From adabc06578edc303eb88928fd1be67848e895bab Mon Sep 17 00:00:00 2001 From: Michael Kuron Date: Sat, 19 Aug 2017 18:06:04 +0200 Subject: [PATCH] Debug: Docker and firewalls --- docs/debug-common_problems.md | 1 + 1 file changed, 1 insertion(+) diff --git a/docs/debug-common_problems.md b/docs/debug-common_problems.md index 095f428c8..fdcb937bb 100644 --- a/docs/debug-common_problems.md +++ b/docs/debug-common_problems.md @@ -56,6 +56,7 @@ while trying to start / install mailcow: dockerized, make sure you've followed o ## XYZ can't connect to ... Please check your local firewall! +Docker and iptables-based firewalls sometimes create conflicting rules, so disable the firewall on your host to determine whether your connection issues are caused by such conflicts. If they are, you need to manually create appropriate rules in your host firewall to permit the necessary connections. If you experience connection problems from home, please check your ISP router's firewall too, some of them block mail traffic on the *SMTP* (587) or *SMTPS* (465) ports. It could also be, that your ISP is blocking the ports for *SUBMISSION* (25).