mirrored drive question?

[Ash5000]

OK here is a kinda general question

If i were to setup a mirrored drive situation RAID 1 software or hardware not sure which yet

I know it by definition is simultaneous write to both disk but is there any latency between the writing of both drives for example if the power goes out will the be any difference in what was written to both drives.. even if it is a milliscond?

Another thing on the mirrored drive setup if a database gets corrupt on one drive will that happen on both drives?

 

[Parcival21]

Hmm,
I don't have experience in these fields so I am not really sure if I'm right.
I think if you use a Raid Controller (hardware) there should not be any latency between the drives. Because the Controller will direct the data to both drives at the same time. But I don't know if you can be sure, that the drives will write the data in the exact same time, so you can't be sure in that point. But where will you realize a difference whether a drive is one milisecond faster or not?

To the second question:
A Raid Controller only controls the data. If you loose data because your database software has mistakes or any other reason that is not physical, the data will always be the same on both disks. Also viruses will be on both disks. That is one reason why you will still need backups although you have a RAID system.

bye, busche