UNIX for Advanced & Expert Users

is there a way to do this through snmp?

i'm writing a shell script that will be run against several servers, but when i run the script, the most i get back from snmp is information that is simple.

the snmp in the script tells me if the box is linux or solaris. but it doesn't tell me the version number of the OS.

anyone know of a way to get this?

Code:

snmpwalk -v 2c -c bacl@RP blah.net sysDescr 
SNMPv2-MIB::sysDescr.0 = STRING: Linux blah.net 2.6.9-89.ELsmp #1 SMP Mon Apr 20 10:34:33 EDT 2009 i686

I'm missing something - the output you show does have kernel information - essentially the output of uname -a. This tells you a lot. You can teach your code what it means and decode it. How many server nodes in the network? A simple file or db tablewith nodenames, which you have to have anyway, with an extra set of fields can hold this infor.

For Linux & other UNIX, you seem to want the contents of a file like /etc/release, or whatever. The simplest way without writing a bunch of MIB C code is to use a direct ssh connection through a nothing-like account that can only see /etc/release (or whatever you deem necessary). Assuming that a version number is mission critical: Net-SNMP and 'what's up gold' among other snmp software offerings all provide for this - the scripted ssh connection kind of thing. As an example: WUG interfaces with IMacro so you can write expect-like scripts and get anything you want from a system, read-only, provided it doesn't violate security rules.

Also, I do not know of an OID speficied to do that. SysDescr is up to the OS implementer what gets returned AFAIK.

Even in Linux there is no simple approach to getting that information. Some Linux distributions "lie" about their release name. Some use lsb-release. The C code we use to determine OS and release information is a couple of hundred lines of code.

You can try using nmap tool.

In my practice it has show success mostly, but it's not 100%

thank you so much for everyone who has replied. i have one question:

If i run a snmp against a host and i get the following, what can you ascertain about that host:

Code:

Linux 2.6.18-274.7.1.el5 #1 SMP Mon Oct 17 11:57:14 EDT 2011 x86_64

That it is probably Red Hat Enterprise Linux 5 (el5 part in second field).

probably? oh jeez. i'm really hoping i can use snmp for this. but the general consensus that i'm getting here is that it's not reliable?

i assumed it would be a red hat enterprise linux 5.

but i'm curious as to what "2.6.18-274.7.1" means.