SNMP Clients

Command line client applications

To configure SNMP client applications on Debian, including snmpwalk:

apt-get install snmp

If you want to resolve OIDs to their text description, also install snmp-mibs-downloader (non-free repository):

apt-get install snmp-mibs-downloader

Edit /etc/snmp/snmp.conf, and comment the line ‘mibs :’.

If you have a SNMP server on localhost, with Community string ‘public’, you can test this:

% snmpwalk -v1 -cpublic localhost
SNMPv2-MIB::sysDescr.0 = STRING: Linux eedesne 2.6.36 #2 SMP Fri Oct 22 00:03:39 BST 2010 i686
SNMPv2-MIB::sysObjectID.0 = OID: NET-SNMP-MIB::netSnmpAgentOIDs.10
DISMAN-EVENT-MIB::sysUpTimeInstance = Timeticks: (141766) 0:23:37.66
SNMPv2-MIB::sysContact.0 = STRING: Me

SNMP Servers

This is the daemon providing SNMP services. SNMP ‘agents’ run on the server side, which listen for incoming SNMP requests from clients and provides responses. Install this from the snmpd package:

apt-get install snmpd

Edit /etc/snmp/snmpd.conf to configure. A simple test, is to allow access from localhost. To enable this, uncomment the line:

rocommunity public localhost

You can now query your local server using ‘public’ as your Community string as follows:

% snmpwalk -v1 -cpublic localhost

If you have downloaded MIBs (e.g. using snmp-mibs-downloader) I suggest to comment the following line in /etc/default/snmpd:

export MIBS=/usr/share/snmp/mibs

SNMP on Debian – older information

The following section applies to Debian GNU/Linux 3.1 Sarge, and dates from 2005, so may not be relevant any more.

Defaults

Agent

Starts allways by default. Listens on all interfaces, correct by adding the address you want it to listen on in /etc/default/snmpd to the parameter SNMPDOPTS:

change from

SNMPDOPTS=’-Lsd -Lf /dev/null -p /var/run/snmpd.pid’

to

SNMPDOPTS=’-Lsd -Lf /dev/null -p /var/run/snmpd.pid 192.168.123.4′

It also listens to the smux port (199) on all interfaces, which can only be altered to listening only to localhost by recompiling. More on this later. It can be argued, with security in mind, to configure snmpd to listen only on localhost. To make it accessible over the net you would have to add tricks like a tunnel, but that goes beyond the scope of this document. Feel free to add it to this page if you know how to do it.

Trap server

Does not start by default. See /etc/default/snmpd

Note: does not need to run on ervery server, you only need 1 trap server in your network, unless it’s overloaded or for reasons of redundancy or security.

Rebuilding

Needed packages to make building possible:

(install all extra packages with apt-get install packagename)

autoconf
automake1.4
autotools-dev

You need the following extra packages to rebuild snmpd:

libwrap0-dev
libsensors-dev
libssl-dev

Which you can install the easiest (according to http://www.debian.org/doc/manuals/apt-howto/ch-sourcehandling.en.html#6.2) with:

apt-get build-dep package

Download the sources in /usr/src:

user@buildserver:/usr/src >apt-get source libsnmp-base libsnmp5 snmpd
Reading Package Lists… Done
Building Dependency Tree… Done
Need to get 9967kB of source archives.
Get:1 http://d-i stable/main net-snmp 5.1.2-6.1 (dsc) [“1086B”]
Get:2 http://d-i stable/main net-snmp 5.1.2-6.1 (tar) [“3254kB”]
Get:3 http://d-i stable/main net-snmp 5.1.2-6.1 (diff) [67.5kB]
Get:4 http://d-i stable/main net-snmp 5.1.2-6.1 (dsc) [“1086B”]
Get:5 http://d-i stable/main net-snmp 5.1.2-6.1 (tar) [“3254kB”]
Get:6 http://d-i stable/main net-snmp 5.1.2-6.1 (diff) [67.5kB]
Get:7 http://d-i stable/main net-snmp 5.1.2-6.1 (dsc) [“1086B”]
Get:8 http://d-i stable/main net-snmp 5.1.2-6.1 (tar) [“3254kB”]
Get:9 http://d-i stable/main net-snmp 5.1.2-6.1 (diff) [67.5kB]
Fetched 9967kB in 1s (7314kB/s)
dpkg-source: extracting net-snmp in net-snmp-5.1.2
Skipping unpack of already unpacked source in net-snmp-5.1.2
Skipping unpack of already unpacked source in net-snmp-5.1.2
user@buildserver:/usr/src >

results in :

user@buildserver:/usr/src >ls -al||grep snmp
drwxrwxr-x 15 user src 4096 2005-08-24 10:42 net-snmp-5.1.2
-rw-r–r– 1 user src 67522 2005-03-31 17:32 net-snmp_5.1.2-6.1.diff.gz
-rw-r–r– 1 user src 1086 2005-03-31 17:32 net-snmp_5.1.2-6.1.dsc
-rw-r–r– 1 user src 3253579 2004-08-10 12:32 net-snmp_5.1.2.orig.tar.gz
user@buildserver:/usr/src >

Rebuild to check your environment :

user@buildserver:/usr/src >cd net-snmp-5.1.2
user@buildserver:/usr/src/net-snmp-5.1.2 >debian/rules binary

Yada, yada, yada …

Use of uninitialized value in scalar assignment at /usr/bin/dh_shlibdeps line 13 8.
dh_gencontrol -a
dh_md5sums -a
dh_builddeb -a
dpkg-deb: building package `snmpd’ in `../snmpd_5.1.2-6.1_i386.deb’.
dpkg-deb: building package `snmp’ in `../snmp_5.1.2-6.1_i386.deb’.
dpkg-deb: building package `libsnmp5′ in `../libsnmp5_5.1.2-6.1_i386.deb’.
dpkg-deb: building package `libsnmp5-dev’ in `../libsnmp5-dev_5.1.2-6.1_i386.deb ‘.
dpkg-deb: building package `libsnmp-perl’ in `../libsnmp-perl_5.1.2-6.1_i386.deb ‘.
user@buildserver:/usr/src/net-snmp-5.1.2 >
user@buildserver:/usr/src/net-snmp-5.1.2 >date
Wed Aug 24 10:59:16 CEST 2005
user@buildserver:/usr/src/net-snmp-5.1.2 >ls -al .. || grep ’08-24 10:5’
drwxrwsr-x 10 user src 4096 2005-08-24 10:53 .
-rw-r–r– 1 user src 1533904 2005-08-24 10:53 libsnmp5_5.1.2-6.1_i386.deb
-rw-r–r– 1 user src 1100654 2005-08-24 10:53 libsnmp5-dev_5.1.2-6.1_i386.deb
-rw-r–r– 1 user src 1004758 2005-08-24 10:53 libsnmp-base_5.1.2-6.1_all.deb
-rw-r–r– 1 user src 808572 2005-08-24 10:53 libsnmp-perl_5.1.2-6.1_i386.deb
drwxrwxr-x 15 user src 4096 2005-08-24 10:53 net-snmp-5.1.2
-rw-r–r– 1 user src 811612 2005-08-24 10:53 snmp_5.1.2-6.1_i386.deb
-rw-r–r– 1 user src 730488 2005-08-24 10:53 snmpd_5.1.2-6.1_i386.deb
-rw-r–r– 1 user src 754554 2005-08-24 10:53 tkmib_5.1.2-6.1_all.deb
user@buildserver:/usr/src/net-snmp-5.1.2 >

[Todo : Find out why building from sources libsnmp-base, libsnmp5 and snmpd produces packages libsnmp5, libsnmp5-dev, libsnmp-base, libsnmp-perl, snmp, snmpd & tkmib]

Using your own packages

Since I prefer installing packages automatically using the same means as the original install method, I’m describing my own way through a debian-local directory on my local web server in combination with apt-proxy. Feel free to install your packages with

dpkg -i ./packagefile.deb

if you feel an urgent need to create work or for testing purposes.

So I run a local apt-proxy which keeps a copy of my downloaded packages on my local web server and have a real (so not proxied) local directory that’s part of my /etc/apt/sources.list (the place apt uses to install new packages and updates over the net) in which I store my home-grown packages:

deb http://d-i.local/debian sarge main contrib non-free # proxied
deb-src http://d-i.local/debian sarge main contrib non-free
deb http://d-i.local/debian-security sarge/updates main contrib non-free
deb-src http://d-i.local/debian-security sarge/updates main contrib non-free
deb http://d-i.local/debian-local

source http://wiki.debian.org/SNMP

About ngengeh

Nama gw ndry

Posted on April 13, 2012, in Belajar, Linux. Bookmark the permalink. Leave a comment.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: