You definitely have disk-related problems. It could be the disk controller. Whatever the story the error is at the OS level:
sh-4.1# perror 30 OS error code 30: Read-only file system InnoDB will stop working because it requires lots of writes to take place, even if it is reading
Here is what InnoDB looks like
The active InnoDB components requiring writes are
- Data dictionary (When creating, altering and dropping tables)
- Double Write Buffer (Copy of data to reuse in crash recovery)
- Insert Buffer (Mitigate changes in indexes from Buffer Pool)
- Rollback Segments/Undo Logs (Transaction Isolation and MVCC)
- Log Files (Receiving Changes From Log Buffer via Fuzzy Checkpointing)
.ibdfiles (Individual Tablespace files)
Once a file system turns read-only, all these moving parts stop.
You should back the data
- I would do a mysqldump of all the data
- Shutdown mysql and get an LVM snapshot (if applicable)
- Shutdown mysql and copy the datadir
Once you have a backup, get right to the disk maintenance. Check the RAID, the disk controller, and the disk itself.
Here are some other ServerFault posts on read-only issues