Once I noticed a message in /var/log/samba/log on one of the servers with samba:
../source3/param/loadparm.c:320(max_open_files)
rlimit_max: increasing rlimit_max (1024) to minimum Windows limit (16384)
The warning is displayed due to the fact that Linux has a default limit of 1024 simultaneously open files, and on Windows it is 16384.
Therefore, we will increase the limit in Linux to 16384:
sudo ulimit -n 16384
Check:
ulimit -Hn -Sn
To prevent changes from being reset after a system reboot, open the file in a text editor:
sudo nano /etc/security/limits.conf
And add at the end:
* - nofile 16384
root - nofile 16384
Done.
See also my article:
How to change “open files” in Linux
sudo: ulimit: command not found
and even:
sudo: unlimit: command not found