(PHP 4, PHP 5)
snmpwalk — 从代理返回所有的 SNMP 对象
$hostname
, string $community
, string $object_id
[, int $timeout
[, int $retries
]] )
返回由 object_id 作为根的
SNMP 对象值所组成的数组，错误则返回 FALSE。
snmpwalk() 函数是用来读取所有由
hostname 指定的 SNMP
代理的值。Community
指定该代理中具有读权限的域。一个为 NULL
的 object_id 将被看作
SNMP 对象树的根，而在此树下的所有对象将作为一个数组被返回。如果指定了
object_id，则返回所有在
object_id 下的 SNMP 对象。
<?php
$a = snmpwalk("127.0.0.1", "public", "");
?>
上边的函数调用将从运行于本机的 SNMP 代理那里返回所有的 SNMP 对象。可使用循环遍历这些值。
<?php
foreach ($a as $val) {
echo "$val\n";
}
?>
http://mike.eire.ca (2005-03-23 10:54:45)
I found on Windows (PHP 5) an empty string did not return anything, it just timed out. I had to use null instead:
<?php
$a = snmpwalk("127.0.0.1", "public", null);
?>
bobby [dot] clark [at] eku [dot] edu (2003-09-17 14:29:02)
I had to use an object_id like these.
'SNMPv2-MIB::system.sysDescr.0'
'IF-MIB::interfaces.ifTable.ifEntry.ifAdminStatus'
<?php
$host = '192.168.1.1';
$community = 'public';
$object_id = 'IF-MIB::interfaces.ifTables.ifEntry.ifAdminStatus';
$sysdesc = snmpwalk($host, $community', $object_id);
print_r($sysdesc);
?>
Lars Troen (2003-03-14 03:18:46)
Note that there's different behaviuor in php snmpwalk and ucd snmpwalk. If you try to walk an oid that has one value not under a subkey of the walked oid, ucd snmpwalk will return the value while php's snmpwalk will not.
anders at ei dot nu (2003-01-29 10:11:47)
It would be nice to be able to specify what snmp version to use ( 1,2c,3 )
For now, I'ts hardcoded in ext/snmp/snmp.c
change session.version from 1 to 2c or 3 if you need for now..
i.e
session.version = SNMP_VERSION_1;
to:
session.version = SNMP_VERSION_2c;
steve at ourabode dot org (2002-03-26 03:54:30)
Timeout is in MICRO seconds.
1,000,000 µs = 1 s
layer2 at www dot com (2001-08-29 08:52:21)
Something to care about in dealing with snmpwalk:<BR>
While walking the MIB, snmpwalk puts info that gets into an array, and that is correct.<BR>
The trouble happened when snmpwalk needs to collect information from instances that contains subinstances (i.e. walking .1.2.3.4.5 and having instances like 1.1, 1.2, 1.3): in this case it gets info and passes into an array, but when walking the array, each value is preceeded by 'Counter32: '.<BR>
I've tested this in many ways and it always happened the same way.
john at antefacto dot com (2001-08-17 08:21:05)
Ah. That's why all of our SNMP stuff was timing out anytime there was any load on the system. Sigh. A waste of two weeks trying to debug snmp....
Even the snmpcmd manpage doesn't give a
unit for timeout.
billf at freebsd dot org (2001-08-01 02:22:21)
for the poster wondering what the
timeout field was measured in:
from the ucd-snmp header file snmp_api.h:
long timeout;
/* Number of uS until first timeout
then exponential backoff */
jmartinson(AT_nospam)info234.com (2001-06-20 07:41:26)
A quick router device view:
<?
include "header.html";
$host = "auscr1";
$community = "tellme";
$sysDescr = snmpget("$host","$community","system.sysDescr.0");
$ifDescr = snmpwalk("$host","$community","interfaces.ifTable.ifEntry.ifDescr");
$ifIndex = snmpwalk("$host","$community","interfaces.ifTable.ifEntry.ifIndex");
$ifAdminStatus = snmpwalk("$host","$community","interfaces.ifTable.ifEntry.ifAdminStatus");
$ifOperStatus = snmpwalk("$host","$community","interfaces.ifTable.ifEntry.ifOperStatus");
$ifLastChange = snmpwalk("$host","$community","interfaces.ifTable.ifEntry.ifLastChange");
print "<table border=1 bgcolor=#ffffff><tr><td>$host</td></tr></table><br>";
print "<table border=1 bgcolor=#ffffff><tr><td>$sysDescr</td></tr></table><br>";
print "<table border=1 bgcolor=#ffffff>";
print "<tr>
<td>ifIndex</td>
<td>ifDescr</td>
<td>ifAdminStatus</td>
<td>ifOperStatus</td>
<td>ifLastChange</td>
</tr>";
for ($i=0; $i<count($ifIndex); $i++) {
print "<tr>";
print "<td>$ifIndex[$i]</td>";
print "<td>$ifDescr[$i]</td>";
print "<td>$ifAdminStatus[$i]</td>";
print "<td>$ifOperStatus[$i]</td>";
print "<td>$ifLastChange[$i]</td>";
print "</tr>";
}
print "</table>";
?>