Serious Postfix weirdness

[Jordan Gordeev]

Joerg Sonnenberger wrote:
On Sat, Nov 15, 2008 at 04:31:55AM +1100, Petr Janda wrote:
  
Is net.inet.tcp.path_mtu_discovery=1?

Joerg
      
No, it was set to 0. is it supposed to be set to 1? If so, should the default 
be 1? As far as documentation goes Ive read most of modern UNIX systems have 
it turned on by default.
    
It might help.

Joerg
  
Does anybody object to turning Path MTU Discovery on by default?
It's been more than 15 years since it was introduced and everybody had a 
chance to learn about it by now.
Is there a technical reason (e.g. related to where the Path MTU is 
stored), for having it off till now?