SteamCMD fail to download with iptables INPUT DROP

[Nuanda31]

OS Name/Version: Debian 11

Product Name/Version: AMP version 2.6.0.6 - 20241120.1

Problem Description:

In my dedicated server iptables is setup with INPUT DROP.
When the following command “ampinstmgr dumpfirewall” is executed some rules are added to iptables :

15       0     0 ACCEPT     tcp  --  any    any     anywhere             anywhere             tcp dpt:2223 /* AMP:ADS01:FileManagerPlugin.SFTP.SFTPPortNumber */
16       0     0 ACCEPT     udp  --  any    any     anywhere             anywhere             udp dpt:12820 /* AMP:ADS01:ADSModule.Network.MetricsServerPort */
17       0     0 ACCEPT     tcp  --  any    any     anywhere             anywhere             tcp dpt:tproxy /* AMP:ADS01:Core.Webserver.Port */
18       0     0 ACCEPT     tcp  --  any    any     anywhere             anywhere             tcp dpt:2224 /* AMP:NuandaNode01:FileManagerPlugin.SFTP.SFTPPortNumber */
19       0     0 ACCEPT     tcp  --  any    any     anywhere             anywhere             tcp dpt:7777 /* AMP:NuandaNode01:GenericModule.App.Ports.$ApplicationPort1 */
20       0     0 ACCEPT     udp  --  any    any     anywhere             anywhere             udp dpt:7777 /* AMP:NuandaNode01:GenericModule.App.Ports.$ApplicationPort1 */

But when I create an instance for a Steam game the installation or update failed on SteamCMD download. And if I setup iptables INPUT to ACCEPT it works.
Can I find documentations of iptables rules mandatory ?

Steps to reproduce:

• create instance
• choose Steam game
• go to manage

Actions taken to resolve so far:

• execute “ampinstmgr dumpfirewall”

[Greelan]

I doubt the firewall is the real issue here. The default policy for the INPUT chain is drop. All my hosts have it and I don’t have any SteamCMD issues

[Nuanda31]

Thank you for your reply, after some research I found some rules missing in my configuration for established connections.