I took and passed both Red Hat Certified System Administrator (RHCSA) and Red Hat Certified Engineer (RHCE) exams. The certification is valid for 3 years. After that you have to either retake RHCE exam or pass other higher level Red Hat certification in order to prolong certification validity. RHCSA exam took 2.5 hours and RHCE 2 hours. I was nearly done after 1 hour and used the remaining time for checking.

My tips for examination pass:

• No STRESS. There is no need for it as topics covered in both exams are pretty basic and anyone with Linux systems administration experience will pass it.
• Use GUI tools everytime possible. They save time, which you might need for checking other stuff.
• Reboot the virtual machine at least once to check if every needed service will autostart.

I was told that results would be known in 3 US business days' time. However, I received email with results in several hours after I took the exam and even examiner was suprised how fast the results arrived. The whole process was a very good experience.