Install a new drive, format, partition and mount it, say as ‘/ssd’.
1. Change directory to new partition/location
# cd /ssd
2. Create new MySQL directory.
mkdir mysql
3. Assign the MySQL group and owner for the new data directory.
# chown -R mysql:mysql /ssd/mysql
4. Sync all the databases from old data dir to new data dir.
# nohup rsync -vrplogDtH /var/lib/mysql/ /ssd/mysql &
(nohup insures that the copy command runs even if the shell hangs and the sync status will be available in nohup.out)
5. Schedule a MySQL server shutdown during off-peak hours.
# /etc/init.d/mysql(d) stop
(In Cpanel servers, stop chkservd too, else MySQL will be restarted, if monitoring is enabled).
6. Sync the data again (will take less time to sync this time).
# nohup rsync -vrplogDtH /var/lib/mysql/ /ssd/mysql &
7. Once you have verified the data, delete the “/var/lib/mysql” folder.
# rm -rf /var/lib/mysql
8. Create a symbolic link from the new data directory to the old one.
# ln -s /ssd/mysql /var/lib/mysql
Note: Create a symlink to avoid changing the MySQL socket and data path in MySQL, PHP and other applications that need it, or adjust the mysql config to see the new path
