Set Permanently ulimit -n / open files in ubuntu

set ulimit

# available limit
user@ubuntu:~$ ulimit -n
1024

# To increase the available limit to say 65535
user@ubuntu:~$ sudo vim /etc/sysctl.conf

# add the following line to it
fs.file-max = 65535

sudo vim /etc/security/limits.conf

# add following lines to it
* soft     nproc          65535    
* hard     nproc          65535   
* soft     nofile         65535   
* hard     nofile         65535
root soft     nproc          65535    
root hard     nproc          65535   
root soft     nofile         65535   
root hard     nofile         65535

# edit the following file
user@ubuntu:~$ sudo vim /etc/pam.d/common-session

# add this line to it
session required pam_limits.so

# run this to refresh with new config
user@ubuntu:~$ sudo sysctl -p

# logout and login and try the following command
user@ubuntu:~$ ulimit -n
65535

doesn't seem to work anymore on ubuntu 21.04

This doesn't work on ubuntu 20.04 LST too

This is not working on Ubuntu 20.04 LTS

it's working on Ubuntu 22.04 LTS

logout and login

did the trick