The server has 4 cores and 8 GB RAM, about 10 Joomla sites, different versions, 3-4 of them with lscache plugins. PowerDNS, Postfix, FTP, CSF and modsecurity are enabled.
After sometime OLS is not accessible at 7080 port. I can access CP on 8090 and restart it, so it is functional again.
I already opened 7080 port in CSF and it is accessible (for some time).
It was the first thing I did during setup. It is needed (for me) for (1) learning (2) fine-tuning (3) detailed inspection of connections during testing. I may close it afterwards. CP does not replicate OLS panel (it shouldn’t).
The problem is: it becomes inaccessible after some time - a rather random period.
I read about “number of open files” problem in multiple places, did some touches but I don’t know what to look to debug.