Linux Production Server error

we have a oracle database and apps server separately and today there was a problem loggin in .
we restarted the database and apps (both linux servers) and still not able to

we then checked the logs in servers
ccd/var.log.messages

in db we coundt find any error but in apps we found that following error
Mar  8 09:09:02 prodapps kernel: Buffer I/O error on device hdc, logical block 128
Mar  8 09:09:02 prodapps kernel: Buffer I/O error on device hdc, logical block 129
Mar  8 09:09:02 prodapps kernel: Buffer I/O error on device hdc, logical block 130
Mar  8 09:09:02 prodapps kernel: Buffer I/O error on device hdc, logical block 131
Mar  8 09:09:02 prodapps kernel: Buffer I/O error on device hdc, logical block 132
Mar  8 09:09:02 prodapps kernel: Buffer I/O error on device hdc, logical block 133
Mar  8 09:09:02 prodapps kernel: Buffer I/O error on device hdc, logical block 134
Mar  8 09:09:02 prodapps kernel: Buffer I/O error on device hdc, logical block 135
Mar  8 09:09:02 prodapps kernel: Buffer I/O error on device hdc, logical block 136
Mar  8 09:09:02 prodapps kernel: Buffer I/O error on device hdc, logical block 137


we then tried to mount hdc oseparately
but the following error came then
/dev/hdc: Input/output error
mount: block device /dev/hdc is write-protected, mounting read-only
/dev/hdc: Input/output error
mount: /dev/hdc: can't read superblock

df -kh for apps server is
f -kh
Filesystem            Size  Used Avail Use% Mounted on
/dev/sda2             9.9G  6.6G  2.8G  71% /
/dev/sda1              99M   13M   82M  14% /boot
/dev/sda6             116G   61G   50G  56% /apps
none                  1.8G     0  1.8G   0% /dev/shm

there is no hdc filesystem   it is sda  so what is hdc then

and is the problem due to apps server