Ray Van Dolson wrote: > On Thu, May 10, 2007 at 06:34:54PM +0100, Plant, Dean wrote: >> Hello List, >> >> Due to a problem with CentOS 5 and one of our firewalls I am having >> to disable tcp window scaling to stop network connections grinding >> to a halt. I am also trying to Kickstart CentOS 5 machines through >> the firewall so need to disable window scaling at install time. >> >> I have added to the kickstart file >> >> %pre >> echo 0 > /proc/sys/net/ipv4/tcp_window_scaling >> >> But the install still hangs while transferring the stage2.img >> >> Should the above %pre work or do I need to do something else to >> disable window scaling during the install. >> >> In case anyone's interested CentOS 5 is the first time we have >> suffered this problem both CentOS 3&4 worked without issue. > > Weird issue. Haven't seen anyone else have it (at least on this > list). > > Can you switch over to your shell console when the hang happens and > examine the value of tcp_window_scaling to see if maybe it gets reset > somehow? I believe %pre should work.... > 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