How to mount a disk with symbolic links
First of all, we have to add a SATA disk to our server. Once this is done, we will have something similar to the following.
Contenido
- 1 Check system disks
- 2 Check if the partition is mounted
- 3 Mounting the partition
- 4 Checking if the partition has been successfully mounted
- 5 Setting up a mount point for the partition in /etc/fstab
- 6 Recreate in the new partition the directories you want to mount
- 7 Create a symbolic link
- 8 Rebooting
- 9 Check that the partition is correctly mounted
Check system disks
[root@disk ~]# fdisk -l
The command "fdisk -l" shows storage devices directly connected to our system:
Disk /dev/vda: 41.9 GB, 41875931136 bytes 13 heads, 48 sectors/track, 131072 cylinders Units = cilindros of 624 * 512 = 319488 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x8f0a35c1 Device Boot Start End Blocks Id System /dev/vda1 * 4 131072 40893440 83 Linux Disk /dev/vdb: 1073 MB, 1073741824 bytes 16 heads, 63 sectors/track, 2080 cylinders Units = cilindros of 1008 * 512 = 516096 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Disk /dev/vdc: 53.7 GB, 53687091200 bytes 21 heads, 12 sectors/track, 416101 cylinders Units = cilindros of 252 * 512 = 129024 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0xecfb8b84 Device Boot Start End Blocks Id System /dev/vdc1 * 9 416102 52427776 83 Linux
You have to check which device has the size of the assigned disk. We will note down the path of the device. In this example, we want to mount the device with this path: "/dev/vdc". We will mount the partition "/dev/vdc1".
Disk /dev/vda: 41.9 GB, 41875931136 bytes Disk /dev/vdb: 1073 MB, 1073741824 bytes Disk /dev/vdc: 53.7 GB, 53687091200 bytes
Check if the partition is mounted
Once you have located the device, you have to check if it is mounted in the sustem by using the command "mount":
[root@disk ~]# mount /dev/vda1 on / type ext3 (rw) proc on /proc type proc (rw) sysfs on /sys type sysfs (rw) devpts on /dev/pts type devpts (rw,gid=5,mode=620) tmpfs on /dev/shm type tmpfs (rw) none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
As you can see, the partition with path "/dev/vdc1" does not appear as mounted, so you can proceed with the mount.
Mounting the partition
In first place, you have to create the mount point (create the directory):
[root@disk ~]# mkdir /media/newPartition
Once you have created the mount point, you have to mount the partition of the aforementioned device:
[root@disk ~]# mount /dev/vdc1 /media/newPartition
Checking if the partition has been successfully mounted
[root@disk ~]# mount /dev/vda1 on / type ext3 (rw) proc on /proc type proc (rw) sysfs on /sys type sysfs (rw) devpts on /dev/pts type devpts (rw,gid=5,mode=620) tmpfs on /dev/shm type tmpfs (rw) none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw) /dev/vdc1 on /media/newPartition type ext3 (rw)
Setting up a mount point for the partition in /etc/fstab
You have to set up your system so mounting takes place each time a reboot occurs:
[root@disk ~]# echo "/dev/vdc1 /media/newPartition ext3 defaults 1 1" >> /etc/fstab
You have to check if the changes to "/etc/fstab" are correct using the command "cat /etc/fstab":
[root@disk ~]# cat /etc/fstab # # /etc/fstab # Created by anaconda on Tue Jul 12 03:55:42 2011 # # Accessible filesystems, by reference, are maintained under '/dev/disk' # See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info # /dev/vda1 / ext3 defaults 1 1 /dev/vdb swap swap defaults 0 0 tmpfs /dev/shm tmpfs defaults 0 0 devpts /dev/pts devpts gid=5,mode=620 0 0 sysfs /sys sysfs defaults 0 0 proc /proc proc defaults 0 0 /dev/vdc1 /media/newPartition ext3 defaults 1 1
Recreate in the new partition the directories you want to mount
Now you have to begin to recreate the directories that you want to mount in the new disk (in this example, only /var):
[root@disk ~]# cp -fr --preserve /var /media/newPartition/
Change in the original disk the name of the directory you want to migrate:
[root@disk ~]# mv /var/ /var.old
Create a symbolic link
After this, you have to create a symbolic link pointing from the new directory path (in the new partition) to the original path (in the old disk):
[root@disco ~]# ln -sf /media/newPartition/var/ /var
Everything done!
[root@disco ~]# ls -al /|grep var lrwxrwxrwx 1 root root 22 nov 7 17:26 var -> /media/newPartition/var/ drwxr-xr-x 17 root root 4096 feb 8 2012 var.old
Rebooting
Now you have to reboot to check that everything is ok.
Check that the partition is correctly mounted
[root@disk ~]# df -h Filesystem Size Used Avail Use% Mounted in /dev/vda1 39G 1,1G 36G 3% / tmpfs 1,5G 0 1,5G 0% /dev/shm /dev/vdc1 50G 247M 47G 1% /media/newPartition
