- RedHat certification - powerful brandname but really expensive certification; about $7000.
- Linux Professional Institute (LPI) certification - vendor independent and about $400 per certification level, see below.
Now, there are 3 Linux certification levels available from LPI: Junior, Advanced and Senior (see here) and the first one was available also through CompTIA that is offering it under the name: "CompTIA Linux+ powered by LPI".
I have chosen the CompTIA one, but it seems it is completely equivalent to the LPI one (and even more; see Greg Porter's very instructive blog).
The overall impression is that this is not a Junior exam at all, in my view.
You can take probably any Senior Linux professional and test him (unprepared) for this exam and he'll probably fail.
Is not the depth of the exam but the diversity of topics and the fact that one can work 24x7 in Linux for 10 years in a row and never encounter some topics covered by this exam. Probably the most obvious one: why did they include SQL in a linux certification at all?
In the same idea, the exam covers the two main distributions on the market (Debian and RedHat and their derivatives) and if you're specialized for years on one side there is a slim chance you know or even care about the other side.
Finally, the exam takes into consideration different versions of the same applications (e.g. XFree86 3.3.6, XFree86 4.x and X.org-X11) and one should remember their quirks, and their similar & different options. In real life this not quite happening and is not very useful; the trend is to unify your systems as much as possible. Then, once upgraded, the system administrator embraces the new set of parameters and throws the old set into gradual oblivion. Some companies even have different admins for different Linux distros, if they were unable to migrate to one system or another.
Anyway, there was a lot of interesting information and enjoyed it a lot. However I have encountered some annoyances and they are all here. Also I have to bark about Pearson Vue mega-corporation. But this, in its own space, i.e. here. M-ha-ha. M-ha-ha-ha!