[mythtv-users] warning for anyone with western digital green drives

[Jeff Siddall]

On 02/15/2012 07:17 PM, PJR wrote:
> There's only space in my 1U case (in the rack) for 3 drives, one SSD for
> everything except myth media storage, two in a RAID array for myth media
> storage.  I only need 'light' data redundancy as most of the myth data
> is TV programmes which if lost, who cares (except my wife if she hasn't
> seen her 'shows' yet), the rest is music and videos all (tediously)
> recoverable from original media.  I'm beginning to think that I should
> go back to my old system of occasionally manually backing up the myth
> media to a second drive. I'd prefer to have an 'automated' way of doing
> this since the combined FE/BE system shuts down when not recording (or
> playing) and wakes up by RTC alarm to record, hence automating a backup
> is not so easy.  Sounds like RAID is just too hard to get working (from
> a HW perspective) and judging by no recommendations, yet, as to suitable
> drives (meeting my requirements), that confirms it.

I am not trying to say RAID is too hard to get working because in 
general it is not.  But it only solves the problem of disk failure(s).

For more general redundancy you _really_ need to look at BackupPC:

http://backuppc.sourceforge.net/

It is a hidden gem that everyone should be using.  I will not say it is 
especially easy to get working, but it has some fantastic features and 
the investment in getting it setup once will give you perpetual peace of 
mind.

Specifically:

1. You can backup both local filesystems and remote filesystems over the 
network.  That allows you to run BackupPC and the associated backup disk 
on a machine far away from other machines (ex: your myth system(s)). 
Just keep in mind that gigabit LAN is a good thing if you are backing up 
tons of data remotely.

2. You can choose when stuff gets backed up.  The BackupPC server will 
ping the systems it backs up and start a backup when it sees a system 
come online.  You can also set a blackout period where backups only 
occur at certain times of the day (ex: I have mine setup to try to 
backup in the middle of the night).  If you have a system that is 
normally shutdown you can set up the BIOS or WOL to wake up the machine 
at the desired time.

3. You can choose what gets backed up on a system-by-system basis.  For 
example you could choose to backup /etc /home and  /<music directory> 
without backing up /<tv directory> on your myth backend.

4. You can choose how long you keep backups of various types to help you 
keep within the amount of backup disk space you have.  For example I 
keep full backups from 1, 2, 4, 8, 16, 32 ,64 and 128 weeks ago. 
Because it is smart enough to keep only one copy of each [identical] 
file having 8 full backups does _not_ take 8 times as much disk space.

There are tons of other good features too but I would be writing volumes 
to describe them all.  Suffice it to say it has capabilities far 
superior to any manual backups scheme.

Combine BackupPC with LVM snapshots (you are using LVM, right?) and you 
can have predictable, sane backups of all your important data.

Jeff