<![CDATA[IPv6 outbound SMTP check fails: port25check.cloudron.io refuses connection, Gmail succeeds]]>Cloudron reports IPv6 outbound port 25 as blocked. However, connections to gmail-smtp-in.l.google.com:25 succeed over IPv6 from both the VPS and the mail container.
The configured check endpoint, port25check.cloudron.io (2604:a880:800:10::b66:f001), returns “Connection refused” on port 25.
Could you verify the IPv6 check endpoint?

]]>https://forum.cloudron.io/topic/16157/ipv6-outbound-smtp-check-fails-port25check.cloudron.io-refuses-connection-gmail-succeedsRSS for NodeThu, 05 Nov 2026 13:32:40 GMTMon, 19 Oct 2026 18:21:24 GMT60<![CDATA[Reply to IPv6 outbound SMTP check fails: port25check.cloudron.io refuses connection, Gmail succeeds on Wed, 21 Oct 2026 18:16:01 GMT]]>Thanks, @nebulon! I’ve refreshed the checks and everything is green now. Appreciate the quick fix!

]]>https://forum.cloudron.io/post/131436https://forum.cloudron.io/post/131436Wed, 21 Oct 2026 18:16:01 GMT<![CDATA[Reply to IPv6 outbound SMTP check fails: port25check.cloudron.io refuses connection, Gmail succeeds on Tue, 20 Oct 2026 08:36:13 GMT]]>Good catch! There was some behavior change in nodejs which made the same code stop listening on both ipv4 and ipv6 interfaces on the port check service. This fixed now.

]]>https://forum.cloudron.io/post/131265https://forum.cloudron.io/post/131265Tue, 20 Oct 2026 08:36:13 GMT