On Thu, 2009-08-20 at 00:49 -0400, Kok-Yong Tan wrote:
> Make sure there isn't a third party firewall installed on the
> machines that nobody thought to tell you about.
We get that at work once a year when McAffee Antivirus gets some update
and before anyone knows, it's blocking outgoing tcp/25 again (SMTP); it
seems to be some default setting (along with some other ports).
The the server guys are calling the firewallers again because "we're
being blocked when sending mail from our servers" - yeah right. I never
could understand why they were letting an antivirus program interfere
with their network stack...
I wonder however - didn't come across in this thread;
Anyone ever cared to check for successful mutual ARP resolution before
looking after lost ICMPs?
regards
Marc