My Experience with RHCSA and RHCE

So, I've recently completed the RHCSA and RHCE exams successfully and I wanted to share my experience with it. Here are a few of my thoughts about both exams.

Time:
There's plenty of it on RHCSA but not so much on RHCE. If you know what you are doing on the topics, you'll be done in under 1 hour (in case of the RHCSA) assuming you are decently fast in typing. However, that's not the case with RHCE. For passing RHCE, you'll need to have good time management and eventually skip tasks that you get stuck on since you might not be completing the rest of the tasks.

Tasks:
Take a minute and read through all the tasks first. Map your own 'Big Picture' on how the system has to look like in the end. This includes the configuration of SELinux, Firewalld and systemctl.
Note that your changes and configurations have to be persistent between reboots.
If you can do the labs without too much of a hassle, you should be good to go. What you want to avoid however is rebuilding your machine because you broke it by working on, let's say, partitioning. So, do (potential) destructive Tasks first!

Authentication:
It's generally not a bad idea to generate an ssh-key pair and enable key authentication on the machines you are working on. This saves the time of typing in the password every time you connect using ssh. This might not be that much important in case of the RHCSA-Exam but in the RHCE-Exam every bit of time saved is valuable.

Working with networked Storage:
If you are required to work with iSCSI and/or NFS, always remember the '_netdev' option in your mount options. By forgetting this option, you might look at a machine that takes forever to boot or might not even boot at all since your machine will think it's local storage and mount it before the network stack is started. Worst case is, that you'll be awarded 0 points because your machine isn't booting.

Troubleshooting SELinux:
The best way to troubleshoot SELinux is probably by using the sealert command. This will give you quite a lot of information on what is going on and why something is blocked or denied access to.

Finding help in the exam:
With the RHCSA-Exam I've found every bit of information I needed by adding a simple '--help | less' to my commands. With the RHCE there were man pages that had all the required pieces of information I needed. If you don't know the exact name, try the following command and you should receive a number of man pages associated with your search, here an example with nmcli:

 $ apropos nmcli  
 nmcli (1)      - command-line tool for controlling NetworkManager  
 nmcli-examples (7)  - usage examples of nmcli

Conclusion:
I think the Red Hat Certifications are challenging but they're worth it in the end. You're required to do real world tasks and you'll get rated on how well you did on each task. You're not locked in to a specific set of commands on how to accomplish one specific task but have the freedom to decide how you want to get things done.

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