If firewall rules change or reset after reboot, they may be managed by your OS or other services.
Common causes
Default OS firewall policies
Docker modifying firewall rules
Firewall services overriding manual changes
Check your firewall system
Depending on your system, rules may be managed by:
iptables
ufw (Ubuntu)
firewalld (CentOS/RHEL)
Docker related issues
Docker can modify firewall rules automatically.
To disable Docker’s iptables management:
--iptables=false
Note:
This may affect container networking
Use only if you understand the impact
Recommendation
Make firewall rules persistent using your OS firewall tool
Avoid manual changes that get overridden after reboot