Author Topic: LMCE standard backup vs. Raid  (Read 1061 times)

roberto99

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LMCE standard backup vs. Raid
« on: August 15, 2008, 09:55:57 am »
Hi all

I am wondering about the following:
LMCE has a backup function already included. But as I know it does not (for example) back up the files of diskless MD's, right? So if it is like that this is not a complete backup solution. I then would rather use software raid by fist installing ubuntu, setting up the raid and then install LMCE on top of it. If it works I dont know, I am going to try, but am I right that the standard backup function of LMCE does not back up the files of the disless MD's (and what else .... who can tell me) or am I wrong?

Thanks
Roberto

jondecker76

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Re: LMCE standard backup vs. Raid
« Reply #1 on: August 15, 2008, 01:29:52 pm »
Take a look at the script responsible for generating the backup here http://svn.linuxmce.com/pluto/branches/charon-merge/src/BootScripts/PlutoRestorePoint.sh

From A brief glance at it, it appears to backup
-pluto_main database
-asterisk database
-files needed by the web admin
-the pluto.conf config file


Basically, it would be used to backup your installation so that you can restore that backup on a clean install if you had to do a reinstall. It doesn't backup media or other files not specified.

Regarding running a RAID on the root - I would advise against it. There was a recent bug report filed in mantis where someone tried this very thing. LMCE found the superblock and auto-detected the RAID and treated it as it would any other RAID array - causing cyclic sysmbolic links and other problems. This may be fixed in a future version, but for now I wouldn't do it.

Also - regarding RAID. They aren't bulletproof. I have lost data and so have others on a RAID array. It helps, but it also helps to understand how it (mdadm) works underneath so you know what to do when there is a problem. Asside from that, I don't think running the OS on a RAID is needed anyways. The OS is free and replaceable. The data isn't. If I were you I would:
1) Use a separate system disk for the OS
2) Create the backup points in the web admin on a schedule. If your OS ever did go bad, you can clean install a new one and restore from the backup (this should take care of most things except custom changes to config files)
3) Keep your data on a RAID array. This should give you some redundancy as well as the ability to do a reinstall on your system disk without fear of overwriting your data. Also, check the RAID status in the web admin at least weekly, as LMCE currently does not alert you on a disk failure. On top of that, a hot spare drive in your array is also a good idea

roberto99

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Re: LMCE standard backup vs. Raid
« Reply #2 on: August 15, 2008, 01:36:56 pm »
Hi Jondecker76 and thanks for all that info

Well, I am mainly concernet about the diskless MD's
I guess with a clean install and restore with the backup data I wont get my diskless MD's back, right?
If this is correct, how could I back them up?

Thanks
Roberto

Zaerc

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Re: LMCE standard backup vs. Raid
« Reply #3 on: August 15, 2008, 01:44:08 pm »
Try to keep in mind: RAID is NOT an alternative for making backups.
"Change is inevitable. Progress is optional."
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roberto99

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Re: LMCE standard backup vs. Raid
« Reply #4 on: August 15, 2008, 02:39:21 pm »
Ok, so how can I backup my diskless MD's ?
Any ideas
Would appreciate any ideas
Thanks
Roberto

jondecker76

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Re: LMCE standard backup vs. Raid
« Reply #5 on: August 15, 2008, 02:47:42 pm »
the Media  Directors are stored in the database as devices. There really is no backing them up, as they will be re-created if needed from the information in the database. So in a sense, the normal backup utility does back up the MD's (or at least the information to re-create them). Though, if you had custom changes for a particular MD, those would not be preserved.