Fetch SNMP object subtree

- « SNMP::setSecurity

- SNMPException »

- PHP Manual
- SNMP
- Fetch SNMP object subtree

# SNMP::walk

(PHP 5 >= 5.4.0, PHP 7, PHP 8)

SNMP::walk — Fetch SNMP object subtree

### Description

public SNMP::walk(
array|string `$objectId`,
bool `$suffixAsKey` = `false`,
int `$maxRepetitions` = -1,
int `$nonRepeaters` = -1
): array|false

SNMP::walk() is used to read SNMP subtree rooted at specified `objectId`.

### Parameters

`objectId`

  Root of subtree to be fetched

`suffixAsKey`

  By default full OID notation is used for keys in output array. If set to `true` subtree prefix will be removed from keys leaving only suffix of object_id.

`nonRepeaters`

  This specifies the number of supplied variables that should not be iterated over. The default is to use this value from SNMP object.

`maxRepetitions`

  This specifies the maximum number of iterations over the repeating variables. The default is to use this value from SNMP object.

### Return Values

Returns an associative array of the SNMP object ids and their values on success or `false` on error. When a SNMP error occures SNMP::getErrno() and SNMP::getError() can be used for retrieving error number (specific to SNMP extension, see class constants) and error message respectively.

### Errors/Exceptions

This method does not throw any exceptions by default. To enable throwing an SNMPException exception when some of library errors occur the SNMP class parameter `exceptions_enabled` should be set to a corresponding value. See `SNMP::$exceptions_enabled` explanation for more details.

### Examples

Example #1 SNMP::walk() example

    <?php
      $session = new SNMP(SNMP::VERSION_1, "127.0.0.1", "public");
      $fulltree = $session->walk(".");
      print_r($fulltree);
      $session->close();
    ?>

The above example will output something similar to:

    Array
    (
        [SNMPv2-MIB::sysDescr.0] => STRING: Test server
        [SNMPv2-MIB::sysObjectID.0] => OID: NET-SNMP-MIB::netSnmpAgentOIDs.8
        [DISMAN-EVENT-MIB::sysUpTimeInstance] => Timeticks: (1150681750) 133 days, 4:20:17.50
        [SNMPv2-MIB::sysContact.0] => STRING: Nobody
        [SNMPv2-MIB::sysName.0] => STRING: server.localdomain
        ...
    )

Example #2 `suffixAsKey` example

`suffixAsKey` may be used when merging multiple SNMP subtrees into one. This example maps interface names to their type.

    <?php
      $session = new SNMP(SNMP::VERSION_1, "127.0.0.1", "public");
      $session->valueretrieval = SNMP_VALUE_PLAIN;
      $ifDescr = $session->walk(".1.3.6.1.2.1.2.2.1.2", TRUE);
      $session->valueretrieval = SNMP_VALUE_LIBRARY;
      $ifType = $session->walk(".1.3.6.1.2.1.2.2.1.3", TRUE);
      print_r($ifDescr);
      print_r($ifType);
      $result = array();
      foreach($ifDescr as $i => $n) {
        $result[$n] = $ifType[$i];
      }
      print_r($result);
    ?>

The above example will output something similar to:

    Array
    (
        [1] => igb0
        [2] => igb1
        [3] => ipfw0
        [4] => lo0
        [5] => lagg0
    )
    Array
    (
        [1] => INTEGER: ieee8023adLag(161)
        [2] => INTEGER: ieee8023adLag(161)
        [3] => INTEGER: ethernetCsmacd(6)
        [4] => INTEGER: softwareLoopback(24)
        [5] => INTEGER: ethernetCsmacd(6)
    )
    Array
    (
        [igb0] => INTEGER: ieee8023adLag(161)
        [igb1] => INTEGER: ieee8023adLag(161)
        [ipfw0] => INTEGER: ethernetCsmacd(6)
        [lo0] => INTEGER: softwareLoopback(24)
        [lagg0] => INTEGER: ethernetCsmacd(6)
    )

### See Also

- SNMP::getErrno() - Get last error code
- SNMP::getError() - Get last error message