[tom_b]

For better or worse, there are employers and fields where obtaining a certification is an important signalling mechanism.

Carefully consider whether or not a Linux administration gig is one of those - I personally don't know. I know in a search for a senior Linux sysadmin at my workplace, certification has not been mentioned at all.

In other areas, particularly high-end customer support gigs in network hardware (e.g., supporting Cisco and/or Juniper gear), certifications like the CCIE are a de-facto requirement for many. Oracle work used to be this way, especially for consultants, but I don't know if that is still true.

In a more general sense, self-study and the time investment in getting certifications has intrinsic worth. Just don't think magically adding a cert tag to your resume will result in a magic increase in professional opportunities and pay.

Work on building your experience portfolio. If you want to use a certification as part of that, I don't think anyone should tell you not to.