[mythtv-users] RAID 1 mirror with mythtv backend???

[Dan Wilga]

On 1/23/19 12:56 PM, James Abernathy wrote:
> The unknown part is how to take an old mirror from one system and 
> mount it in the new system without loosing the data. I've only created 
> empty RAIDs or replaced a failed drive and added it back in to the 
> mirror.

The metadata that describes the array is stored in /etc/mdadm.conf. If 
this is present in the new system, then mdadm will automatically find 
the drives and add them to the array, even if they are on different 
physical ports on the new system. It's very well-designed in this regard.

> I'm thinking about trying to eliminate as many variable as I can. I 
> have a spare PC. It's  Sandy Bridge (2nd Generation) Core i7 with 8GB 
> RAM. It has a mixture of 3GB and 6GB SATA ports. 
The one thing you may have trouble with is those 3Gb ports, if you use 
them for RAID. Having tried this for a while. I can tell you that 
rebuilding a RAID array with SATA 2 ports takes a significant amount of 
time more than SATA 3--something like a factor of 3-4 times as long. You 
won't have to rebuild the array when you swap the drives into the new 
machine, but if a drive ever fails, you will likely regret the slowness.