I wanted to ask people in this community about administration of the Debian based web server - its a dedicated server, hosting a single website.
From time to time the web site is slowing down, on some occasions becoming unresponsive for a half-minute-few minutes period. The causes are always different, so I am fixing one thing - another thing goes wrong, and its getting weird trying to find all the wrong things one after another.
I want to have a way to track down all of the processes related to the web server - apache, nginx, mysql, php, whatever else. I guess I want to be able to understand what happens and why whatever is happening occurs - what causes the slow and etc. So, I am thinking up about the ways to track it all down.
So far, I have the following command to track running apache and nginx processes:
top -u www-data
I have found a way to join "tail" from several log files at once:
tail -f error_log1 -f error_log2
What I need is to find more instruments and the way to track errors better than just looking around logs. Could you suggest me detailed answers on what I can use?
Thanks in advance!