Hi,

I have a problem with copying a whole backup history from one server to another and preserve all hardlinks. First let me explain the situation.

I have a backup server with 4.5TB of backup data history all done with a script wich uses a combination of rsync and hardlinks to backup serveral servers in our network. It's a rotating backup script wich has been written by our previous systemadmin.
The structure is something like this :

/backup/backup.0/server1
/backup/backup.0/server2
/backup/backup.0/server3
/backup/backup.1/server1
/backup/backup.1/server2
/backup/backup.1/server3
/backup/backup.2/server1
/backup/backup.2/server2
/backup/backup.2/server3
etc.

A Cronjob runs every night wich rsync's all servers data with a rotation schema.
(it would be to much now to explain how the rotation works detail here)

I have setup a brand new backup server with 13TB of free space for backups. However i had to use a different filesystem for this to work.
I have used XFS as filesystem for this new server. The old one uses ext3.

Here comes my problem, i now want to copy all the (4.5TB) backupdata from the old server to the new server and preserve all hardlinks.
I have tried this with rsync with the options -avH (-H = preserve hardlinks) but that didn't work, rsync failed with an error (i forgot to write the error down :-(
I think because it is simply to much data to handle at once.
So i tried to use the rsync per directory.
I started with all data in the /backup/backup.0/ and rsync started without a problem and after almost 24 hours finished.
It transfered 2.5TB of data, however i could not see my hardlinks back when i checked with "ls -li " or with "find /backup/backup.0/ -type f -links +1" for example.
The hardlinks are made over the different /backup/backup.0, /backup/backup.1, etc
So i copied the /backup/backup.1/ also but all hardlinks are gone.

Anyone any idea what else i can do ?
I am at a loss here ... :-(

Thanks.

Perhaps you know the trick to transfer files preserving everything using tar, without actually creating the tar file. Basically it goes like this:
It seems that tar is not handling hard links correctly. There is a more extended tar available, S tar, which has a lot more options for dealing with hard links.
http://linux.softpedia.com/get/Syste...tar-1058.shtml
I have been using this program for years for making tape back-ups and it seems to be the least well known backup program. I don't have experience with the programs ability to handle hard links, but it might be worth looking at it. And 4.5 TB is a lot of data.

jlinkels

Thx jlinkels, i didn't know this tar trick.
I will install S-tar and give it try. Hopefully it will work.
Fingers crossed ...

Hi,

I have tried with S-tar but somehow it doesn't work as expected.
I created a simple testbackup directory with 1 dir inside and 1 file: (/testbackup/tdir.1/testfile)
then i used the command :
to make a hardlink copy.

Then i used the following s-tar command from the new server to copy the files from the old server to the new one:
This seemed to work just fine on the new backup server.
I checked with "ls -li /backup/testbackup/tdir.0/testfile" and same file in tdir.1 and the inode number (or whatever its called) is the same so linked files are copied fine.

However when i try the exact same command on my whole 4.5TB data spread accross different directories (backup.0, backup.1, backup.2, etc) it doesn't see the hardlinks. I checked during the process and i can not see hardlinks.

This is driving me nuts!
Any other suggestions anyone?
Thx