Raid Newbie - Info Please (back-up On Raid)

[CosmicSurfer]

Hi All... First some background info...

I'm just about to buy my New Dream computer.. and wouldn't you know it, but the external 2350GB HD I was using with my antique laptop... had a serious problem.. losing I don't know how much data... Of course, I don't have an Easy and decent back-up.. How do you back up almost 200 GB of data easily.... SO...

My NEW computer was going to have 4 Hdds, now it will have 5.

I was planning on using my 250GB as an Applications drive, after transferring the data to a larger 320GB Data Drive, with a second 320 to Back-Up the first. The O/S will be on an 80GB drive. But because the Data restore has left all my data a mess on the old 250, I've decided to get another 250 for Applications and then slowly re-arrange and restore my data to the 320. Isn't it wonderful how cheap drives are these days.

The old 250 will either stay as a seperate Back-up, or I'll uninstall it and use it in an external box as a backup- off site, or as an extension for my laptop.

Now to my Questions:

My MoBo will probably be the New ASUS P5KR, with On-board SATA RAID 0, 1 and JBOD. I'll have 3 GB of RAM, and either Intel Core 2 Duo 2.33 or 2.66 Mghtz Cpu.. Running Win XP-Pro.

- What is JBOD ?

- I'm planning on Using RAID 1 to create an immediate B/U to second 320.. But a friend says this will slow my computer down while it writes to the second drive.. Is this true? How much will it slow down?

- Is using RAID effective Back-Up?

- Can I run Raid 1 on my 2x 320 Drives for back-up, and at the same time run Raid 0, on my O/S and App drives? Will this speed things up? How is this done?

- Off Topic.. Speaking about Slowing Computer Down, the same friend says that there is a point of "Diminishing Returns' of using too much RAM... Is 3 Gb too much RAM with XP-Pro? Will it slow my system down?

- As I've been reading that CD-Roms/DVDs have a shelf-life and deteriate over time.. I definately want to back up to HD, not disk.. and I confess to being Lazy... What are your recommendations to a good, quick, efficient and easy, back-up plan?

Thanks again for any feedback,

CS

[onethailand]

My MoBo will probably be the New ASUS P5KR, with On-board SATA RAID 0, 1 and JBOD. I'll have 3 GB of RAM, and either Intel Core 2 Duo 2.33 or 2.66 Mghtz Cpu.. Running Win XP-Pro.

- What is JBOD ?

Just a Bunch of Disks. It basically combines all your hard disks into one huge virtual hard disk. Not what you want.

- I'm planning on Using RAID 1 to create an immediate B/U to second 320.. But a friend says this will slow my computer down while it writes to the second drive.. Is this true? How much will it slow down?

Yes it is true but it is hardly noticeable.

- Is using RAID effective Back-Up?

Yes. Saved my ass big time on more than one occasion. But if you're talking data backup only, not your OS and apps, then that's like driving a Ferrari to the corner store.

- Can I run Raid 1 on my 2x 320 Drives for back-up, and at the same time run Raid 0, on my O/S and App drives? Will this speed things up? How is this done?

You cannot run RAID on different size hard drives, except for JBOD. (edit: well actually you can with some controllers, but it will size the bigger drive down to the size of the smaller drive - not very practical).

Assuming you had two different pairs of equally-sized (generally, same model only is best), it would depend on your controller but you should be able to set up two different arrays, one with RAID 0, and one with RAID 1.

- Off Topic.. Speaking about Slowing Computer Down, the same friend says that there is a point of "Diminishing Returns' of using too much RAM... Is 3 Gb too much RAM with XP-Pro? Will it slow my system down?

Why do you need 3 GB of RAM? Unless you're doing something extremely memory intensive, like Photoshop or 3D, that 3GB is just going to be a big waste on XP. It won't slow your system down, except at initial boot-up if you set memory error checking to on.

Also, the next step up from 2GB is usually 4GB.

I would love to hear where your friend got his/her theory of diminishing returns. Unless he/she meant that RAM will become less useful as you put more in - in which case that is correct - otherwise known as overkill.

- As I've been reading that CD-Roms/DVDs have a shelf-life and deteriate over time.. I definately want to back up to HD, not disk.. and I confess to being Lazy... What are your recommendations to a good, quick, efficient and easy, back-up plan?

HD probably has a shorter lifespan... a CD-Rom or DVD, kept in a cool dark place, should survive quite some time. But I always keep a back up on HD as well, knowing the way my kids treat DVDs...

Edited October 2, 2007 by onethailand

[Firefoxx]

JBOD: As onthailand said.

RAID1 slowdown: True, but not really significant. The data integrity is well worth it.

RAID as backup: RAID 1 and above, it's considered instantaneous backup and usually a preventive measure for hard disk failure. It's not a "real" backup, in that it can't protect against other things (user error, loss of the whole machine through theft/fire, virii, etc. etc.). You have offline backups for that (tape, disc, whatever).

RAID on different drives: First, keep in mind that although RAID 0 speeds things up, it also increases risk in that if you lose one drive in a pair, you lose everything. It speeds things up but not by much really. Might as well just RAID 1 them, or don't RAID 0 them.

Diminishing returns: Depends on how you use your computer and what OS you're using. Generally, with 98, it was around 512MB, with XP it's around 1GB for light use, 2GB for heavy. With Vista (32), can't really say, since it's not stable enough yet. But then again, ram is DIRT CHEAP these days, so you're not paying that much, even for diminished returns.

CD shelf life: Yep, they deteriorate, but it depends on a lot of things, but two things most importantly: how you store them and how good they were in the first place. If you store them well (out of light, without physical abuse, etc), they tend to last quite a while. If you get quality (made in Japan) media in the first place, they also tend to last. I have quality CDR media that I wrote since the days of SCSI 2X speed drives (more than a decade ago) that still can be read without errors. I also have lousy DVD-R media that I wrote a few months ago and can't read today. Thing is, quality media is VERY hard to find in Thailand (I get them from the US) and if you can find it, it's too expensive. If it's very important, it's always a good idea to have at least two backups in two different types of media.

[Gary A]

I'm certainly NOT a fan of CD's for keeping data. I had everything backed up on CD's that I brought with me from the US as well as maintaining all my backups here on CD's. When I finally needed the data most of the CD's were useless. They were kept in sleeves and stored in a plastic CD storage box. A techie friend of mine had a look at them and told me a fungus destroyed them. I had never heard of that but further research told me that it was indeed true. A few of them were stored in the plastic individual boxes and they were in no better condition.

My techie friend held the disks up to the light and told me to take a look. There were small places where the light was shining through. He said the fungus eats the silver backing.

Edited October 3, 2007 by Gary A

[Firefoxx]

That's the thing about CDs. Their recording layer is the same layer as the label layer. If the label layer is damaged, then the recording layer is damaged... a good way to make sure someone can't read a CD is to simply use a sharp object to score the label side (scoring the recording side won't work... you can polish it and it'll still be readable). I had a bad batch of Kodak Gold CDRs, all made in Austria, of which the "gold" recording/label layer would come off in flakes. Nearly all of them did that. However, I also have a decade-old Sony "gold" CDR (made in Japan) which is still flawless. Again, it's all up to the media you use. That's why whenever I want to archive important data, I always use discs made by "Taiyo Yuden". If you buy them from the US, they're not that expensive, but if you buy them here, they're about 4-5x as expensive as normal media. Nearly all media sold today comes from Taiwan (and later China), and it's not going to be reliable.

DVDs fixed the CD problem by moving the recording layer into the middle of the disc. You can do what you like to the label layer, the recording layer won't be affected.

[Hmmm]

I would get an external USB drive like a Lacie of sufficient size to backup just the irreplaceable stuff (ie not the OS or the apps). Then, use a program like Retrospect that does incremental, compressed, backup. There may be freeware that does the same thing.

You can schedule backup overnight if your PC is left on, or just run it before you turn off. The incremental backup will only backup files that have changed since the last backup.

A typical default 'grooming' policy should give you multiple full backup copies - one per day for the last week, one per week for the last month, one per month for the last year, etc. All within a space smaller than the disks / partitions that are being backed up together in the one place.

Edited October 6, 2007 by Hmmm