Last night my OMV was not accessible anymore. Also docker not. I tried to open my web gui, but it responded very slow. After tipying my password and hitting login, I saw firefox was sending and waiting for a lot requests (little notice at the bottom of firefox). I checked the cpu, io and ram usage, but nothing was suspicious. When I tried to login via ssh, I barely could type any letter. After typing two letters into the ssh terminal, I had to wait long time till the next two would appear.
I could not find anything leaking in kernel log. What could explain the slow response from omv nginx? What could explain the extreme delay in which the letters appeared in ssh terminal? Today everything seems back to normal.
How could I check if my server was hacked?