Ralf Hildebrandt:
> Today I found this in my log:
> Jan 12 22:39:39 mail postfix/postscreen[17030]: COMMAND PIPELINING from
> [216.46.18.51]:58366 after QUIT
>
> So I wondered -- "after QUIT?" and had a look at the client:
>
> mail:~# host 216.46.18.51
> 51.18.46.216.in-addr.arpa is an alias for 51.32/27.18.46.216.in-addr.arpa.
> 51.32/27.18.46.216.in-addr.arpa domain name pointer mail51.parafat.org.
>
> mail:~# telnet mail51.parafat.org. 25
> Trying 216.46.27.98...
> Connected to parafat.org.
> Escape character is '^]'.
> 220 mail98.parafat.org ESMTP Postfix (Ubuntu)
> QUIT
> 221 2.0.0 Bye
> Connection closed by foreign host.
>
> Would a Postfix instance trigger postscreen of another instance?
postscreen reports COMMAND PIPELINING when the READ operation
returned more input after QUIT<CR><LF>.
You have no evidence that Postfix actually sent that. It could be
a NAT firewall in front of other systems.
Wietse
