Roman Gelfand:
> Looking at the tcp stream, below, of a smtp conversation, it appears
> there is 5 second delay before the actual smtp conversation begins.
> Is this normal behavior. If not, any ideas what/where specifically,
> in networking, I should be troubleshooting? No change was done to the
> server or any other machines on the network. This started happening
> all of a sudden.
>
> 15047 02:57:33.441270000 192.168.0.209 192.168.0.239 TCP 66 54398 >
> smtp [SYN] Seq=0 Win=8192 Len=0 MSS=1460 WS=4 SACK_PERM=1
> 15048 02:57:33.441494000 192.168.0.239 192.168.0.209 TCP 66 smtp >
> 54398 [SYN, ACK] Seq=0 Ack=1 Win=14600 Len=0 MSS=1460 SACK_PERM=1
> WS=16
> 15049 02:57:33.441515000 192.168.0.209 192.168.0.239 TCP 54 54398 >
> smtp [ACK] Seq=1 Ack=1 Win=65700 Len=0
> 15237 02:57:38.461112000 192.168.0.239 192.168.0.209 SMTP 97 S: 220
> pmx1.mydomain.biz ESMTP Postfix
It takes 5 seconds to look up the SMTP client hostname for 192.168.0.239.
- Turn off chroot per DEBUG_README instructions.
- Fix /etc/resolv.conf.
- Fix /etc/hosts.
- Fix /etc/host.conf.
- Fix the DNS zone for 0.168.192.in-addr.arpa
Wietse
