Yum Update Locks Up Machine

[Robert L Cochran <cochranb@xxxxxxxxxxxxx>]

When I run

sudo yum update

it issues a message "reading repository metadata from local files"

and then my hard drive light goes on and stays on and the entire system 
locks up solid for long minutes. The update does not actually occur. It 
stops dead while the hard drive stays constantly busy. I tailed 
/var/log/messages but saw no unusual output printed to the log while 
this was happening. Version and kernel information:

[rlc@bobcp4 ~]$ rpm -q yum
yum-2.4.1-1.fc4
[rlc@bobcp4 ~]$ uname -a
Linux bobcp4.lingpgmr.com 2.6.15-1.1830_FC4smp #1 SMP Thu Feb 2 17:36:59 
EST 2006 x86_64 x86_64 x86_64 GNU/Linux


I tried `yum clean metadata' with the same result. I also tried booting 
the 1656_FC4smp kernel with the same result.

Any advice about how to fix this?

Thanks

Bob Cochran