You could boot to a command prompt from original disc, then try to check hdb1 (e2fsck /dev/hdb1).
With a bit of luck, errors can be corrected. If not, there are other tools for fixing hardware - but as is is a server I woul replace that disc anyway.
If e2fsck works I suggest you get a new disc and copy everything from hdb. If it doesn't, reinstall on new disc.