It is time to troubleshooting. It can be challenge once you see a black screen. Especially, a problem on a storage, server that has virtual servers may be painful. If you have a good backup system, you are in safe. I think I had a physical problem on my server. It could not start properly so that there was not any display, below.
I also used ILO console to access to my server as well, below.
I have read some posts about what type of problem can be. Three of them are below.
1. Power supply
2. Main board
3. CMOS battery
First 2 options are really headache. However, last one, CMOS battery problem seems to be a usual suspect, since the server was not able to enter BIOS section.
I tested both power supply one by one, and swaped. Next time, I should follow this boot order that is an example for Linux server to find the root cause. I think it was stuck in POST section.
There are some information on the server front panel.
Best option is to replace this battery with a new one, below.
This battery, left side, was taken out from its motherboard. I think it is over, below. I integrated a new one, right below.
And, the result can be seen below.
Finally, I reached an outcome. However, I should configure its ILO port for the server management section that allows to use virtual drive, turn on/off the server remotely because of the new battery. In addition, I should pay attention on the backup system. If there is a good backup system, no need to worry about data that on the server.
I should edit this post, since the problem was occurred again. After taking out main components from the server such as CPU, ram, power supply, I noticed that the problem was on the ram section. Having organized ram slots, it started without any problem. The solution is to take out main components and take in them again. It helps to detect which component is problematic. When adding new ram, pay attention on the slot order, compatibility such as frequency. If your server is not booting, at first check the ram section, since operating system can not be deployed or fetched. I hope this is informative for you.