Disaster Recovery

[SeanPF]

I am busy testing the disaster recovery procedure, and am having some problems. I am following the official instructions to test if they work http://doc.zentyal.org/en/backup.html#how-to-recover-from-a-disaster

I'm trying to install a backup of my Zentyal server onto a blank machine.

I used the GRLM boot loader, deleted the contents of the hard drive on this blank machine, and then went through the instruction listed above, copying the backup files via FTP to the blank machine. Everything worked exactly like it should.

Then I took the GRLM CD out of the drive, and rebooted the machine. Guess what... It didn't boot. It just said in NTLDR IS MISSING. Great, duplicity didn't make the machine bootable.

Ok, so it seems the recovering from a disaster instructions just restore your user files, but not the system files? So duplicity full-backups don't backup the system, only your files. I should have known.

So then how do I make it bootable?

I started over. This time I formatted the drive again and put a Zentyal CD in the drive. I installed a fresh copy of Zentyal on the blank machine.

When it finished installing, I took the Zentyal CD out and put the GRML CD in. Then I followed the disaster recovery instructions again, thinking "duh, I had to install Zentyal first before trying to use duplicity to recover my files."

Well, that doesn't work either! When I try to run the full duplicity restore, as in the instruction, I get several hundred errors saying: Error '[Error 17] File exists'

So what is the deal here? Can someone give me some more clear instructions, or at least a conceptual understanding of how this is supposed to work? I don't like that if there IS a real disaster that I have no idea how to utilize the backups that I do have.

[SeanPF]

Anyone have any thoughts? It seems like this hasn't been discussed on the forums anywhere?!

[ichat]

my gues - but im not a expert is...   the 1st attempt was correct, exapt for the part that you have to install a bootloader  (ie grub) ...

google  + howto install grub to mbr       should probably help you fix this problem.. as your error  looks as if there was a windows bootloader installed at the time...

you can probably get the  grub tools from a gparted disk..

[SeanPF]

That would be a pretty big step to leave out of the documentation, don't you think?

[ichat]

sorry - im not an expert, i have some knowledge of running ubuntu as a desktop for the last few years..
but professionally im stil a windowze admin...  

nor am i part of the zentyal team...     but if this is correct its a HUGE flaw in documentation.

[ian]

Backup/restore

There are several way's to solve this problem:

1) On the old server backup your data ( gzip, with webmin and copy the file to an externat disk etc ), then in the admin gui of Zentyal backup the configuration of the server, copy the result file to an external disk.

Install the new server , restore the data to the new server and from the zentyal admin gui on the new server restore the configuration. The new server is now ready to operate.

2) With tools like " Clonezilla, Acronis or Norton ghost " make an image of the old server, or clone the disk of the old server to the disk of the new server or put the image to the new disk.
The new server is now ready to operate ( this methode works if the old and the new server has the same hardware ).

Best regards,
Ian

[SeanPF]

Thanks Ian

But the idea is that my Zentyal server is shot, so I'm not able to access it. I want to restore the server with all of its files and settings onto a NEW blank machine using only the Duplicity backups that I have.

So far following the Zentyal documentation has proved fruitless.

[SeanPF]

3rd attempt:

- Installed blank machine with fresh copy of Zentyal
- Imported configuration file from broken Zentyal server, but this ended in errors. Some modules were configured correctly, some weren't.
- Used duplicity to restore only the /home folder, to get all the samba/user folders back. So far this is not working.

Zentyal documentation is mostly useless, I have found.

And I've come to the conclusion that Zentyal is not at all disaster-secure. If your server's hard drive crashes, welcome to a nightmare. Even if you have backups, good luck trying to actually USE them!

[christian]

Seanpf,

If you try to restore what was saved using Zentyal backup, it's pretty obvious that *everything* is not saved. Just look at the include/exclude section to convince you.
You're probably right stating that documentation should be improved. BTW you're very welcome to suggest anything you feel missing 
Given error message you got, it looks like you did a bit more than "deleting" content. This NTLDR error message is related to MBR pointing to missing Windows file. where is GRUB?

Assuming we emulate a real disk crash, I suppose you should start from scratch with unformatted disk or at least "linux ready" disk.
Does GRLM handle it properly? Frankly I don't know but will give a try because the point you raise is interesting.

[SeanPF]

Thanks for responding.

I know there are excludes. But the documentation seems to indicate that you can restore a fully functional system by using GRML and Duplicity to copy over backups. Is that not the case??

The blank machine I used in this test, to try to recover Zentyal onto, did indeed have Windows previously installed on it. But as per the documentation I used the the following commands with GRML to remove everything on the hard drive:

mount /dev/sda1 /mnt
rm -rf /mnt/*

Since the documentation didn't say anything about installing GRUB, I assumed that would be part of the restore process--but I guess it wasn't. So I think it's very important that the documentation include a section about how to make your disk bootable, or to make it 'Linux ready' as you put it.

I don't want to have to be a Linux guru to simply restore backups from a crashed disk onto a new one. I love Zentyal so far, but the inability to successfully recover from a disaster makes me very hesitant to use it in a serious business environment.

[jsalamero]

hi all,

that documentation might be outdated or with some missing step, long time since last time i checked it out. anyway, for production servers we recommend the disaster recovery add on which automates the whole process: http://www.zentyal.com/en/services/addons/disaster-recovery/

[SeanPF]

It would still be wonderful to know how to do it manually.

[ichat]

my steps would be to:   

1 install zentyal  -
2 create config -
3 install data -
4 backup data + config
4 destroy server...

1 install zentyal  *using stored profile if avail
2 copy backup'd data
3 * if not avail restore backup - using backup tool

or: 

1 install system,
2 configure system
3 use clonzila te backup a base system immage
4 install data.. and (if needed) aditional config
5 backup data + config
6 destroy server.
7 restore backup...
8 install data + config from backup..

[andrew.doades]

Brilliant. I've had the same problem and I've just about lost the will to live.

Last night I finally managed to get duplicity to restore a 20GB backup (this being the 12th attempt BTW) It took me a while because by default it was dumping all the temp files on the 600MB iso rather than /mnt/mytmp like I told it to. other attempts were on Virtual Machines, where half way through the Virtual Machine crashed.. so I dug out a nice Dell Optiplex 320 and started again

Came into the office this morning, see it had worked with no error, getting quite excited by this point, rebooted and errors. "no such device" and "you need to load the kernel first" errors. Thanks!