Hi everyone, this is my first question. I have successfully configured a stunnel (A) that does the job of it. I need to configure a second stunnel (B) that works in a more hidden network. When B connects to A, which connects to public mail server X I get a time out error.

I bring you the logs, I think it is related to the fact that both stunnel servers are trying to establish a TLS session. Is there a way to solve?

2023.11.02 08:42:10 LOG7[0]: Option TCP_NODELAY set on local socket 2023.11.02 08:42:10 LOG5[0]: Service [smtp-tls] accepted connection from 192.168.0.109:46078 2023.11.02 08:42:10 LOG6[0]: s_connect: connecting 192.168.180.10:25 2023.11.02 08:42:10 LOG7[0]: s_connect: s_poll_wait 192.168.180.10:25: waiting 10 seconds 2023.11.02 08:42:10 LOG7[0]: FD=6 events=0x2001 revents=0x0 2023.11.02 08:42:10 LOG7[0]: FD=11 events=0x2005 revents=0x0 2023.11.02 08:42:10 LOG5[0]: s_connect: connected 192.168.180.10:25 2023.11.02 08:42:10 LOG5[0]: Service [smtp-tls] connected remote server from 192.168.0.23:41156 2023.11.02 08:42:10 LOG7[0]: Setting remote socket options (FD=11) 2023.11.02 08:42:10 LOG7[0]: Option TCP_NODELAY set on remote socket 2023.11.02 08:42:10 LOG7[0]: Remote descriptor (FD=11) initialized 2023.11.02 08:42:10 LOG7[0]: <- 220 mailservers 2023.11.02 08:42:10 LOG7[0]: -> 220 mailservers 2023.11.02 08:42:10 LOG7[0]: -> EHLO localhost 2023.11.02 08:42:11 LOG7[0]: <- 250-email-smtp.posta 2023.11.02 08:42:11 LOG7[0]: <- 250-8BITMIME 2023.11.02 08:42:11 LOG7[0]: <- 250-STARTTLS 2023.11.02 08:42:11 LOG7[0]: <- 250-AUTH PLAIN LOGIN 2023.11.02 08:42:11 LOG7[0]: <- 250 Ok 2023.11.02 08:42:11 LOG7[0]: -> STARTTLS 2023.11.02 08:42:11 LOG7[0]: <- 503 TLS not available due to temporary reason: TLS already active 2023.11.02 08:42:11 LOG3[0]: Remote server is not RFC 2487 compliant 2023.11.02 08:42:11 LOG5[0]: Connection reset: 0 byte(s) sent to TLS, 0 byte(s) sent to socket