# service mysqld start
chown: `/webdata/mysql' の所有権を変更中: 読み込み専用ファイルシステムです
chmod: changing permissions of `/webdata/mysql': 読み込み専用ファイルシステムです
MySQL Daemon failed to start. mysqld を起動中:            [失敗]

EXT4-fs error (device vdd): ext4_mb_generate_buddy: EXT4-fs: group 144: 14340 blocks in bitmap, 
14339 in gd JBD: Spotted dirty metadata buffer (dev = vdd, blocknr = 0). 
There's a risk of filesystem corruption in case of system crash.
EXT4-fs warning (device vdd): empty_dir: bad directory (dir #393217) - no `.' or `..'
EXT4-fs warning (device vdd): empty_dir: bad directory (dir #393219) - no `.' or `..'
JBD2 unexpected failure: jbd2_journal_revoke: !buffer_revoked(bh);
inconsistent data on disk
ext4_forget: aborting transaction: IO failure in __ext4_journal_revoke
EXT4-fs error (device vdd): ext4_forget: error -5 when attempting revoke
EXT4-fs (vdd): Remounting filesystem read-only
Aborting journal on device vdd-8.
EXT4-fs error (device vdd) in ext4_free_blocks: Journal has aborted
EXT4-fs error (device vdd) in ext4_reserve_inode_write: Journal has aborted
EXT4-fs error (device vdd) in ext4_reserve_inode_write: Journal has aborted
EXT4-fs error (device vdd) in ext4_ext_remove_space: IO failure
EXT4-fs error (device vdd) in ext4_reserve_inode_write: Journal has aborted
EXT4-fs error (device vdd) in ext4_ext_truncate: IO failure
EXT4-fs error (device vdd) in ext4_reserve_inode_write: Journal has aborted
EXT4-fs error (device vdd) in ext4_orphan_del: Journal has aborted
EXT4-fs error (device vdd) in ext4_reserve_inode_write: Journal has aborted
EXT4-fs error (device vdd) in ext4_delete_inode: IO failure
EXT4-fs error (device vdd): ext4_lookup: deleted inode referenced: 1191615