If the server is running, stop it by pressing Ctrl + C in the terminal (or screen/tmux instance) that the server is attached to. Otherwise, switch to the steam user.
sudo -u steam -i
Login to the Steam account used when installing the server.
Set the Arma 3 installation directory used when installing the server.
Update the Arma 3 Linux server. The validate option will check for corruption.
app_update 233780 validate