+ Jason Haar <[EMAIL PROTECTED]>:
| SMTP connections to our sendmail and qmail servers take over 80sec
| to return a banner when connected to _from_ machines on our own LAN
| (i.e. whose info is in our DNS - not the downed forwarder). [...]
|
| Once the initial delay is over, sendmail and qmail acts as normal.
|
| Any ideas why this is happening? Using strace I can see sendmail
| receiving timeouts from DNS lookups - although I can't see what it's
| looking up.
Probably it is trying an inverse lookup on the remote host's IP
address, possibly followed by a forward lookup.
You might test this by running
env - PATH=$PATH tcpserver -H 0 9999 printenv
on the server and trying telnet server 9999 from a client; compare
with what happens if you remove the -H flag, or even replace it by the
-p flag. You may also wish to experiment with the -R flag.
- Harald
