Forum ©XSIBackup: ©VMWare ©ESXi Backup Software

clicream

Member

Registered: 2018-04-19

Posts: 27

Improper use of SMTP command pipelining (solved)

Hi,

Script manages to run backup but failed sending email. Below are errors related:

2018-04-22T14:29:54|  Opening port 25 for SMTPout-25 service...

220 mta2.domain.com ESMTP Postfix
250 mta2.domain.com
250-mta2.domain.com
250-PIPELINING
250-SIZE 204800000
250-VRFY
250-ETRN
250-STARTTLS
250-AUTH PLAIN LOGIN
250-AUTH=PLAIN LOGIN
250-ENHANCEDSTATUSCODES
250-8BITMIME
250 DSN
334 VXNlcm5hbWU6
334 UGFzc3dvcmQ6
235 2.7.0 Authentication successful
250 2.1.0 Ok
250 2.1.5 Ok
503 5.5.0 <DATA>: Data command rejected: Improper use of SMTP command pipelining
221 2.7.0 Error: I can break rules, too. Goodbye.
Firewall rule SMTPout-25 closed.

admin

Administrator

Registered: 2017-04-21

Posts: 2,055

Re: Improper use of SMTP command pipelining (solved)

Your server does not seem to support PIPELINING, just try with another server that does, a GMail account per instance

admin

Administrator

Registered: 2017-04-21

Posts: 2,055

Re: Improper use of SMTP command pipelining (solved)

Some clients report this issue very seldomly. It is due to the SMTP server being configured with a delay in between commands. Namely, if you don't wait some time in between SMTP commands, the receving SMTP server breaks the protocol on its own.

In case of (c)XSIBackup this can be fixed by setting the last field in the smtpsrvs.conf file to 1 (seconds) or above. One second is usually enough.

If you fell here trying to debug your own script, just add some sleep time in between SMTP commands.