   given row.  The keys	to that	hash will be the column	names, and the
	   values will be the data.

	   Example:

	     #!/usr/bin/perl

	     use SNMP;
	     use Data::Dumper;

	     my	$s = new SNMP::Session(DestHost	=> 'localhost');

	     print Dumper($s->gettable('ifTable'));

	   On my machine produces:

	     $VAR1 = {
		       '6' => {
				'ifMtu'	=> '1500',
				'ifPhysAddress'	=> 'PV',
				# ...
				'ifInUnknownProtos' => '0'
			      },
		       '4' => {
				'ifMtu'	=> '1480',
				'ifPhysAddress'	=> '',
				# ...
				'ifInUnknownProtos' => '0'
			      },
		       # ...
		      };

	   By default, it will try to do as optimized retrieval	as possible.
	   It'll request multiple columns at once, and use GETBULK if
	   possible.  A	few options may	be specified by	passing	in an OPTIONS
	   hash	containing various parameters:

	   noindexes =>	1
	       Instructs the code not to parse the indexes and place the
	       results in the second hash.  If you don't need the index	data,
	       this will be faster.

	   columns => [	colname1, ... ]
	       This specifies which columns to collect.	 By default, it	will
	       try to collect all the columns defined in the MIB table.

	   repeat => COUNT
	       Specifies a GETBULK repeat COUNT.  IE, it will request this
	       many varbinds back per column when using	the GETBULK operation.
	       Shortening this will mean smaller packets which may help	going
	       through some systems.  By default, this value is	calculated and
	       attempts	to guess at what will fit all the results into 1000
	       bytes.  This calculation	is fairly safe,	hopefully, but you can
	       either raise or lower the number	using this option if desired.
	       In lossy	networks, you want to make sure	that the packets don't
	       get fragmented and lowering this	value is one way to help that.

	   nogetbulk =>	1
	       Force the use of	GETNEXT	rather than GETBULK.  (always true for
	       SNMPv1, as it doesn't have GETBULK anyway).  Some agents	are
	       great implementers of GETBULK and this allows you to force the
	       use of GETNEXT operations instead.

	   callback => \&subroutine
	   callback => [\&subroutine, optarg1, optarg2,	...]
	       If a callback is	specified, gettable will return	quickly
	       without returning results.  When	the results are	finally
	       retrieved the callback subroutine will be called	(see the other
	       sections	defining callback behaviour and	how to make use	of
	       SNMP::MainLoop which is required	fro this to work).  An
	       additional argument of the normal hash result will be added to
	       the callback subroutine arguments.

	       Note 1: internally, the gettable	function uses it's own
	       callbacks which are passed to getnext/getbulk as	appropriate.

	       Note 2: callback	support	is only	available in the SNMP module
	       version 5.04 and	above.	To test	for this in code intending to
	       support both versions prior to 5.04 and 5.04 and	up, the
	       following should	work:

		 if ($response = $sess->gettable('ifTable', callback =>	\&my_sub)) {
		     # got a response, gettable	doesn't	support	callback
		     my_sub($response);
		     $no_mainloop = 1;
		 }

	       Deciding	on whether to use SNMP::MainLoop is left as an
	       exercise	to the reader since it depends on whether your code
	       uses other callbacks as well.

SNMP::TrapSession
       $sess = new SNMP::Session(DestHost => 'host', ...)

       supports	all applicable fields from SNMP::Session (see above)

   SNMP::TrapSession methods
       $sess->trap(enterprise, agent, generic, specific, uptime, <vars>)
	       $sess->trap(enterprise=>'.1.3.6.1.4.1.2021', # or 'ucdavis' [default]
			   agent => '127.0.0.1', # or 'localhost',[dflt	1st intf on host]
			   generic => specific,	 # can be omitted if 'specific'	supplied
			   specific => 5,	 # can be omitted if 'generic' supplied
			   uptime => 1234,	 # dflt	to localhost uptime (0 on win32)
			   [[ifIndex, 1, 1],[sysLocation, 0, "here"]]);	# optional vars
									# always last

       trap(oid, uptime, <vars>) - v2 format
	       $sess->trap(oid => 'snmpRisingAlarm',
			   uptime => 1234,
			   [[ifIndex, 1, 1],[sysLocation, 0, "here"]]);	# optional vars
									# always last

Acceptable variable formats:
       <vars> may be one of the	following forms:

       SNMP::VarList
	   represents an array of MIB objects to get or	set, implemented as a
	   blessed reference to	an array of SNMP::Varbinds, (e.g.,
	   [<varbind1>,	<varbind2>, ...])

       SNMP::Varbind
	   represents a	single MIB object to get or set, implemented as	a
	   blessed reference to	a 4 element array; [<obj>, <iid>, <val>,
	   <type>].

	   <obj>
	       one of the following forms:

	       1)  leaf	identifier (e.g., 'sysDescr') assumed to be unique for
		   practical purposes

	       2)  fully qualified identifier (e.g.,
		   '.iso.org.dod.internet.mgmt.mib-2.system.sysDescr')

	       3)  fully qualified, dotted-decimal, numeric OID	(e.g.,
		   '.1.3.6.1.2.1.1.1')

	   <iid>
	       the dotted-decimal, instance identifier.	for scalar MIB objects
	       use '0'

	   <val>
	       the SNMP	data value retrieved from or being set to the agents
	       MIB. for	(f)get(next) operations	<val> may have a variety of
	       formats as determined by	session	and package settings. However
	       for set operations the <val> format must	be canonical to	ensure
	       unambiguous translation.	The canonical forms are	as follows:

	       OBJECTID
		   dotted-decimal (e.g., .1.3.6.1.2.1.1.1)

	       OCTETSTR
		   perl	scalar containing octets

	       INTEGER
		   decimal signed integer (or enum)

	       NETADDR
		   dotted-decimal

	       IPADDR
		   dotted-decimal

	       COUNTER
		   decimal unsigned integer

	       COUNTER64
		   decimal unsigned integer

	       GAUGE
		   decimal unsigned integer

	       UINTEGER
		   decimal unsigned integer

	       TICKS
		   decimal unsigned integer

	       OPAQUE
		   perl	scalar containing octets

	       NULL
		   perl	scalar containing nothing

	   <type>
	       SNMP data type (see list	above),	this field is populated	by
	       'get' and 'getnext' operations. In some cases the programmer
	       needs to	populate this field when passing to a 'set' operation.
	       this field need not be supplied when the	attribute indicated by
	       <tag> is	already	described by loaded Mib	modules. for 'set's,
	       if a numeric OID	is used	and the	object is not currently	in the
	       loaded Mib, the <type> field must be supplied

       simple string
	   light weight	form of	<var> used to 'set' or 'get' a single
	   attribute without constructing an SNMP::Varbind.  stored in a perl
	   scalar, has the form	'<tag>.<iid>', (e.g., 'sysDescr.0'). for 'set'
	   operations the value	is passed as a second arg. Note: This argument
	   form	is not updated in get[next] operations as are the other	forms.

Acceptable callback formats
       <callback> may be one of	the following forms:

       without arguments
	   \&subname
	   sub { ... }
       or with arguments
	   [ \&subname,	$arg1, ... ]
	   [ sub { ... }, $arg1, ... ]
	   [ "method", $obj, $arg1, ...	]

       callback	will be	called when response is	received or timeout occurs.
       the last	argument passed	to callback will be a SNMP::VarList reference.
       In case of timeout the last argument will be undef.

       &SNMP::MainLoop([<timeout>, [<callback>]])
	   to be used with async SNMP::Session calls. MainLoop must be called
	   after initial async calls so	return packets from the	agent will not
	   be processed.  If no	args supplied this function enters an infinite
	   loop	so program must	be exited in a callback	or externally
	   interrupted.	If <timeout(sic)

       &SNMP::finish()
	   This	function, when called from an SNMP::MainLoop() callback
	   function, will cause	the current SNMP::MainLoop() to	return after
	   the callback	is completed.  finish()	can be used to terminate an
	   otherwise-infinite MainLoop.	 A new MainLoop() instance can then be
	   started to handle further requests.

SNMP package variables and functions
       $SNMP::VERSION
	   the current version specifier (e.g.,	3.1.0)

       $SNMP::auto_init_mib
	   default '1',	set to 0 to disable automatic reading of the MIB upon
	   session creation. set to non-zero to	call initMib at	session
	   creation which will result in MIB loading according to Net-SNMP
	   env.	variables (see man mib_api)

       $SNMP::verbose
	   default '0',	controls warning/info output of	SNMP module, 0 => no
	   output, 1 =>	enables	warning/info output from SNMP module itself
	   (is also controlled by SNMP::debugging - see	below)

       $SNMP::use_long_names
	   default '0',	set to non-zero	to enable the use of longer Mib
	   identifiers.	see translateObj. will also influence the formatting
	   of <tag> in varbinds	returned from 'getnext'	operations. Can	be set
	   on a	per session basis (UseLongNames)

       $SNMP::use_sprint_value
	   default '0',	set to non-zero	to enable formatting of	response
	   values using	the snmp libraries snprint_value function. can also be
	   set on a per	session	basis (see UseSprintValue) Note: returned
	   values may not be suitable for 'set'	operations

       $SNMP::use_enums
	   default '0',set non-zero to return values as	enums and allow	sets
	   using enums where appropriate. integer data will still be accepted
	   for set operations. can also	be set on a per	session	basis (see
	   UseEnums)

       $SNMP::use_numeric
	   default to '0',set to non-zero to have <tags> for 'get' methods
	   returned as numeric OID's rather than descriptions.	UseLongNames
	   will	be set so that the entire OID will be returned.	 Set on	a per-
	   session basis (see UseNumeric).

       $SNMP::best_guess
	   default '0'.	 This setting controls how <tags> are parsed.  Setting
	   to 0	causes a regular lookup.  Setting to 1 causes a	regular
	   expression match (defined as	-Ib in snmpcmd)	and setting to 2
	   causes a random access lookup (defined as -IR in snmpcmd).  Can
	   also	be set on a per	session	basis (see BestGuess)

       $SNMP::save_descriptions
	   default '0',set non-zero to have mib	parser save attribute
	   descriptions. must be set prior to mib initialization

       $SNMP::debugging
	   default '0',	controls debugging output level	within SNMP module and
	   libsnmp

	   1.  enables 'SNMP::verbose' (see above)

	   2.  level 1 plus snmp_set_do_debugging(1)

	   3.  level 2 plus snmp_set_dump_packet(1)

       $SNMP::dump_packet
	   default '0',	set [non-]zero to independently	set
	   snmp_set_dump_packet()

       SNMP::register_debug_tokens()
	   Allows to register one or more debug	tokens,	just like the -D
	   option of snmpd.  Each debug	token enables a	group of debug
	   statements. An example:
	   SNMP::register_debug_tokens("tdomain,netsnmp_unix");

%SNMP::MIB
       a tied hash to access parsed MIB	information. After the MIB has been
       loaded this hash	allows access to to the	parsed in MIB meta-data(the
       structure of the	MIB (i.e., schema)). The hash returns blessed
       references to SNMP::MIB::NODE objects which represent a single MIB
       attribute. The nodes can	be fetched with	multiple 'key' formats - the
       leaf name (e.g.,sysDescr) or fully/partially qualified name (e.g.,
       system.sysDescr)	or fully qualified numeric OID.	The returned node
       object supports the following fields:

       objectID
	   dotted decimal fully	qualified OID

       label
	   leaf	textual	identifier (e.g., 'sysDescr')

       subID
	   leaf	numeric	OID component of objectID (e.g., '1')

       moduleID
	   textual identifier for module (e.g.,	'RFC1213-MIB')

       parent
	   parent node

       children
	   array reference of children nodes

       nextNode
	   next	lexico node (BUG!does not return in lexico order)

       type
	   returns application type (see getType for values)

       access
	   returns ACCESS (ReadOnly, ReadWrite,	WriteOnly, NoAccess, Notify,
	   Create)

       status
	   returns STATUS (Mandatory, Optional,	Obsolete, Deprecated)

       syntax
	   returns 'textualConvention' if defined else 'type'

       textualConvention
	   returns TEXTUAL-CONVENTION

       TCDescription
	   returns the TEXTUAL-CONVENTION's DESCRIPTION	field.

       units
	   returns UNITS

       hint
	   returns HINT

       enums
	   returns hash	ref {tag => num, ...}

       ranges
	   returns array ref of	hash ref [{low => num, high => num}, ...]

       description
	   returns DESCRIPTION ($SNMP::save_descriptions must be set prior to
	   MIB initialization/parsing)

       reference
	   returns the REFERENCE clause

       indexes
	   returns the objects in the INDEX clause

       implied
	   returns true	if the last object in the INDEX	is IMPLIED

MIB Functions
       &SNMP::setMib(<file>)
	   allows dynamic parsing of the mib and explicit specification	of mib
	   file	independent of environment variables. called with no args acts
	   like	initMib, loading MIBs indicated	by environment variables (see
	   Net-SNMP mib_api docs). passing non-zero second arg forces previous
	   mib to be freed and replaced	(Note: second arg not working since
	   freeing previous Mib	is more	involved than before).

       &SNMP::initMib()
	   calls library init_mib function if Mib not already loaded - does
	   nothing if Mib already loaded. will parse directories and load
	   modules according to	environment variables described	in Net-SNMP
	   documentations.  (see man mib_api, MIBDIRS, MIBS, MIBFILE(S), etc.)

       &SNMP::addMibDirs(<dir>,...)
	   calls library add_mibdir for	each directory supplied. will cause
	   directory(s)	to be added to internal	list and made available	for
	   searching in	subsequent loadModules calls

       &SNMP::addMibFiles(<file>,...)
	   calls library read_mib function. The	file(s)	supplied will be read
	   and all Mib module definitions contained therein will be added to
	   internal mib	tree structure

       &SNMP::loadModules(<mod>,...)
	   calls library read_module function. The module(s) supplied will be
	   searched for	in the current mibdirs and and added to	internal mib
	   tree	structure. Passing special <mod>, 'ALL', will cause all	known
	   modules to be loaded.

       &SNMP::unloadModules(<mod>,...)
	   *Not	Implemented*

       &SNMP::translateObj(<var>[,arg,[arg]])
	   will	convert	a text obj tag to an OID and vice-versa.  Any iid
	   suffix is retained numerically.  Default behaviour when converting
	   a numeric OID to text form is to return leaf	identifier only
	   (e.g.,'sysDescr') but when $SNMP::use_long_names is non-zero	or a
	   non-zero second arg is supplied it will return a longer textual
	   identifier.	An optional third argument of non-zero will cause the
	   module name to be prepended to the text name	(e.g.
	   'SNMPv2-MIB::sysDescr').  When converting a text obj, the
	   $SNMP::best_guess option is used.  If no Mib	is loaded when called
	   and $SNMP::auto_init_mib is enabled then the	Mib will be loaded.
	   Will	return 'undef' upon failure.

       &SNMP::getType(<var>)
	   return SNMP data type for given textual identifier OBJECTID,
	   OCTETSTR, INTEGER, NETADDR, IPADDR, COUNTER GAUGE, TIMETICKS,
	   OPAQUE, or undef

       &SNMP::mapEnum(<var>)
	   converts integer value to enumertion	tag defined in Mib or converts
	   tag to integer depending on input. the function will	return the
	   corresponding integer value *or* tag	for a given MIB	attribute and
	   value. The function will sense which	direction to perform the
	   conversion. Various arg formats are supported

	   $val	= SNMP::mapEnum($varbind);
	       where $varbind is SNMP::Varbind or equiv.  note:	$varbind will
	       be updated

	   $val	= SNMP::mapEnum('ipForwarding',	'forwarding');
	   $val	= SNMP::mapEnum('ipForwarding',	1);

Exported SNMP utility functions
       Note: utility functions do not support async operation yet.

       &snmp_get()
	   takes args of SNMP::Session::new followed by	those of
	   SNMP::Session::get

       &snmp_getnext()
	   takes args of SNMP::Session::new followed by	those of
	   SNMP::Session::getnext

       &snmp_set()
	   takes args of SNMP::Session::new followed by	those of
	   SNMP::Session::set

       &snmp_trap()
	   takes args of SNMP::TrapSession::new	followed by those of
	   SNMP::TrapSession::trap

Trouble	Shooting
       If problems occur there are number areas	to look	at to narrow down the
       possibilities.

       The first step should be	to test	the Net-SNMP installation
       independently from the Perl5 SNMP interface.

       Try running the apps from the Net-SNMP distribution.

       Make sure your agent (snmpd) is running and properly configured with
       read-write access for the community you are using.

       Ensure that your	MIBs are installed and enviroment variables are	set
       appropriately (see man mib_api)

       Be sure to remove old net-snmp installations and	ensure headers and
       libraries from old CMU installations are	not being used by mistake.

       If the problem occurs during compilation/linking	check that the snmp
       library being linked is actually	the Net-SNMP library (there have been
       name conflicts with existing snmp libs).

       Also check that the header files	are correct and	up to date.

       Sometimes compiling the Net-SNMP	library	with
       'position-independent-code' enabled is required (HPUX specifically).

       If you cannot resolve the problem you can post to
       comp.lang.perl.modules or
       net-snmp-users@net-snmp-users@lists.sourceforge.net

       please give sufficient information to analyze the problem (OS type,
       versions	for OS/Perl/Net-SNMP/compiler, complete	error output, etc.)

Acknowledgements
       Many thanks to all those	who supplied patches, suggestions and
       feedback.

	Joe Marzot (the	original author)
	Wes Hardaker and the net-snmp-coders
	Dave Perkins
	Marcel Wiget
	David Blackburn
	John Stofell
	Gary Hayward
	Claire Harrison
	Achim Bohnet
	Doug Kingston
	Jacques	Vidrine
	Carl Jacobsen
	Wayne Marquette
	Scott Schumate
	Michael	Slifcak
	Srivathsan Srinivasagopalan
	Bill Fenner
	Jef Peeraer
	Daniel Hagerty
	Karl "Rat" Schilke and Electric	Lightwave, Inc.
	Perl5 Porters
	Alex Burger

       Apologies to any/all who's patch/feature/request	was not	mentioned or
       included	- most likely it was lost when paying work intruded on my fun.
       Please try again	if you do not see a desired feature. This may actually
       turn out	to be a	decent package with such excellent help	and the	fact
       that I have more	time to	work on	it than	in the past.

AUTHOR
       bugs, comments, questions to net-snmp-users@lists.sourceforge.net

Copyright
	    Copyright (c) 1995-2000 G. S. Marzot. All rights reserved.
	    This program is free software; you can redistribute	it and/or
	    modify it under the	same terms as Perl itself.

	    Copyright (c) 2001-2002 Networks Associates	Technology, Inc.  All
	    Rights Reserved.  This program is free software; you can
	    redistribute it and/or modify it under the same terms as Perl
	    itself.

POD ERRORS
       Hey! The	above document had some	coding errors, which are explained
       below:

       Around line 1722:
	   '=item' outside of any '=over'

       Around line 1728:
	   You forgot a	'=back'	before '=head2'

perl v5.24.1			  2014-12-08			       SNMP(3)

NAME | SYNOPSIS | DESCRIPTION | SNMP::Session | SNMP::TrapSession | Acceptable variable formats: | Acceptable callback formats | SNMP package variables and functions | %SNMP::MIB | MIB Functions | Exported SNMP utility functions | Trouble Shooting | Acknowledgements | AUTHOR | Copyright | POD ERRORS

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