Regarding classes, how much experience do you have with Linux in general and the distribution that you use in your office? If starting from utter zero, I'd say begin with something like the very lowest level Red Hat course (033 IIRC). Note that you can learn quite a lot yourself from books and self study, but if you go that route, don't turn the production systems into your personal testing playground -- establish your own test bed on your workstation or a spare machine. Fortunately, the wide availabiltiy of free virtualization software makes this very easily. Speaking of books, I'd recommend taking a long look through this classic
Along with all the essential advice mentioned above, gather the following information about your site. For each computer at your site, maintain documenation such as the following:
- Computer name.
- IP address.
- Operating system and release level.
- Internally available services.
- Externally available services.
- List of users or groups permitted to login to the system.
- List of users or groups (including yourself) that have superuser privilege.
More general site-wide policies that should be documented:
- Is there a central directory service (NIS, LDAP, AD, etc.) for user accounts, or are accounts provisioned on an ad-hoc basis?
- How many users are there, total?
- Is there any configuration management (e.g. Puppet, CFEngine, Chef) deployed? Are there SOPs for deploying new machines?
- Likewise do you have monitoring software (e.g. Nagios) that can notify you if something goes wrong?
- Are there any other company regulations or laws/policies/regulations (such as PCI-DSS. SOX, HIPPA, etc.) that apply to your situation? If so, are you in compliance? How will you make sure you stay in compliance?
Finally, don't neglect security! Make sure you review the CERT checklist for Unix security and other trusted resources. I believe that if you mosey over to the security forum here at LQ, there's a sticky of resources put together by the real experts on this topic. I'd prepare to spend some serious time reading through them.
Finally, good luck. Don't worry about certs etc. I've been a professional sysadmin (as defined as someone else pays me to manage computer systems) for around a decade now and have never bothered to pick up a cert. Certs have their place in the world, but I don't think they're particularly necessary. That being said, if your company provides reimbursment for training expenses or will pay you to be certified, picking up a Red Hat or LPI cert probably wouldn't be a bad thing.