What can be the best cert or knowledge combination for Linux Administrator:

Example:

RHCE + CCNA

RHCE + ORACLE DBA

RHCE + VMWARE

RHCE + SQL DBA

That would vary depending on what the duties were.

In most organizations I've been in the System Admin and the DBA are different roles so I probably wouldn't bother with MySQL or Oracle. Similarly usually the networking folks are separate. VMWare on the other hand is used for virtualization in many shops so I'd think a combination of RHCE and VMWare would be good.

Of course certifications help but all by themselves they aren't going to get you a job. Most employers look for experience and will usually higher an experienced admin with no certifications over an inexperienced ones with dozens of certifications.

The more certs the better , I would say the CCNA has gotten me in the door many times over the Redhat cert. I also agree with the previous post that the redhat and virtualization certs go together like ham and burger

I've been working in IT for about 10 years now - started off with Windows and ended up doing Unix based support specifically AIX for the last 6 years. For me what really helped in terms of IT certifications is the core ones like networking and of course some hands on.

I achieved my CCNA last year and that was a huge boost to my career as it added to my day to day admin duties. Since I have to struggle with AIX on a day to day basis I did some IBM courses (paid for by work) to get the training. Right now I am studying for the LPIC 1 & 2 as it covers multiple and differing Linux distros which makes it a good choice. In addition to our IT shop having AIX we have RHEL and now Ubuntu LTS.

RHEL cert is nice but expensive. In my honest opinion you could go for the LPIC which shows the depth of your knowledge over multiple distros and you would still be recognized by your employer for having those skills and the ability to support them no matter what type of Linux comes into your datacenter.

I hold certs from Microsoft and Cisco and am currently working on my LPIC.

Hope this helps!

Most employers want experience in what they do. If they're using RHEL and you have 5 years experience on Ubuntu and LPIC you may not even get an interview. On the flip side you might have 5 years experience on RHEL and your RCHE and not get an interview at a place that uses SuSE.

Remember that headhunters and HR folks do the initial sorting of resumes and they often know almost nothing of what a job requires so do their best to stick to the requirements the hiring manager gave them. Hiring managers usually give wish lists to HR and head-hunters so they often don't even know who has applied.

I once got a job because I'd worked on a specific Sun class of server. A person I knew with more Solaris experience couldn't even get an interview because she hadn't worked on that particular class of server.