Postfix problem : read timeout

[DarkBen]

My 3 ispconfig servers are on the same LAN. And when i do a telnet connection on the remote server (on which i can't send a mail) i have two differents results :

The ispconfig where the mail is deferred can't connect with telnet

My 2 others servers can do it !

My router is a Cisco and each one of my 3 servers have a static ip 195.101... ...

On my 3 servers i have the same config : Debian Sarge perfect setup install + ISPConfig

[falko]

Are you using the same firewall settings on each ISPConfig system?

[DarkBen]

Well,

i tested telnet connection on all my others servers in my lan and this is ok except on one (the server on which mails are deferred) !

i don't understand...

My firewall have the sames rules .... And i tested with firewall stoped and it is the same result

In fact i have an answer of the remote server but it takes 10 or 15 minutes !!!

telnet ***.***.***.***.fr 25
Trying ***.***.***.***...
Connected to ***.***.***.***.***.
Escape character is '^]'.
220 ***.***.***.***.fr ESMTP Service Ready
421 ***.***.***.***.fr Error: timeout exceeded

What can i do ?

[falko]

Is the IP address of this server maybe already in use by another system in your LAN?

[DarkBen]

No,

but today, it is ok e-mails were sent !

I made no change on my server but all is ok now... Telnet connection on the remote server on which i had a problem is faster ! ...

I have no explanation except a problem on the remote server or on the router...

Thanks a lot for your help !