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