SMTP Proxy incoming - sender receives 451 error
Hello,
different senders get error while sending mails to my customer (firebox m390). This error the sender get:
Diagnostic-Code: smtp; 451 Requested action aborted: local error in processing
On Firewall log i get only this logs about that (debug is active):
2023-05-07 00:51:53 FWStatus, 0x3ac5e0e0-1403678 Queue empty, payload 'MAIL FROM: SIZE:84347\x0d\x0a' stays with event, pri=7, proc_id=smtp-proxy, msg_id=
2023-05-07 00:51:53 FWStatus, 0x3ac5e0e0-1403678 MAIL FROM: SENDER, pri=7, proc_id=smtp-proxy, msg_id=
2023-05-07 00:51:53 FWStatus, 0x3ac5e0e0-1403678 986046688:1403678: smtp command 'MAIL FROM: SIZE:84347\x0d\x0a', pri=6, proc_id=smtp-proxy, msg_id=
2023-05-07 07:06:53 FWStatus, 0x3a2b37e0-66144 Queue empty, payload 'MAIL FROM: SIZE:84347\x0d\x0a' stays with event, pri=7, proc_id=smtp-proxy, msg_id=
2023-05-07 07:06:53 FWStatus, 0x3a2b37e0-66144 MAIL FROM: SENDER, pri=7, proc_id=smtp-proxy, msg_id=
2023-05-07 07:06:53 FWStatus, 0x3a2b37e0-66144 975910880:66144: smtp command 'MAIL FROM: SIZE:84347\x0d\x0a', pri=6, proc_id=smtp-proxy, msg_id=
Does someone has an idea?
Comments
The firewall isn't seeing any payload traffic -- the sending MTA might be waiting for something.
the 451 from the server suggests that the problem may be on the sending or receiving side. Office365 uses 451 as a rate limiting response, so if the problem fixes itself, it's likely that.
-James Carson
WatchGuard Customer Support
We have that error, and the sending mailserver has the following SMTP dialog:
[...]
SMTP<< 250 Requested mail action okay, completed
will write message using CHUNKING
SMTP+> BDAT 1450
SMTP<< 250 Requested mail action okay, completed
SMTP+> BDAT 39361 LAST
(I'm on the sending side and can debug there) - The watchguard side offered
SMTP<< 250-Requested mail action okay, completed
250-SIZE 50000000
250-AUTH NTLM LOGIN
250-8BITMIME
250-BINARYMIME
250-CHUNKING
250 OK
and I guess that some of CHUNKING/BINARYMIME or so causes problems ?
Review this:
Troubleshooting SMTP Response 451 (Temporary Error)
https://www.cloudmailin.com/smtp-troubleshooter/451-error