Thanks, it worked nicely. The ECN can also be disabled at runtime
changing the /proc/sys/net/ipv4/tcp_ecn to 0
Tomer H. wrote:
| Friday, April 30, 2004, 11:33:31 PM, Fernando Sanchez wrote:
|
| FS> -----BEGIN PGP SIGNED MESSAGE-----
| FS> Hash: SHA1
|
| FS> I've noticed that some servers do not allow my server to connect
on port
| FS> 25 for SMTP, when doing a manual test with:
|
| FS> $ telnet mx.some.server.com 25
|
| FS> from the server it just stays on:
|
| FS> Trying x.x.x.x
|
| FS> but if I try to telnet that remote server from another box on
mynetwork
| FS> I get the welcome message from the MTA on the other side. Does anybody
| FS> have had the same kind of problems? I try to search for my server on
| FS> sever black lists but is not on any. I was trying with tcpdump, but
| FS> don't know what to look for in the output. Any ideas?
|
| I have had this issue with linux once, failing to connect
| to one of ICQ's servers and to lists.netsys.com
| (full-disclosure@??? mailing list).
|
| The problem was with ECN, as their servers (ICQ & netsys)
| did not support it, and caused their firewalls probably to
| drop the packets.
|
| Over the Linux kernel v2.4 tree you will find it at the Networking
| category as: "IP: TCP Explicit Congestion Notification support", just
| disable it.
|
| HTH, Tomer.
|
| ----------------------------------
| Tomer H. tomer@???
| IT Solutions Provider
| www.metnix.com info@???
| ----------------------------------
|
|
- --
Fernando Sanchez
Dpto. Sistemas USFQ
