[Linux-disciples] sda1 is not a valid block device

[Brian Cooke]

This morning, I started seeing this line repeated over and over again in 
my kernel log file:

Sep  1 05:19:15 experienced kernel: Buffer I/O error on device sda1, 
logical block ########
Sep  1 05:19:15 experienced kernel: lost page write due to I/O error on sda1

sda1 is a usb hard drive of mine (ext3fs).  When I try to mount it now, 
it simply says "mount: /dev/sda1 is not a valid block device"

Is my hard drive dead?  Or is just the file system corrupt?  I suspect 
the former, but I would like to confirm.  How can I find out?

Thanks,
Brian