What is the preffered method of making changes to large numbers of Linux servers?

What is the best method or tool to make identical changes to large
groups of Linux machines?

All of my RH servers are using local /etc/passwd files, no NIS+ or
LDAP yet.

I need to make changes such as updating resolv.conf.

Also doing things like running the same command on every machine, such
as sending me the output of a rpm -qa |grep something.

Thanks in advance!

(E-Mail Removed) (Linux Idiot) writes:

> What is the best method or tool to make identical changes to large
> groups of Linux machines?
>
> All of my RH servers are using local /etc/passwd files, no NIS+ or
> LDAP yet.
>
> I need to make changes such as updating resolv.conf.
>
> Also doing things like running the same command on every machine, such
> as sending me the output of a rpm -qa |grep something.

cfengine.

see: <http://www.iu.hio.no/cfengine/>
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