[TriLUG] Email issues

[S B]

Hi All,

I know this may not strictly speaking be a Linux question so I beg forgiveness in advance, but I'm hopeful someone will be able to point me in the right direction.

I'm having trouble sending email between 2 accounts I look after.

One is a domain on a dedicated server (Redhat+Plesk (qmail) ), the other is a shared/managed hosting account (cPanel) at a completely different provider.

Wehn I tried sending email in either direction between these 2 particular accounts, the email stalled for 4 days then bounces. Both accounts had no trouble sending/receiving with most (all?) other MTAs

I noticed SMTP on the dedicated server was very slow (20-30 sec delay) to accept email from my desktop client so I turned off the reverse-DNS lookup it was doing. This helped the speed at which I can send email out through it, but didn't improve the 'connection' to the shared/managed account.

After a long investigation and no resolution found, the shared hosting provider moved my managed account to another of their servers, and I was then able to send/receive email with the dedicated server.
However the client on the dedicated server reports they have the same issue with a few other (important) contacts.
Unfortunately moving my managed account also removed my test-bed to track down the root cause (but I needed my email fixs!!)

Has anyone seen similar issues and/or have suggestions as to what the underlying problem may be?

Simon...