How to Make a Copy of a Virtual Disk (vDisk)?

Question

I would like to make a copy of a virtual disk and move it to an external drive. Is this possible?

Environment

KVM
OnApp Storage

Answer

Go to the VS disks page to get the identifier for the VS disk. It gives the identifier wjtgsfuyxapb3k.

Go to the compute resource or backup server and get the ID of the server you are on:

[root@  ~]# onappstore getid 
ipaddr=  result=SUCCESS uuid=2868323073 completion_time=0

CODE

Online the VS disk using its identifier and the server ID you are on as frontend:
```
onappstore online uuid=wjtgsfuyxapb3k frontend_uuid=2868323073
```
CODE
Map partitions of this VS disk, if needed (the identifier for the data store is required):
```
kpartx -a -v -p X /dev/iyrdh2t6lwkgcz/wjtgsfuyxapb3k
```
CODE
This should give you a disk, such as wjtgsfuyxapb3kX1.
Now you have the VS disk at /dev/mapper/wjtgsfuyxapb3kX1 and can perform tasks on it. For example, you can run fsck on it:
```
fsck -fy /dev/mapper/wjtgsfuyxapb3kX1
```
CODE
OR

Mount it and transfer the files:
```
mount /dev/mapper/wjtgsfuyxapb3kX1
```
CODE
After you are done with the disk, you need to undo the steps. First, umount the disk if it is mounted, etc. Unmap the disk:
```
kpartx -d -v -p X /dev/iyrdh2t6lwkgcz/wjtgsfuyxapb3k
```
CODE
Offline the disk:
```
onappstore offline uuid=wjtgsfuyxapb3k
```
CODE

Alternative Process

If the virtual server is on, create a snapshot and gain access to it as in the example below:

[root@  ~]# onappstore snapshot uuid=wjtgsfuyxapb3k 
result=SUCCESS uuid=b6yj75n1kz3wog completion_time=6 
[root@  ~]# onappstore getid 
ipaddr=  result=SUCCESS uuid=2868323073 completion_time=0 
[root@  ~]# onappstore online uuid=b6yj75n1kz3wog frontend_uuid=2868323073 
result=SUCCESS completion_time=11 
[root@  ~]# kpartx -a -v -p X /dev/iyrdh2t6lwkgcz/b6yj75n1kz3wog 
add map b6yj75n1kz3wogX1 (253:69): 0 41942912 linear /dev/iyrdh2t6lwkgcz/b6yj75n1kz3wog 128

CODE

Now you are ready to use the disk:

[root@  ~]# mkdir -p /mnt/snapshot_live_disk 
[root@  ~]# mount /dev/mapper/b6yj75n1kz3wogX1 /mnt/snapshot_live_disk/ 
[root@  ~]# ls /mnt/snapshot_live_disk/ 
bin boot cgroup dev etc home lib lib64 lost+found media mnt opt proc root sbin selinux srv sys tmp usr var

CODE

As you are done, you need to clean up the mount:

[root@  ~]# umount /mnt/snapshot_live_disk/ 
[root@  ~]# rmdir /mnt/snapshot_live_disk/

CODE

Offline and remove the snapshot:

[root@  ~]# kpartx -d -v -p X /dev/iyrdh2t6lwkgcz/b6yj75n1kz3wog 
del devmap : b6yj75n1kz3wogX1 
[root@  ~]# onappstore offline uuid=b6yj75n1kz3wog 
result=SUCCESS completion_time=6 
[root@  ~]# onappstore delete uuid=b6yj75n1kz3wog 
result=SUCCESS completion_time=9 
[root@  ~]#

CODE