How to use two hard disks as a single, larger drive
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How to use two hard disks as a single, larger drive
I have a headless server set up on an old desktop with an 80GB hard drive. As you will all probably tell me in all caps, i need a larger drive. I recently acquired two 160 GB hard drives. I would like to be able to use the two hard disks as one 320-GB drive.
I've heard of something called "RAID" that might do something like this. From what Wikipedia tells me, I'm looking for RAID 0. Is RAID the right way to go to begin with, or is there something that I don't know of that's better? Or if RAID is the way to go, is RAID 0 the right one?
Sorry I have so many questions, as you can tell this is my first time trying something like this.
I have a headless server set up on an old desktop with an 80GB hard drive. As you will all probably tell me in all caps, i need a larger drive.
Why should we? We know nothing about your use-case,maybe 80GB is large enough.
Quote:
I recently acquired two 160 GB hard drives. I would like to be able to use the two hard disks as one 320-GB drive.
I've heard of something called "RAID" that might do something like this. From what Wikipedia tells me, I'm looking for RAID 0. Is RAID the right way to go to begin with, or is there something that I don't know of that's better? Or if RAID is the way to go, is RAID 0 the right one?
You can either use RAID 0 or LVM. I prefer LVM for its other advantages, but in that case I would guess it is a matter of taste. The only problem you could face is that if one disk fails all the data is lost, so if you store important data on it you will have to have a reliable backup solution.
Why should we? We know nothing about your use-case,maybe 80GB is large enough.
True. I should have told you that I use it to back up ALL of my files, and plan on backing up my parents'. In that case, it is too small. Good point, though.
Quote:
Originally Posted by TobiSGD
You can either use RAID 0 or LVM. I prefer LVM for its other advantages, but in that case I would guess it is a matter of taste. The only problem you could face is that if one disk fails all the data is lost, so if you store important data on it you will have to have a reliable backup solution.
I might be able to get an external HDD for that (doubtful, but the possibility exists). But since it's a backup, the data is stored somewhere else as well, so if it gets wiped I still have at least the copies on my laptop, and my parents have an external HDD on their desktop for backups, so if my server got wiped they would still have a good backup as well as the original.
As for RAID 0 vs. LVM, which is the most user-friendly on the command line? I'm running Ubuntu Server 12.04, and it's my first attempt at a terminal-only OS. (So far, it's working ) And (as you can probably tell) I have zero experience with either of them.
In that case I would go for LVM, since it has some advantages over RAID 0, like easy extensibility, flexible partition management and easier management in general. Have a look here to get a basic understanding: https://wiki.ubuntu.com/Lvm
When I get the chance, I'll actually do it, probably later tonight.
PS- Thanks you for your quick responses! I never thought that someone would see it this soon, help me find my way around what I'm trying to do, and have a potential solution only 2 hours after I asked the question. Thank you!
Check youtube as well for additional information, they have many tutorials on setting up and managing LVMs and RAIDs. You could search for generic instructions on LVM/RAID or instructions for a specific distro.
Also, reserve some free space if you want to do snapshots which is optional of course.
Unfortunately, I discovered that the hard drives are much older than I expected. I got them from my high school, and I wasn't expecting anything brand-new. Or even relatively new. I'm good friends with the system admin there, and she told me to just grab two hard drives right off the shelf that she keeps all the hard drives on.
One is dead, but still twitches when you poke it. Basically, when I start the computer, the drive spins up, and then it drops into a steady "slide,click..........slide,click" rhythm. BIOS doesn't recognize it. I booted from a Lubuntu liveCD. It recognized that there was 160 GB of something there, but it had no clue what it was. No SMART data, not even listed as a hard drive.
The other one is still kicking, but will probably die soon. Again, I booted from the liveCD. The SMART data has a power-on time of 3 years, and most of the parameters are "pre-fail" or "old age."
So neither of the drives are ideal candidates for a backup, as the backup will likely go out before the original.
I'll most likely be able to get another drive off that same shelf to replace the dead one, but I'll probably end up using the second one until it inevitably fails.
As you can probably tell, I run this server on what was other people's trash. The computer itself came from my mom's friend who was about to throw it away. I got a little more RAM from a friend at school, and the IT guys at my dad's office almost threw away the 80GB hard drive I used until this thread started.
The other one is still kicking, but will probably die soon. Again, I booted from the liveCD. The SMART data has a power-on time of 3 years, and most of the parameters are "pre-fail" or "old age."
You're not reading it correctly. Don't worry though, nobody does. You could grab a brand new disk off the shelf and it would say the same thing. It's not saying your drive is pre-fail, it's saying that if the associated threshold (one column to the left) were exceeded, that's what it would mean. Scroll up a few dozen lines for the
Code:
SMART overall-health self-assessment test result: PASSED
line, that's what you're looking for.
3 years isn't that much. I'm looking at the smartctl results for one of my machines right now, sitting at about a 6 year power-on time (51680 hours). And right next to it are two more machines that have been running 24/7 with their original drives since 2005 and 2006 respectively (they're too old to even have smartctl).
Last edited by suicidaleggroll; 01-10-2014 at 10:32 PM.
OK, thanks. I wonder why it lists everything as "pre-fail" or "old age"? I guess technically, everything is "pre-fail", as it is a value that happens before it fails . But the 3 years was listed as "old age", but you described this as not a major concern. To me, that says that the hard drive companies just want to get more people to buy their drives by making them think that their current one is almost dead. I just love the way they do things. Don't you?
As for the "slide-click" drive, am I right in my assumption that it's dead?
OK, thanks. I wonder why it lists everything as "pre-fail" or "old age"? I guess technically, everything is "pre-fail", as it is a value that happens before it fails . But the 3 years was listed as "old age", but you described this as not a major concern. To me, that says that the hard drive companies just want to get more people to buy their drives by making them think that their current one is almost dead. I just love the way they do things. Don't you?
Re-read the first part of my post:
Quote:
Originally Posted by suicidaleggroll
You're not reading it correctly. Don't worry though, nobody does. You could grab a brand new disk off the shelf and it would say the same thing. It's not saying your drive is pre-fail, it's saying that if the associated threshold (one column to the left) were exceeded, that's what it would mean.
Notice how the "pre-fail" and "old age" are under the "type" column? They're saying that's the type of warning that WOULD be issued, if you exceeded that threshold: http://sourceforge.net/apps/trac/sma...ctlReports_ATA
Now I'm not saying your 3 year old drive is going to last forever, just that 3 years doesn't mean it's about to fail either. Drive lifespan depends HEAVILY on temperature. If you bottle up a platter drive in a sealed box with no ventilation, it's going to fail very quickly. If you stick a fan right on its face, it will probably last for a very long time. So it all depends on what those first 3 years looked like. On my personal computers, I used to lose a drive (out of ~5) about every year or two until I started putting fans on them. I haven't lost a single one since...that was in 2002. Now I have lost drives on the machines at work, but when you have over a hundred drives running 24/7, eventually one is going to fail. I probably lose one of the hundred drives on those machines about every year and half.
Quote:
Originally Posted by maples
As for the "slide-click" drive, am I right in my assumption that it's dead?
OK, I think I see what you mean about the SMART data.
As for the fan = longer life, everything is stock: there's a fan in the power supply, and the CPU has a fan that goes over the heatsink, but it does pull air from the inside of the computer to the outside. The only air intake is on the front, and flows around the hard drives, so I think that I have decent enough ventilation.
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