Questions about RAID

[fallenapples]

I have a 500 GB HDD in my current rig, I want to do a RAID 1 array with another 500 GB HDD.

By creating a RAID 1 array will it create a copy of my files every so often in the case of a failure, or do I have to do it manually?

And if I add a 1TB HDD instead; will its capacity increase to 1.5 TB or will it choose the lowest capacity? Also will RAID 1 increase HDD read and write times?

 

[Kharn]

No RAID 1 is a duplexed copy of a drive;

One set of Data over Two disks, you would also need to create a new aray with a fresh install you can't normally copy data from a non raid environment to a RAID environment, single files yes but you can use DD or such to go from a single disk to RAID 1.

Edit to add:

There might be a work around for going from non RAID to RAID, however I am not aware of one that works reliably.

Ask for your disk question no you can't go from 500gb to 1Tb and then 2Tb with the disks, at least with the lower cost RAID devices, some might have a clone to failover and rebuild but most don't.

 

[fallenapples]

I plan to do a fresh install. So which array would allow me to have a back up in case of drive failure and produce good read and write speeds?

 

[Kharn]

RAID 1, if you just want a hdd back up (I still advise a 3rd backup device for critical data) in case of drive failure.but I would also order 3 drives when building the array and put one in the back of the cupboard and when one fails use that drive but look around for better disks etc.

But I need to ask is Raid good for you? is this just a if it ****s up protection or a business requirement that data has redundancy?

 

[PP Mguire]

If you want a parity situation then get 3 drives minimum and do RAID 5. Speed increase with the added benefit of being able to lose a drive and replace it soonish.

 

[fallenapples]

It's just for recreational use, not professional use. Do the capacities have to match, as well as the rpm?

 

[kuyfh4698]

As folks have said, RAID 1 is purely for redundancy. The capacities do not have to match, but if you have one 500Gb disk and a Tb disk, you will still only have 1Tb of your data (2 copies of the 500Gb)- the extra 500Gb on the Tb drive would not get used.

 

[fallenapples]

So how could I achieve best performance with a back HDD. Would the 500 GB within the array.

 

[Fat.Clown]

It's just for recreational use, not professional use. Do the capacities have to match, as well as the rpm?

you can use any 2 disks.

but your entire RAID volume is limited by lowest capacity disk, speed is limited by the slowest disk as well.

if you pair up a 7200 RPM disk with a 5400 RPM disk, the speed will only be as fast as the 5400 RPM disk while the 7200 RPM disk waits.

for best results, is is recommended to pair up two identical disks. but you can upgrade the slower disk to faster disk later on if needed. just have to rebuild the RAID volume.

RAID is a not a backup. fire? flood? thunder? tornado? hurricane? tsunami?