IDE vs. SCSI reliability

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SickBeast

Lifer
Jul 21, 2000
14,377
19
81
Originally posted by: Kilrsat
A modern LTO, LTO2, or SDLT tape system would be a very nice companion no matter what drive solution you go with. All of these provide at least 100GB (native, double for the "compressed" figures) per tape, and the costs per tape in the $40-$60 range. These are proven technologies that give you more reliability and flexibility in your backup solutions. You can archive nightly, weekly, bi-monthly, etc. and be able to pull up a copy of a file from multiple points in the past. I'll grant that my archive experience is centered around large (2-5TB) data systems, but anything as valuable as that data cannot be trusted to a single backup.
Typically how much does a tape drive like that cost?

I hear what you're saying about the file revisions. A 5 DVD-R set backup of the 18GB of active projects once a week would be a very good idea. Long term reliability isn't critical since typically the projects last less than a year; it would simply be for the sakes of redundancy and being idiot-proof. ;)

Thanks for hammering home the fact that RAID-1 is not a backup. I guess the best idea would be to back up the arrays to USB at least once a day. I guess a lunch hour backup wouldn't hurt, and I don't think it would overburden the server too much to do it on-the-fly.

As for a contingency plan...I guess it would be format, reinstall, and copy everything. I need to reguarly back up all the user account information in Win2K server which I don't know how to do. Our uber-tech hasn't gotten back to me on it yet. I'm almost tempted to ghost the C:\ of the server onto DVD once I get the burner installed. Is Ghost the cheapest/best application for that?
 

mechBgon

Super Moderator<br>Elite Member
Oct 31, 1999
30,699
1
0
I like Automated System Recovery, a la WinServer2003. I did a little evaluation work on WS2003 for our non-profit agency and was rather impressed. Bare-metal recovery of a set-up Active Directory domain, on completely-dissimilar hardware in my case... in about an hour. I did have to install the mobo drivers.

I think maybe you should stop assuming that the cost of stuff is going to be a problem. Price it, discuss with your boss what each aspect has to offer, and let him absorb it and think about where he wants to draw the line. Give some real-world scenarios ("ok, let's say a guy is one month into a two-month project and he finds out he's just blown a week on something the client didn't really want. With the tape drive, we go back ten days. With just the RAID1, he starts from scratch. How often does this type of situation arise, historically? Is it something you'd like to spend about $1000 per year to 'insure' yourself against with the LTO drive and tapes, over a five-year lifespan? Sir? :D")

 

mechBgon

Super Moderator<br>Elite Member
Oct 31, 1999
30,699
1
0
Originally posted by: JediJeb
Originally posted by: mechBgon
JediJeb, you gotta hold a bake sale or something ;)


lol Dont think that hasnt crossed my mind at times.
I found out today we're supposed to be doing Technology Purchase Requests for mundane stuff like mice.

:confused: ~ It is not logical, Captain.

 

desy

Diamond Member
Jan 13, 2000
5,446
214
106
OK I'm hardly the expert on drive solutions, but there are best practices quidelines

So when I commented on SW raid its not because I've used it, I haven't, but because the people over at storage review who do look at this stuff everyday make sense. They do have some good things to say about it for Raid level 1 , but note the very last line, I've only ever bothered with Raid 5 where it truely doesn't make sense.

I was going to make the historical argument as well, thanks for the reminder kil :thumbsup:
Yes, people do walk into the office and beg you to go back in time, it is part of the backup strategy, to keep a retention period. Since you have a tape drive DDS4 ? 20-40 you can do a full backup once a week and appended incrementals the rest of the week.

When it come to capacity, you have to look at how the data grows, with digital cameras and bloated PP presentations? so IDE raid might be the way, like I said before if you have the data requirement, and in a couple/three yrs if your worried about the IDE drives . . . replace them, they are cheap enough.
I just used Tiger as a price baseline, its usually pretty good, but your in TO, somebody there should speak-up for a local guy!!

From Storage Review.

"There are a few advantages of using software RAID over hardware RAID, but more disadvantages. First, let's look at the pros of software RAID:

Cost: If you are already running an operating system that supports software RAID, you have no additional costs for controller hardware; you may need to add more system memory to the system, however.
Simplicity: You don't have to install, configure or manage a hardware RAID controller.
Duplexing: Duplexed RAID 1 can sometimes be implemented in software RAID but not in hardware RAID, depending on the controller.
That's pretty much it.

Now the cons:
Performance: The best-known drawback of software RAID is that it provides lower overall system performance than hardware RAID. The reason is obvious: cycles are "stolen" from the CPU to manage the RAID array. In reality, this slowdown isn't that excessive for simple RAID levels like RAID 1, but it can be substantial, particularly with any RAID levels that involve striping with parity (like RAID 5).

Boot Volume Limitations: Since the operating system has to be running to enable the array, this means the operating system cannot boot from the RAID array! This requires a separate, non-RAID partition to be created for the operating system, segmenting capacity, lowering performance further and slowing boot time.

Level Support: Software RAID is usually limited to RAID levels 0, 1 and 5. More "interesting" RAID levels require hardware RAID (with the exception of duplexing, mentioned above.)
Advanced Feature Support: Software RAID normally doesn't include support for advanced features like hot spares and drive swapping, which improve availability.

Operating System Compatibility Issues: If you set up RAID using a particular operating system, only that operating system can generally access that array. If you use another operating system it will not be able to use the array. This creates problems with multiple-OS environments that hardware RAID avoids.
Software Compatibility Issues: Some software utilities may have conflicts with software RAID arrays; for example, some partitioning and formatting utilities. Again, hardware RAID is more "transparent" and may avoid these problems.

Reliability Concerns: Some RAID users avoid software RAID over concern with potential bugs that might compromise the integrity and reliability of the array. While hardware RAID controllers can certainly also have bugs, I think it's reasonable to believe that some operating systems are more likely to have these sorts of problems than a good-quality hardware RAID controller would.

All things considered, software RAID doesn't seem to have much to recommend it. At the same time, realize that in many cases it is much better than using nothing at all. If you are running a small business, a software RAID 1 solution is far superior to running without RAID at all, especially if you aren't meticulous about your backups. (Then again, if you can afford two drives to do mirroring, a hardware RAID card is often only a small incremental cost...)"

 

Kilrsat

Golden Member
Jul 16, 2001
1,072
0
0
Originally posted by: SickBeast
Originally posted by: Kilrsat
A modern LTO, LTO2, or SDLT tape system would be a very nice companion no matter what drive solution you go with. All of these provide at least 100GB (native, double for the "compressed" figures) per tape, and the costs per tape in the $40-$60 range. These are proven technologies that give you more reliability and flexibility in your backup solutions. You can archive nightly, weekly, bi-monthly, etc. and be able to pull up a copy of a file from multiple points in the past. I'll grant that my archive experience is centered around large (2-5TB) data systems, but anything as valuable as that data cannot be trusted to a single backup.
Typically how much does a tape drive like that cost?
Unfortunately, the tape drives are probably out of your immediate budget, but its something you should be writing down and suggesting for future plans. Expect to pay ~$2500 for an LTO soltuion (100GB native/200GB compressed, ~$3500 for LTO2 (200GB native/400GB compressed), ~$3300 for an SDLT solution (160GB native/320GB compressed).

There are other formats, I listed the ones I'm most familiar with. Something like AIT-1 (40GB native/104GB compressed) will go for ~$600.

These are high upfront costs, but if the data is really as valuable as you say, a solid backup strategy really is priceless.
 

Kilrsat

Golden Member
Jul 16, 2001
1,072
0
0
Originally posted by: mechBgon
Is it something you'd like to spend about $1000 per year to 'insure' yourself against with the LTO drive and tapes, over a five-year lifespan? Sir? :D")
This is a very smart man. Listen to him :)

 

JediJeb

Senior member
Jul 20, 2001
257
0
0
How are tapes for long term storage, say I produce 100Gb per year of data that needs to be stored for 5 years, will the tape last if is isn't being refreshed regulary?
 

Googer

Lifer
Nov 11, 2004
12,576
7
81
Originally posted by: Kilrsat
Originally posted by: SickBeast
Originally posted by: desy
Now that its all sorted out ;)
Mirror your 18 gig drives, good idea
Add your 72 gig scsi drive 10K for $365 CDN at Tiger direct, you don't need 15K you said it was for archival purposes. Work out your backup solution, even a tape drive will be pretty expensive once in and with a rotation of tapes. What was the quote from the ISP for offsite? combine that with maybe your USB IDE drive ext your probably good.
If you ever gone through the ITIL process, availablity and continuity aren't something to sluff off.
Its a real cost from the buisiness point of view and easily eclipses HW in the bottom line.

Would you go with a single 74GB SCSI, or two IDE 250GB drives in RAID-1? Performance is not an issue, reliability only.

We have a 20GB tape backup system. It's a PITA and I was hoping to only use it on the 18GB RAID-1 of critical data. We have 36GB of data in total right now (both hard drives are 99% full). RAID-1 is a backup in itself in some ways. The USB drive is the second backup. Remote off-site storage is the third. I don't think we need anything more than that. An optical backup onto DVD-R every month wouldn't hurt.
RAID is not a backup!! This is a very important thing to understand. It is protection against hardware failure, but it is not a backup. A virus gets into one drive, the other is wasted too. A user overwrites the wrong file? That file is gone.

If the data is really worth $200,000/week, I'd look into a real backup solution that can provide a history. One of the most frequent conversations I've had regarding restoring from a backup:
User: "Can you restore file ABC?"
Me: "Sure"
I go and restore the file, fire off an email to the user
User: "Sorry, that copy isn't the one I need."
Me: "Ok, when was the last day you remember using the version you want?"
User: "Oh, it must have been a few months ago"

Now, with RAID that file is gone, with your USB solution that file is most likely gone. DVD-R has capacity limitations and hasn't passed long term reliability, especially with some discs being difficult to read as little as a year later.

A modern LTO, LTO2, or SDLT tape system would be a very nice companion no matter what drive solution you go with. All of these provide at least 100GB (native, double for the "compressed" figures) per tape, and the costs per tape in the $40-$60 range. These are proven technologies that give you more reliability and flexibility in your backup solutions. You can archive nightly, weekly, bi-monthly, etc. and be able to pull up a copy of a file from multiple points in the past. I'll grant that my archive experience is centered around large (2-5TB) data systems, but anything as valuable as that data cannot be trusted to a single backup.

I'd also like to stress the importance to verifying and testing your backups! A backup is no good if it doesn't work or you don't know how to use it. You should also have a disaster recovery plan on file and make sure every IT related person is aware of it. Planning for the "just in case" situation is very important, because if you run into a situation without a plan your emotions are running high, you're thinking on the fly, and you may end up doing more damage. A plan that is thought out in advance, using a clear head, and that passes a peer review may just save your rear.


Agreed, one virus or incorrect bit and the whole array is toast. Using IDE leaves you open to storing an incorrect BIT, since IDE does not offer any sort of error correction or checking.
 

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
Originally posted by: Kilrsat
Originally posted by: mechBgon
Is it something you'd like to spend about $1000 per year to 'insure' yourself against with the LTO drive and tapes, over a five-year lifespan? Sir? :D")
This is a very smart man. Listen to him :)
I hailed him on a secure channel right after I created this thread. I'm well aware of his vulcan-like poise and logic. Live long and prosper, mechBgon. :D
 

Googer

Lifer
Nov 11, 2004
12,576
7
81
Originally posted by: JediJeb
How are tapes for long term storage, say I produce 100Gb per year of data that needs to be stored for 5 years, will the tape last if is isn't being refreshed regulary?

I have some games on floppys that are from 1990 and 1991, I just recently pulled them out after not being used for at least 13 years so I could copy the data to CD and all checked out fine. However I have some floppies that are <5 years old that were heavly erased and re-written to seveal times that have tons of bad tracks and sectors. As for magnetic tape I cannot call my self an expert on the topic. But I believe if they are only written to once and Stored in a cool and dry place free of a magnetic source I think they sould be fine. But I would recopy and back them up every year to fresh meida. Hopefully when bule lasers come out you could copy the information to a blue-disc.
 

Googer

Lifer
Nov 11, 2004
12,576
7
81
Anyone know anything about cracking open a Compaq server case? Any surprises generally?

Nothing too scary in there, you may large funny shaped passive cooling device and a few proprietary parts (ram).
 

InlineFive

Diamond Member
Sep 20, 2003
9,599
2
0
Originally posted by: biostud
If it's just for a desktop/single user I would go for an IDE solution, but if it has to be a file server SCSI drives will probably be a lot faster.

Ditto.
 

Googer

Lifer
Nov 11, 2004
12,576
7
81
Originally posted by: PorBleemo
Originally posted by: biostud
If it's just for a desktop/single user I would go for an IDE solution, but if it has to be a file server SCSI drives will probably be a lot faster.

Ditto.


The question is not about speed here, he wants to know about reliabilty.
 

JediJeb

Senior member
Jul 20, 2001
257
0
0
Originally posted by: Googer
Originally posted by: JediJeb
How are tapes for long term storage, say I produce 100Gb per year of data that needs to be stored for 5 years, will the tape last if is isn't being refreshed regulary?

I have some games on floppys that are from 1990 and 1991, I just recently pulled them out after not being used for at least 13 years so I could copy the data to CD and all checked out fine. However I have some floppies that are <5 years old that were heavly erased and re-written to seveal times that have tons of bad tracks and sectors. As for magnetic tape I cannot call my self an expert on the topic. But I believe if they are only written to once and Stored in a cool and dry place free of a magnetic source I think they sould be fine. But I would recopy and back them up every year to fresh meida. Hopefully when bule lasers come out you could copy the information to a blue-disc.


I know on our old reel to reels it was suggested to refresh at least annually because the magnetic fields could bleed through in the layers of tape and corrupt data, just wondering if that was still the case with the newer DAT type tapes?
 

Googer

Lifer
Nov 11, 2004
12,576
7
81
Originally posted by: SickBeast
Originally posted by: Googer
I still don't get why such worry over a savings of $300 to protect data worth $10,400,000 (10.4 million) per year or 200,000 a week. At 200,000 a week the $1,000 cost is less than one half of one percent of 200k. Considering that these drives will be in use for 5 years the cost will amount to about $3.85 per week or .32¢ per user per week (12 users). SCSI is a cheap insurance policy to protect data that valuble.

IF this is really the job of your dreams and you would like a long and properous carrer then I would not trust this data to anything else. Protect your self as well as the data, It aint worth saving a few cents. Your boss and your clients will appreciate it.

My co-workers seem to like the sound of 250GB in RAID-1 as opposed to a single 74GB SCSI drive. I'll run down a proposal for two 74GB SCSIs in RAID-1 but honestly it's overkill IMO.

By the way, does anyone know if a RAID controller is needed for SCSI drives? A guy at a computer store started saying he was "MSCE certified" and "had been doing IT for 20 years" when I disputed the fact that I require a RAID controller. I know it works for IDE; it must also work for SCSI does it not?


If I understand your statement correctly, you do need a raid controller for SCSI just like you would for IDE. Like they say: "A+ is a certification, not a rating" Just because he is an MCSE does not mean Cr*p, he may know a lot about the Windows registry and Services, but probably not as much about harware as he wants people to believe.
When some one shouts out there certifications as a way to win an arguement, they are ususaly trying to hide the fact that they are ignorant and not sure of them self.
 

Googer

Lifer
Nov 11, 2004
12,576
7
81
Originally posted by: fixxxer0
googer and sickbeast pleast get a room lol

this is like your private sex thread the two of u take up 90% of the pages



SOME ONE PUT DUCT TAPE ON THAT KNOOBS MOUTH.
 

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
Originally posted by: Googer
Anyone know anything about cracking open a Compaq server case? Any surprises generally?

Nothing too scary in there, you may large funny shaped passive cooling device and a few proprietary parts (ram).

*Groan*...So I have to order the RAM from Compaq? That's outrageous...

I've never heard of proprietary RAM (thought it was SDRAM/DDR/Rambus, etc. - always a standard). I'll have to investigate. Thanks for the tips. :)
 

JediJeb

Senior member
Jul 20, 2001
257
0
0
Originally posted by: Googer
Originally posted by: SickBeast
Originally posted by: Googer
I still don't get why such worry over a savings of $300 to protect data worth $10,400,000 (10.4 million) per year or 200,000 a week. At 200,000 a week the $1,000 cost is less than one half of one percent of 200k. Considering that these drives will be in use for 5 years the cost will amount to about $3.85 per week or .32¢ per user per week (12 users). SCSI is a cheap insurance policy to protect data that valuble.

IF this is really the job of your dreams and you would like a long and properous carrer then I would not trust this data to anything else. Protect your self as well as the data, It aint worth saving a few cents. Your boss and your clients will appreciate it.

My co-workers seem to like the sound of 250GB in RAID-1 as opposed to a single 74GB SCSI drive. I'll run down a proposal for two 74GB SCSIs in RAID-1 but honestly it's overkill IMO.

By the way, does anyone know if a RAID controller is needed for SCSI drives? A guy at a computer store started saying he was "MSCE certified" and "had been doing IT for 20 years" when I disputed the fact that I require a RAID controller. I know it works for IDE; it must also work for SCSI does it not?


If I understand your statement correctly, you do need a raid controller for SCSI just like you would for IDE. Like they say: "A+ is a certification, not a rating" Just because he is an MCSE does not mean Cr*p, he may know a lot about the Windows registry and Services, but probably not as much about harware as he wants people to believe.
When some one shouts out there certifications as a way to win an arguement, they are ususaly trying to hide the fact that they are ignorant and not sure of them self.


It is needed only if wanting to do RAID in hardware. Only a SCSI adapter is needed to put drives in a non RAID configuration or to use the Windows Software RAID which I think was the argument he had with the salesman.
 

Googer

Lifer
Nov 11, 2004
12,576
7
81
Originally posted by: SickBeast
Originally posted by: Googer
Anyone know anything about cracking open a Compaq server case? Any surprises generally?

Nothing too scary in there, you may large funny shaped passive cooling device and a few proprietary parts (ram).

*Groan*...So I have to order the RAM from Compaq? That's outrageous...

I've never heard of proprietary RAM (thought it was SDRAM/DDR/Rambus, etc. - always a standard). I'll have to investigate. Thanks for the tips. :)


It is expensive to order ram from compaq/hp. but Crucual is usualy the suppler for Compaq and you can go to http://www.crucial.com/ and use the memory advisor tool. Enter the model of compaq you have and It will show you the correct dram module for you needs. Guarenteed to work for less $$$$.



SCSI RAID CONTROLLER- Faster and cheaper than adaptec
http://www.lsilogic.com/produc...scsi_raid/3202064.html
 

Googer

Lifer
Nov 11, 2004
12,576
7
81
Originally posted by: JediJeb
Originally posted by: Googer
Originally posted by: SickBeast
Originally posted by: Googer
I still don't get why such worry over a savings of $300 to protect data worth $10,400,000 (10.4 million) per year or 200,000 a week. At 200,000 a week the $1,000 cost is less than one half of one percent of 200k. Considering that these drives will be in use for 5 years the cost will amount to about $3.85 per week or .32¢ per user per week (12 users). SCSI is a cheap insurance policy to protect data that valuble.

IF this is really the job of your dreams and you would like a long and properous carrer then I would not trust this data to anything else. Protect your self as well as the data, It aint worth saving a few cents. Your boss and your clients will appreciate it.

My co-workers seem to like the sound of 250GB in RAID-1 as opposed to a single 74GB SCSI drive. I'll run down a proposal for two 74GB SCSIs in RAID-1 but honestly it's overkill IMO.

By the way, does anyone know if a RAID controller is needed for SCSI drives? A guy at a computer store started saying he was "MSCE certified" and "had been doing IT for 20 years" when I disputed the fact that I require a RAID controller. I know it works for IDE; it must also work for SCSI does it not?


If I understand your statement correctly, you do need a raid controller for SCSI just like you would for IDE. Like they say: "A+ is a certification, not a rating" Just because he is an MCSE does not mean Cr*p, he may know a lot about the Windows registry and Services, but probably not as much about harware as he wants people to believe.
When some one shouts out there certifications as a way to win an arguement, they are ususaly trying to hide the fact that they are ignorant and not sure of them self.


It is needed only if wanting to do RAID in hardware. Only a SCSI adapter is needed to put drives in a non RAID configuration or to use the Windows Software RAID which I think was the argument he had with the salesman.


You can use a raid controller to operate a single drive if you need. If that is what you are asking. you can also have two raid volumes on a single LSI Logic raid controller. LSI ROCKS!
 

SickBeast

Lifer
Jul 21, 2000
14,377
19
81
Originally posted by: JediJeb
Originally posted by: Googer
Originally posted by: SickBeast
Originally posted by: Googer
I still don't get why such worry over a savings of $300 to protect data worth $10,400,000 (10.4 million) per year or 200,000 a week. At 200,000 a week the $1,000 cost is less than one half of one percent of 200k. Considering that these drives will be in use for 5 years the cost will amount to about $3.85 per week or .32¢ per user per week (12 users). SCSI is a cheap insurance policy to protect data that valuble.

IF this is really the job of your dreams and you would like a long and properous carrer then I would not trust this data to anything else. Protect your self as well as the data, It aint worth saving a few cents. Your boss and your clients will appreciate it.

My co-workers seem to like the sound of 250GB in RAID-1 as opposed to a single 74GB SCSI drive. I'll run down a proposal for two 74GB SCSIs in RAID-1 but honestly it's overkill IMO.

By the way, does anyone know if a RAID controller is needed for SCSI drives? A guy at a computer store started saying he was "MSCE certified" and "had been doing IT for 20 years" when I disputed the fact that I require a RAID controller. I know it works for IDE; it must also work for SCSI does it not?

If I understand your statement correctly, you do need a raid controller for SCSI just like you would for IDE. Like they say: "A+ is a certification, not a rating" Just because he is an MCSE does not mean Cr*p, he may know a lot about the Windows registry and Services, but probably not as much about harware as he wants people to believe.
When some one shouts out there certifications as a way to win an arguement, they are ususaly trying to hide the fact that they are ignorant and not sure of them self.

It is needed only if wanting to do RAID in hardware. Only a SCSI adapter is needed to put drives in a non RAID configuration or to use the Windows Software RAID which I think was the argument he had with the salesman.
Yes, that was the discussion, and thanks to everyone for reinforcing what I was already pretty sure about.

My co-workers forewarned me about the guy at the computer shop, saying he wasn't very friendly. I called for a price quotation and ended up with someone yelling misinformation at me ($500 for a RAID adapter I don't even need). :roll:

Needless to say I'm trying to purchase the stuff elsewhere; it's just the convenience factor of the store and the fact that the firm has historically dealt with them. I hate rewarding bad customer service. :thumbsdown:
 

Googer

Lifer
Nov 11, 2004
12,576
7
81
Compressed data has a far greater chance of getting corupted than non-compressed data stored on a magnetic medium. That is why i am a proponent of uncompressed backups.
 

Googer

Lifer
Nov 11, 2004
12,576
7
81
Originally posted by: SickBeast
Originally posted by: Googer
Anyone know anything about cracking open a Compaq server case? Any surprises generally?

Nothing too scary in there, you may large funny shaped passive cooling device and a few proprietary parts (ram).

*Groan*...So I have to order the RAM from Compaq? That's outrageous...

I've never heard of proprietary RAM (thought it was SDRAM/DDR/Rambus, etc. - always a standard). I'll have to investigate. Thanks for the tips. :)

Compaq uses a special SPD that does not allow the computer to boot unless it has the correct ram. This is an old trick used by manufacturers for a long time now, to get you to buy ram from them.

Compaq, Dell, and I believe IBM or Gatewaty do this and have done this since the 80's