[CentOS] Spacewalk or Puppet?

Wed Nov 4 17:05:09 UTC 2009
nate <centos at linuxpowered.net>

Les Mikesell wrote:

> What good is a configuration tool if it can't handle a change in NIC
> setup?  That's really about the only thing that is enough trouble to do
> manually that it is worth more automation than a shell loop of ssh commands.

Just wondering what kind of NIC setup? In the hundreds of systems I
have managed I've never had to change the default NIC settings. If
you mean interface (IP/etc) setup then that could be an issue, for
me I have a script that grabs the MAC addresses and serial numbers
and polls a web server with config files associated with them to
configure interfaces upon system installation (I haven't had to
change them post install, I prefer just to re-install if the system
is being re-purposed).

> Exactly - and remote 'hands on' support generally won't know which NIC
> is which, making this fairly problematic.  And you can't just clone
> setups because the copies won't work with different MAC addresses.

If your setup is simple, e.g. 1 network, what I do is I bond all
of the interfaces into a single bond in active/passive mode, that
makes all of the NICs available for the same purpose, no need to know
what is where. If the system needs to access another part of the
network that is handled via routing not via physical connection.

If you have an issue where you need to change a NIC's duplex
setting because of a flawed switch I'd suggest you look at replacing
your switches(at least going forward). I've only had to screw with
the duplex setting on a couple of occasions about 5-6 years ago
with really old HP big iron. Hundreds of x86 boxes and different
switch types/models/vendors later never had a problem.


> small sets.  Do any of the tools make this easy?  That's the main reason
> I haven't used OCSinventory's deployment mechanism even though its
> cross-platform capabilities are appealing in a mixed environment.

Define easy, in cfengine and puppet(I'm sure, never used it though)
you can define a class of systems and roll the change out to that
class. OCS really is a poor management system IMO, it's ok for
inventory but the rest is crap. Can't speak for spacewalk, it sounds
like a decent inventory/installation system for redhat-based systems
but myself wouldn't use it beyond that role.

My own cfengine configuration consists of roughly 17,000 lines and
a couple thousand files that are pushed out to various systems(in many
cases I push out entire config files rather than having cfengine
edit them inline).

It takes some time to get ramped up(I've been working with
cfengine for many years) but once your there life is a lot
easier. Probably took me a good 2 years of learning. A lot of
it revolving around changing the way you think, how can X concept
be applied in a more generic fashion to dynamically adapt to more
systems automatically for example. Such as defining a dynamic
class so when you build a new server it automatically gets everything
it needs without having to go touch your policy files.

nate