Hi.
I have a service that create a MySql database everyday. And the every database will be filled with about 40G data after created.
These databases are located in /data/mysql_data now. There is no doubt that /dev/sda4 will be full after decades of days. But as you can see below, I still has a lot spaces in /dev/sdb and /dev/sdc.
My question is: what's the best way to make MySql to use /dev/sdb (and then /dev/sdc) automatically after /dev/sda4 is full?

df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 9.9G 4.9G 4.5G 53% /
/dev/sda3 20G 812M 18G 5% /usr/local
/dev/sda4 885G 220G 621G 27% /data
tmpfs 3.9G 68K 3.9G 1% /dev/shm
/dev/sdb 3.6T 783G 2.8T 22% /data1
/dev/sdc 3.6T 924G 2.7T 26% /data2

Thx a lot!

A solution might be: making some soft links in /data/mysql_data when realizing there is not enough spaces in /data/, and located data files in another disk. But I think this might be not the best way. And the disadvantages are:
1. I cann't drop databases as before.
2. such shell script is kind of complicated, and I am not sure it will work in every context.

Simplest way would be to use a volume group that combines all of the drives together.

1 members found this post helpful.

Thanks, szboardstretcher!
I havn't used or even known "volume group" yet. And I have searched and learned some of it.
http://www.centos.org/docs/5/html/Cl...ger/index.html

I wonder whether the original data(or the other service that running on this machine but having no idea that a volumn group has been created) would be affected after I created a volume group?

You'd have to backup the DB and start over.
The LV/VG/PVs sit under the FS, so you also have mkfs.ext4 then put the DB etc back.

IOW: pv+pv+pv... = VG then carve into one (or more) LVs, then mkfs ontop of each LV, then install App SW.

HTH

PS I note that Section 5.1 of that link says '5.1. Creating an LVM Logical Volume on Three Disks', so follow that step by step AFTER taking 2(!) backups and checking them.

1 members found this post helpful.

I see. So the answer is that creating a volume group will destroy the data, which I don't want to. I cannot reformat the disk.
But thank you all the same!