If I had 2 500GB internal drives, should I use RAID to combine them? I don't know much about RAID, just that is sort of combines two drives. What are the advantages and disadvantages? What do you think I should do?
According to the laws of bad-luckology, the chance of drive failure is directionally proportional to the amount of irreplaceable important information stored on said drive. Those using a RAID setup, like yourself, may safely multiply this number by number of drives lacking redundancy. (In your case, being 2)
In short, drives fail. SMART status is good. and can warn you some times. But if one fails and you do lose data, you'll think twice. In my opinion, it is best to have 2 separate drives.
According to the laws of bad-luckology, the chance of drive failure is directionally proportional to the amount of irreplaceable important information stored on said drive.
So you want high reliability and expect to have lots of free space? RAID Level 1 (mirroring) is the answer. You get halved seek time and double read speed as a bonus.
So you want high reliability and expect to have lots of free space? RAID Level 1 (mirroring) is the answer. You get halved seek time and double read speed as a bonus.
Like Gon said - RAID 1.
You only get 500GB of storage, but absolute piece of mind.
If you're not doing tons of video work or need the space for any other reason, why go any other way?
Yeah, there's not much argument to this. If you bought the 2 drives because you need the space a RAID 0 setup is the way to go, it's no more likely to fail than if you just put two drives running independently. If you bought the 2 drives and don't actually need the storage space of the second (which I doubt) then steup a RAID 1. I know a lot of people recommended RAID 1 which is the safer way to go, but I doubt you bought that much space only to use half of it. Also, if you start with the RAID 0 and you decide to you can setup a RAID 0 and 1 array later even if your first array already has data stored on it.
RAID 1 is for pansies. With the quality of modern backup solutions, I don't recommend RAID 1 unless you are running production data systems or the like.
Load 'em up with RAID 0. It will be fast and furious, and the mean-time-between-failure is usually quite high. On top-quality SCSI drives, the MTBF is often rated north of 60 years (not sure how they get that number). Even if your consumer drive is only 200,000 hours, that's 22 years, and the percent chance that your RAID 0 will fail within 2 years is still relatively low. Probably on the order of 0.5% chance, if not less.
Yeah, there's not much argument to this. If you bought the 2 drives because you need the space a RAID 0 setup is the way to go, it's no more likely to fail than if you just put two drives running independently. If you bought the 2 drives and don't actually need the storage space of the second (which I doubt) then steup a RAID 1. I know a lot of people recommended RAID 1 which is the safer way to go, but I doubt you bought that much space only to use half of it. Also, if you start with the RAID 0 and you decide to you can setup a RAID 0 and 1 array later even if your first array already has data stored on it.
Very true. I purposely bought two 500GB drives because I will be doing heavy-duty video work. I didn't get the extra storage, only to use half of it. Doesn't that sound like a waste of money?
EDIT: For really, really, really important stuff, I'll put a duplicate copy on both 500GB drives, back it up on my external 200Gb drive, and burn it to DVD.
Very true. I purposely bought two 500GB drives because I will be doing heavy-duty video work. I didn't get the extra storage, only to use half of it. Doesn't that sound like a waste of money?
Well, no. Every setup discussed on this thread has upsides and downsides.
RAID 0 - fast read, fast write; if one drive fails you lose all data on both drives
RAID 1 - fast read, normal speed write; you have half the space; if one drive fails you lose no data, you do not even need to re-install OS or apps
separate drives - normal speed read, normal speed write; if one drive fails you lose all data on it and retain the data on the another
Neither type of RAID sounds like a waste of money precisely because you do heavy-duty video work and the added speed will be good for that.
if you're doing mission critical video work t5o a deadline, then why not go that little extra bit and get 2 more 500Gb drives and do raid 1 and 2 (its so long since i read up on my raid options im not sure if this is called raid 3.. i doubt it though )
this way you have NO down time in the event of a drive failure, AND you have the huge storage you need.
however IF you are very dilegent about backing up to that 200Gb external, then fine.
but you are still leaveing your data IN ONE PLACE UNTIL you backup.
with a mirrored raid set up you have it on 2 drives AT ALL TIMES.
always remember that: DATA DOES NOT EXIST UNLESS IT IS IN AT LEAST TWO PLACES.
ultimately you make a choice and you get on with it.
Oh heck, if he has 4 drives might as well set up a RAID 5 System like mine. It is the most efficient use of space for 4 500GB drives. 3 drives hold data and the fourth is parity in case one drive dies the data can be brought back.
Ok, what if I do RAID 1 and then I need more than 500GB later. Can I turn off RAID so I can get the extra storage?
Set it up however your heart desires. Go buy a 500GB external firewire drive. Backup all your data regularly. And you will not have to fret over lost data, anymore.
Comments
Disadvantages: One drive fails, you loose EVERYTHING!
Originally posted by Ebby
Advantages: Looks like one big honking drive. And you have sweet bragging rights for a while.
Disadvantages: One drive fails, you loose EVERYTHING!
so how likely is it that one of the 500GB internal drives will fail in a quad?
if it's very likely, i guess i shouldn't use RAID.
thanks for the quick response!
In short, drives fail. SMART status is good. and can warn you some times. But if one fails and you do lose data, you'll think twice. In my opinion, it is best to have 2 separate drives.
Originally posted by Ebby
According to the laws of bad-luckology, the chance of drive failure is directionally proportional to the amount of irreplaceable important information stored on said drive.
or information that you NEED RIGHT NOW...
http://en.wikipedia.org/wiki/Redunda...ependent_disks
How does this sound to you:
1st 500GB drive:
Mac OS X 10.4
Apps
Documents
Final Cut Studio
Family Photos
Family Music
2nd 500GB drive:
Website stuff
Family Video
Pro Video
Wow. I am going to have a LOT of free space.
BTW, what is the actual formatted compacity of a 500GB drive in a quad?
Originally posted by livatlantis
Where did you get these massive drives from? Wow!
BTO Quad
Originally posted by Agent Macintosh
BTO Quad
That's going to cost more than my car...which isn't saying much, but even so...
Originally posted by Gon
So you want high reliability and expect to have lots of free space? RAID Level 1 (mirroring) is the answer. You get halved seek time and double read speed as a bonus.
Like Gon said - RAID 1.
You only get 500GB of storage, but absolute piece of mind.
If you're not doing tons of video work or need the space for any other reason, why go any other way?
Load 'em up with RAID 0. It will be fast and furious, and the mean-time-between-failure is usually quite high. On top-quality SCSI drives, the MTBF is often rated north of 60 years (not sure how they get that number). Even if your consumer drive is only 200,000 hours, that's 22 years, and the percent chance that your RAID 0 will fail within 2 years is still relatively low. Probably on the order of 0.5% chance, if not less.
Originally posted by brclark82
Yeah, there's not much argument to this. If you bought the 2 drives because you need the space a RAID 0 setup is the way to go, it's no more likely to fail than if you just put two drives running independently. If you bought the 2 drives and don't actually need the storage space of the second (which I doubt) then steup a RAID 1. I know a lot of people recommended RAID 1 which is the safer way to go, but I doubt you bought that much space only to use half of it. Also, if you start with the RAID 0 and you decide to you can setup a RAID 0 and 1 array later even if your first array already has data stored on it.
Very true. I purposely bought two 500GB drives because I will be doing heavy-duty video work. I didn't get the extra storage, only to use half of it. Doesn't that sound like a waste of money?
EDIT: For really, really, really important stuff, I'll put a duplicate copy on both 500GB drives, back it up on my external 200Gb drive, and burn it to DVD.
Originally posted by Agent Macintosh
Very true. I purposely bought two 500GB drives because I will be doing heavy-duty video work. I didn't get the extra storage, only to use half of it. Doesn't that sound like a waste of money?
Well, no. Every setup discussed on this thread has upsides and downsides.
RAID 0 - fast read, fast write; if one drive fails you lose all data on both drives
RAID 1 - fast read, normal speed write; you have half the space; if one drive fails you lose no data, you do not even need to re-install OS or apps
separate drives - normal speed read, normal speed write; if one drive fails you lose all data on it and retain the data on the another
Neither type of RAID sounds like a waste of money precisely because you do heavy-duty video work and the added speed will be good for that.
this way you have NO down time in the event of a drive failure, AND you have the huge storage you need.
however IF you are very dilegent about backing up to that 200Gb external, then fine.
but you are still leaveing your data IN ONE PLACE UNTIL you backup.
with a mirrored raid set up you have it on 2 drives AT ALL TIMES.
always remember that: DATA DOES NOT EXIST UNLESS IT IS IN AT LEAST TWO PLACES.
ultimately you make a choice and you get on with it.
all the best with your new set up
Rod
Originally posted by Agent Macintosh
Ok, what if I do RAID 1 and then I need more than 500GB later. Can I turn off RAID so I can get the extra storage?
Set it up however your heart desires. Go buy a 500GB external firewire drive. Backup all your data regularly. And you will not have to fret over lost data, anymore.