Last week I attended the
Red Hat RH300
course (fast track) in Amsterdam and did the RHCSA and RHCE exams on
the final day. I passed both RHCSA (283/300 points) and RHCE (300/300
points). I had a great teacher because, apart from technical stuff, I
also learned how to approach the exams.
The objectives for both
RHCSA and
RHCE
are well documented on Red Hat’s site. You should start to make sure
you know everything inside out. Practise, practise, practise. Learn to
use the documentation that ships with
RHEL,
as this is the only help available: no internet access is provided
during the exam. There are several books available that help prepare and
Red Hat has very good courses as well, that I really recommend. I
assume you should be able to study this all one way or the other.
One advise on this though: don’t try to remember everything but
remember the references instead. If you know a man page has examples you
can use, just remember the man page. If you know documentation is in a
separate package, remember the package name. A references takes less
‘memory’ in your head, so you can remember more. This will speed up your
work significantly.
But wait, technical knowledge is just one challenge. Watch out for the pitfalls:
Pitfall #1: Time
Most experienced Linux sysadmins will probably be able to pass the exam
if there was no restriction on time. You could test, trial-and-error and
read man pages all day long. Even start from scratch when you seriously
broke something. Well, it’s time to wake up: in reality time on the
exam is (very) limited. And yet many candidates do not manage their
limited exam time.
A classic example: spending too much time on something that does not
work right away. Instead, accept the fact it doesn’t work now and
continue with other tasks or else time will run out. When you have given
everything a first attempt, you can always return to a task that you
skipped before.
Not only should you know immediately what to do when you read the
tasks, you need to know the fastest way to configure something. Yes, the
fastest way. Not the way you prefer to do it, or have been
doing it until now. I’ve heard people complaining about the GUI/TUI
tools. And I agree a GUI is not something you want on a server. But hey,
if ‘system-config-authentication‘ has a ready to fill-in form
and makes you configure LDAP with TLS and Kerberos in 60 seconds. Why
would you want to go for the manual way on the exam? Yet, some feel they
are better off configuring this on the command line. There’s simply no
time for that approach, nor will it bring in more points. Be smart, take
the fast track.
Pitfall #2: Your assumptions
Reading is a big problem because candidates tend not do read
very well on the exam. Especially when aware of Pitfall #1, they will
not spend the first few minutes reading instructions. A waste of time,
right? But in reality this will cost precious time later on because
assumptions are made, but never checked. Is it a good idea to start
working on something, without seeing the bigger picture?
I don’t think so. Sometimes, tasks are related but not grouped
together. When you read everything first, you might find that doing two
tasks together is easier. Or you might choose a different approach based
on all information, instead on just a single task. Reading ahead helps
you understand the bigger picture.
Imagine you are asked to configure, let’s say, NTP. Some assume they
have to sync to a time source that is provided and then have to setup a
NTP server and serve time to the local network. But isn’t is a waste of
time to configure a NTP server, when all you have to do is setup a NTP
client? This also occurs with tweaking configurations more than is being
asked for. Keep it simple and do exactly what is asked for.
How I avoided the pitfalls
Value your own work through the eyes of a customer. Example: if a
web server is perfectly configured but a firewall prevents access to it,
then this does not work for a client. Website is down: zero value. Red
Hat might also values your work on the exam like this. Keep that in
mind.
Structure is another important thing to work on. This was my approach on the exam:
1. Imagine you are working for a client
that has written down everything they want from you. Read it all and try
to understand the bigger picture. Then reorganize it: group together
what belongs to each other.
2. Install everything at once. After step 1 you should have identified all packages you need to install. Do it now. Then ‘chkconfig on‘
every service you will configure later. Why? Because it is easy and it
prevents forgetting it later on. Remember: a perfectly configured
service that does not start at boot brings in zero points.
3. Then setup the firewall for the
services you identified at step 1 and installed at step 2. You probably
need to tweak this as you go through the tasks, but just setup the
basics now. This will make it easier later on.
On my exam the first 3 steps took less than 20 minutes and provided a solid base to build on.
4. Work through all tasks and remember: Be
smart, take the fast track. Also, skip any task that you are stuck on
for more than 10 minutes.
Reboot a few times and recheck everything
you have finished so far. Your work is reviewed after a reboot anyway,
so you should make sure your changes survive a reboot. The sooner you
find a problem, the sooner you will be able to solve it.
5. When everything is done, carefully check the items a final time. Then you’re done. And, you probably have some time left!
