copy large LVM volume(14TB) from one server to another

Question

recently，I have to copy a very large LVM volume()rom server A to server B. Below is the filesystem of server A and server B

-

server A

[root@AVDVD-Filer ~]# df -h 
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/vg_avdvdfiler-lv_root
                       16T   14T  1.5T  91% /
tmpfs                 3.0G     0  3.0G   0% /dev/shm
/dev/cciss/c0d0p1     194M   23M  162M  13% /boot
/dev/mapper/vg_avdvdfiler-test
                      2.3T  201M  2.1T   1% /test
/dev/sr0              3.3G  3.3G     0 100% /mnt

server B

[root@localhost ~]# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/mapper/VolGroup-LogVol00
                       20G  2.5G   16G  14% /
tmpfs                 3.0G     0  3.0G   0% /dev/shm
/dev/cciss/c0d0p1     194M   23M  162M  13% /boot
/dev/mapper/VolGroup00-LogVol00
                       16T  133M   15T   1% /xiangao/lv1
/dev/mapper/VolGroup00-LogVol01
                      4.7T  190M  4.5T   1% /xiangao/lv2

I want to copy LVM volume /dev/mapper/vg_avdvdfiler-lv_root on server A to LVM volume /dev/mapper/VolGroup00-LogVol00 on server B . The server A and server B is in the same IP segment.

IN the LVM volume on server A , there is all average 500M avi wmv mp4 etc.

I tried mount /dev/mapper/vg_avdvdfiler-lv_root on server A to server B through NFS , then use cp command copy. It is clear I faild .

Because the LVM volume is too big , I do not have good idea . I hope a good solution here.

I'm a chinese, my english is very pool. sorry

thanks everyone！

Answer 1

A tar pipe is probably best for this.

Answer 2

I'm not sure your commands accomplish your intent :-)

If you want to copy the CONTENTS of the volume group I would suggest using tar or dump/restore piped over SSH (create an appropriate volgroup on Server B & restore the data) - see the man pages for those tools for more info.

If you want to copy the volume group itself (structure as well as contents), ask yourself why & insist on a good reason. If you come up with compelling reasons look into drbd or something similar

Answer 3

i think i would use rsync over ssh in this situation.

if the transfer dies half-way, using tar over ssh, you won't be able to resume the transfer, you will have to start from scratch.

Answer 4

Your english isn't too bad, I think everyone will be able to understand.

To clarify one thing, do you want the contents of "vg_avdvdfiler-lv_root" to be transferred, or do you want the LVM itself (which might include things like snapshots)?

Answer 5

If you were feeling adventurous, you could set up DRBD between the two machines. This would bring the two in sync in the background.

Advantages:

• Doesn't require the volume to be umounted for the whole transfer (like blocklevel copy does).
• Doesn't leave a hole where files could change after copy starts, but before it completes (like rsync does).
• Resume-able.

Disadvantages:

• More complex set up, especially for the uninitiated.
• Requires a brief downtime for reconfiguration on existing node to get CLVM and DRBD set up.