[CentOS] Disable window scaling during kickstart

[Ray Van Dolson]

On Thu, May 10, 2007 at 07:04:51PM +0100, Plant, Dean wrote:
> Weird... Tell me about it, I spent a lot of time head scratching trying
> to figure out why network connections would just mysteriously hang.
> Eventually found reference to a problem with tcp_window_scaling and
> firewalls and after disabling tcp_window_scaling on my test CentOS 5
> box, everything started working.
> 
> The install does not get far enough for the shell console to be
> available, it hangs at the transferring stage2.img.
> 
> Dean

Ah, probably before %pre even has run (?)  Well you could rebuild the
kernel on the install CD to disable window scaling by default. :)  Ok,
not a particularly useful option... maybe someone else will have a
suggestion.

In HP-UX you can pass kernel parameters at boot-time, I wonder if
anything similar could be done?  Probably not.

Have you captured a tcpdump of what happens when the "freeze" occurs
with an intermediary system?  Maybe a setting could be changed on your
switch?  Although I would doubt the switch would be a factor.  Are your
packets going through an intermediary router?

I plan to do some network installs of CentOS 5 soon, will be
interesting to see if this issue occurs.

Ray