SNMP - The Perl5 'SNMP' Extension Module for the Net-SNMP SNMP
package.
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";
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).
$sess = new SNMP::Session(DestHost =>
'host', ...)
The following arguments may be passed to new as a hash.
- 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'.
- 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 either 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 as 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 presented hostname in the certificate
matches.
- 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 format is as a string without the leading '0x'.
So if snmptrapd.conf has "-e
0x8000000001020304", use "SecEngineId
=> '8000000001020304'".
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).
- For SNMPv1 and SNMPv2c, the clear-text community name to use.
The default is 'public'.
- 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.
- $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>, <OPTIONS>)
- 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 for 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.
- $sess->get_sec_engine_id
- Returns the security engine ID for the current session, whether probed or
provided by the client, in hex format suitable for the SecEngineId
parameter when creating a session in the future. Returns undef if we have
not had not had any contact with the remote agent yet.
- $sess->get_context_engine_id
- Like get_sec_engine_id, but for the context engine ID
(ContextEngineId).
$sess = new SNMP::Session(DestHost =>
'host', ...)
supports all applicable fields from SNMP::Session (see above)
- $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
<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.
<callback> may be one of the following forms:
- without
arguments
- 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 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::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
- $SNMP::dump_packet
- default '0', set [non-]zero to independently set
snmp_set_dump_packet()
- SNMP::register_debug_tokens()
- Allows to register one or more debug tokens, just like the -D option of
snmpd. Each debug token enables a group of debug statements. An example:
SNMP::register_debug_tokens("tdomain,netsnmp_unix");
a tied hash to access parsed MIB information. After the MIB has
been loaded this hash allows access to to the parsed in MIB meta-data(the
structure of the MIB (i.e., schema)). The hash returns blessed references to
SNMP::MIB::NODE objects which represent a single MIB attribute. The nodes
can be fetched with multiple 'key' formats - the leaf name (e.g.,sysDescr)
or fully/partially qualified name (e.g., system.sysDescr) or fully qualified
numeric OID. The returned node object supports the following fields:
- objectID
- dotted decimal fully qualified OID
- label
- leaf textual identifier (e.g., 'sysDescr')
- subID
- leaf numeric OID component of objectID (e.g., '1')
- moduleID
- textual identifier for module (e.g., 'RFC1213-MIB')
- parent
- parent node
- children
- array reference of children nodes
- nextNode
- next lexico node (BUG!does not return in lexico order)
- type
- returns application type (see getType for values)
- access
- returns ACCESS (ReadOnly, ReadWrite, WriteOnly, NoAccess, Notify,
Create)
- status
- returns STATUS (Mandatory, Optional, Obsolete, Deprecated)
- syntax
- returns 'textualConvention' if defined else 'type'
- textualConvention
- returns TEXTUAL-CONVENTION
- TCDescription
- returns the TEXTUAL-CONVENTION's DESCRIPTION field.
- units
- returns UNITS
- hint
- returns HINT
- enums
- returns hash ref {tag => num, ...}
- ranges
- returns array ref of hash ref [{low => num, high => num}, ...]
- description
- returns DESCRIPTION ($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
- &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);
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
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.)
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.
bugs, comments, questions to
net-snmp-users@lists.sourceforge.net
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.