Administering new server, need help with updates and best practices
 

I've been maintaining a few servers running Ubuntu or some other variant of Debian for a while, but I've just been handed a hosted server running Red Hat, and been told that I need to keep the OS side of things up-to-date.

I'm not really sure where to start with this as I have absolutely no RHEL experience.

# cat /proc/version

returns:

Linux version 2.6.18-028stab070.14 (root@rhel5-build-x64) (gcc version 4.1.2 20080704 (Red Hat 4.1.2-46)) #1 SMP Thu Nov 18 16:04:02 MSK 2010

The server is used as a web server with a handful of virtual hosts, and is running plesk.

Is there any resource I can use to quickly get me up to speed on how to best administer this server?

What are best practices for this server for applying updates?

Moving from a mostly debian based experience, what should I know about Red Hat?

Well first off ... RedHat is better! Ok, maybe thats an opinion but still.

There isn't a whole lot of difference, you will use the yum package manager for updates as opposed to aptitude.

The thing to remember about RHEL is it is a subscription based distro, you have to make sure your systems get registered with the red hat network or yum updates wont work.

a rhn_check command will verify that it can check in to the rhn server. This is one of those gotchas, if it doesnt check in for a long period of time it wont be able to update and you have to run a rhn_register again to re-register it with RHN.


Do you have any other red hat products available? Specifically Red Hat Satellite? That will be a big plus for patching and package management.

Oh and read up on teh Plesk backup features. Since everything is being managed through Plesk make sure you are backing up your Plesk config and your site content through the Plesk control panel atleast once a week and before attempting any Plesk upgrade.

You can use
to find out what version of RHEL you have.
By the look of the date in the version info, its quite old; may even be a v5.x, which is still supported by RH. v5.9 is just out recently.
You'll need to do a comprehensive backup before using yum to update it. It'll require a reboot as it'll have new kernel versions.
(Current latest & greatest is 6.3)

You can check the repo settings by looking in /etc/yum.repos.d dir.

Here are the Admin Guides http://www.linuxtopia.org/online_boo...ion_index.html

As mentioned above, RHEL is a paid subscription distro, so contact RH and/or your Mgr to get the subscription info, otherwise no updates or support will be forthcoming.

Ultimately if money becomes an issue, you could convert it to Centos, a free RHEL rebuild, but that only includes updates.
You'd have to support it yourself via Google, LQ, the Centos website etc.

HTH

Thanks guys, I'll run with that!

[edit]

cat /etc/redhat-release gives me "CentOS release 5.7 (Final)", so I guess we're actually on the CentOS train, which probably explains why rhn_check gives me command not found.

Yep, rhn commands aren't going to work as there is no support subscription here. As previously stated there is no difference between RHEL and CentOS with the exception of the subscription support and supplementary products you can purchase such as Satellite.


On chrism01's suggestion on the upgrade; I do recommend staying on the most up to date as well but there are significant changes from the RedHat 5.x family to the RedHat 6.x family. 5.x is still well within support and will be for quite some time, no need to upgrade unless you want to at this point. Review the release notes and make the decision as to whether it is the right thing to do for your environment.

I've decided to shoot myself in a virtual foot before tackling anything on the production server. I've setup a VM and installed the same version of CentOS, and am now slowly looking at getting Plesk installed. I figure I can then test restoring the backup of the production server to my VM and play with that a bit.

With the Plesk backup features it should be an easy restore, just keep in mind that it will restore all your IP and network bindings so the VM may try and steal your production IPs if you have it on the network.

Sure, having to search for distribution-specific commands (like RPM* or Yum*) may be disorienting for a minute but what any Linux distribution has in common is that conceptually things like server maintenance and security issues don't differ. What Debian and RHEL have in common too is they both come with extensive documentation you can consult.

Using a virtual machine is a good move but IMNSHO the best way to fsck up right from the start is to let another layer of "just click OK button" obfuscation get between the OS and person supposed to gain practical experience from using it.

*BTW CentOS 5 is at 5.9 now so the machine is two updates behind.

Well, now you know what you've got and that its a couple of minor versions behind.
Taking a copy and playing with it is a good idea, but watch for hostname/ips as warned above.
The link I gave you will be fine for the manuals. Note that since its a rebuild, RHEL manuals are the same as the Centos manuals (excepting rhn related of course).

Personally I'd recommend trying to learn how to manage from the cli rather than relying on Plesk if you can.