df -h   - disk space
iftop  - proces
systemctl restart apache2   - restart
sysctl -p  -  restart /etc/sysctl.conf
 lsof -i -n   -  tcp/udp connect active
 netstat -plant  - 
 netstat -taucp  -
 netstat -t -u  -p   -
 journalctl -xe  -
 netstat -taucp | grep apache2 -
 systemctl list-units --type=service --state=running -
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