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General Discussion / smtp port forwarding
« on: May 13, 2019, 02:53:09 pm »
Hi opnsense users
After testing several firewalls to incorporate into a production environment. I finally chose opnsense, but now I have been having a problem for a few days and I can not find the solution.
I would appreciate if someone can help me solve it.
The problem is:
I have a mail server behind OPNsense 19.1.4-i386, I have configured nat forwarding in 993,465, 587,.. and 25 ports, and everything works fine except port 25 does not send email outside the firewall.
I have made some checks like
traceroute -n -T -p 25 gmail-smtp-in.l.google.com
resulting in:
1 * * *
2 * * *
3 * * *
4 * * *
5 * * *
6 * * *
7 * * *
8 * * *
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 * * *
15 * * *
16 * * *
17 * * *
18 * * *
19 * * *
20 * * *
21 * * *
22 * * *
23 * * *
24 * * *
25 * * *
26 * * *
27 * * *
28 * * *
29 * * *
30 * * *
it seems that SYN is blocked
any suggestions, please ?
After testing several firewalls to incorporate into a production environment. I finally chose opnsense, but now I have been having a problem for a few days and I can not find the solution.
I would appreciate if someone can help me solve it.
The problem is:
I have a mail server behind OPNsense 19.1.4-i386, I have configured nat forwarding in 993,465, 587,.. and 25 ports, and everything works fine except port 25 does not send email outside the firewall.
I have made some checks like
traceroute -n -T -p 25 gmail-smtp-in.l.google.com
resulting in:
1 * * *
2 * * *
3 * * *
4 * * *
5 * * *
6 * * *
7 * * *
8 * * *
9 * * *
10 * * *
11 * * *
12 * * *
13 * * *
14 * * *
15 * * *
16 * * *
17 * * *
18 * * *
19 * * *
20 * * *
21 * * *
22 * * *
23 * * *
24 * * *
25 * * *
26 * * *
27 * * *
28 * * *
29 * * *
30 * * *
it seems that SYN is blocked
any suggestions, please ?