Linux sysadmin

[petergriffin]

Ahh yes. I can see the conversation with the pimp now.

"I need someone with Centos or Redhat Enterprise Linux."
"I have Slackware - that's basically the same with a different kernel and config files in different places."
"Ah yes, but they say they want Centos or RHEL. I guess you're not a good fit. Goodbye."

Nothing prevents you from installing Slackware and then installing say, CentOS, on a virtual machine. And nothing prevents you from installing both distros on Windows on a virtual machine. Actually it's a better way of learning Linux. I am very much a fan of Qemu. If you want the Qemu binaries for Windows they're here:
QEMU for Windows
Manual is here:
QEMU Emulator User Documentation

If you really need to go the RHEL route, stick with CentOS. Fedora is pure junk.

I have learnt a lot from the IBM Developer Works site:
IBM developerWorks : Linux

[RasputinDude]

If you really need to go the RHEL route, stick with CentOS Scientific Linux. Fedora and Centos6 are pure junk.

FTFY

[kingcook]

Ultimately, there's no substitute for experience. If you can do most of that already, then you're most of the way there.

After that, I would suggest that most of your issues will be around topology, infrastructure and trying to keep rubbish application suites going. Oh and users, of course. No-one has yet found a way to get rid of the users stuffing things up.

I agree - it's down to experience. I started with Linux (Redhat) around 13 years ago. I've done loads with Linux since then (moved onto Fedora, CentOS, Ubuntu and Debian). Some while a permie, some while pissing around with it at home.

My reason for wanting more knowledge is that it's getting depressing seeing only 1 or 2 Perl developer contracts come up every few months and wanting to get hardcore with something else. Linux seems the best way to go because of all i've learnt with it.

[kingcook]

IMO it would just depend on what you are looking to improve in terms of performance. If your system is running databases and top is showing they are hogging resource then it is that the code is not well optimised, that the database system is not optimised for the hardware or that the hardware is not good enough to meet the demands placed upon it.

As others have said a lot of this comes down to experience, knowing a bit about sysadmin is good, being able to identify if the database queries or the code layer are causing a problem can be worked out a lot of the time by examining slow queries - mtop I find really hand to indentify DB issues. Other times speed of system is simply down to disk IO and the only way to speed up systems is to improve hardware (use of SSD or SAS instead of SATA for example) but it really does depend on what you have running and where you are seeing bottlenecks.

Here are a few bits from my bookmarks:
20 Linux System Monitoring Tools Every SysAdmin Should Know
https://lwn.net/Articles/387202/
Postfix Performance Tuning

From what you have said you can do already you pretty much are a sysadmin. If you want to get work in this field then I guess it is the same as any new skill, blag a lower level position, learn as much as you can and after a year or two go contracting

Cheers for the links, will look into these.

[kingcook]

+1

VM's are your friend if you don't have spare hardware. I now use VM's to clone production systems so any signifcant changes can be tested before deploying on a live server. I also use the same to test new server OS versions, updates / upgrades and just about anything else that might make a performance improvement (other than physical hardware). Love my job as a sysadmin and I learn something new every day.

PS Security is just as important as performance tweaking and that's a whole topic in itself.

VM's are great, I use them only as a dev environment for coding though. Got experience with VMware workstation and server, also VirtualBox and QEMU.

[RasputinDude]

My reason for wanting more knowledge is that it's getting depressing seeing only 1 or 2 Perl developer contracts come up every few months and wanting to get hardcore with something else. Linux seems the best way to go because of all i've learnt with it.

It seems that most of the perl jobs have given way to php. Maybe that could be a way to go? Getting hardcore with the whole LAMP stack seems to offer a lot of possibilities.