[CentOS] SNMP and OID/MIB/MRTG
bob at bobhoffman.com
Fri Sep 12 02:59:30 UTC 2008
>From what I read in the man pages about snmpwalk....and the snmp.conf file,
I had better take a very long course in configuration of snmp before I
fiddle with it.
At least now I know why there is not 'walk through' online showing you how
to do this...all of them nimbly 'skip' over the whole process of getting the
MIB and just insert this 'mysterious' info into the tutorial...
Gotta love it.
I do promise you all, that I will learn snmp as I think it could be an
important tool for a wsystem admin. Once I get it down, at least the basics,
I will post a very detailed how to on it and hopefully others can use it
without spending months on leanring hardware engineering.
> -----Original Message-----
> From: centos-bounces at centos.org
> [mailto:centos-bounces at centos.org] On Behalf Of Filipe Brandenburger
> Sent: Thursday, September 11, 2008 10:23 PM
> To: CentOS mailing list
> Subject: Re: [CentOS] SNMP and OID/MIB/MRTG
> On Thu, Sep 11, 2008 at 21:46, Bob Hoffman <bob at bobhoffman.com> wrote:
> > Question 1- does snmpd have to run as a daemon, or only run
> once so I
> > can get OID and MIBs from it?
> Yes, it has to be running as a daemon.
> > Question 2- does anyone know the command in snmp to get the
> > OID and MIBs that MRTG needs to use? Or at least the name
> of it? There
> > are a lot of poorly written man pages, but so far all of
> them require
> > an MIB or OID to use the commands I have read.
> Well, the OIDs that you will use on MRTG's config will depend
> on what you want MRTG to trace. Is it the network traffic? Is
> it the disk usage? Is it the CPU usage? Free memory? You can
> get MRTG to trace any of that by using the specific OIDs. You
> can use the "snmpwalk" program to see all the information
> that the daemon will have to offer in order to choose what
> you want to plot.
> > Question 3- since not going outside of the server, is there any
> > security setting in some snmp config file that makes it
> only look on
> > my local server and not allow others to use it or hack it?
> Yes, you can restrict snmpd to answer only to the localhost.
> I suggest you start with a /etc/snmp/snmpd.conf that contains
> this line only:
> rocommunity MySecretString 127.0.0.1
> Replace "MySecretString" with a secret string not known to
> others, this string is what is called "community" in
> snmp-speak. This way, snmpd will answer only to queries made
> from the localhost, and only to someone who knows the right
> "community" secret string (like a password).
> > Question 4- all over the internet there are examples in
> MRTG using all
> > sorts of made up names like 'crazyguy33 at servername' and things like
> > that for the cfg file. And alsoin the snmp forum posts, but no one
> > really talks about where this name comes from other than it is
> > assigned to your network device or something.
> This is probably the community and the host. As I suggested
> restricting to localhost only, you will probably want to use
> something like "MySecretString at localhost", obviously
> replacing "MySecretString"
> with the one you chose.
> The CentOS Wiki also has resources on MRTG, I suggest you
> look there as well:
> CentOS mailing list
> CentOS at centos.org
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