EHLO: different size allowed, from different servers to ext
When I telnet to an external SMTP server from different servers on our network. EHLO answers with different allowed mail sizes. 30Mb from server 1, only 3Mb from another server.
EXAMPLE to yahoo SMTP server:
telnet 67.28.113.10 25
EHLO
answer if I try it from our server 1:
220 mta177.mail.re2.yahoo.com ESMTP YSmtp service ready
ehlo
250-mta177.mail.re2.yahoo.com
250-8BITMIME
250-SIZE 31981568
250 PIPELINING
anwer if I try it from one of our other servers:
220 mta162.mail.re2.yahoo.com ESMTP YSmtp service ready
ehlo
250-Requested mail action okay, completed
250-8BITMIME
250 SIZE 3072000
quit
221 mta162.mail.re2.yahoo.com
Does anyone know what the reason can be? Thank you very much for your help.
Best Regards,
Nico
1 Reply
It was a rule on the firewall. (Inbound = very strange since it is outgoing).
another thing that is very strange:
Why does the external SMTP server answers with the size that our FW allows, and not with what is allowed on -in this example yahoo's SMTP server?