Anwser Quick! RAID 5 has a dead HDD, would you hot swap a new disk or would you cold swap a new

[Praetor]

This is considering there are backups as well.

 

Please explain your points in a logical and if possible using best practices.

 

thanks all!

[Mindovermaster Global Moderator]

IIRC, if you are running AHCI mode, it wouldn't matter if you did it hot (system on), as they are hot swappable.

[TPreston]

Delete the entire array and restore the backup to a new RAID 6 Array. Don't use RAID5 anymore.

 

http://www.zdnet.com/blog/storage/why-raid-5-stops-working-in-2009/162

[Praetor]

Delete the entire array and restore the backup to a new RAID 6 Array. Don't use RAID5 anymore.

 

http://www.zdnet.com/blog/storage/why-raid-5-stops-working-in-2009/162

 

lol that's not even the question i requested...

 

also the array in question is very small in size, so it's still OK.

[froggyliver]

Is this for a server? Does it have a backplane? Does it support hotswap? If it does then why not replace it via hotswap?

[satysin]

If you can hotswap then hotswap. That is why we have such a feature.

[koppit]

if it supports hot swap then I'd say try it, especially if you have a backup, however I had one bad experience with a short on a drive power connection so when it comes to servers and raid 5 I consistently have good results shutting down, swapping, rebooting, then not touching anything in the command-line based raid console,. After getting back into windows and using the intel/adaptec/asi software to shut off the alarm, I mark it as a valid replacement, then rebuild from there. It never fails, even though the rebuild takes a bit of time and the server is slightly slower, the client usually feels better knowing that it's handled and will be back to normal shortly.

[rr_dRock]

Delete the entire array and restore the backup to a new RAID 6 Array. Don't use RAID5 anymore.

 

http://www.zdnet.com/blog/storage/why-raid-5-stops-working-in-2009/162

That comes from the same site that told people

 

"Keep using XP forever, it's not insecure as long as you install this third party product"

 

 

 

The reason behind hot swapping is downtime. If you can't afford downtime, hot swap.

 

If you've got the time to have that server down, cold swap.

[sc302 Veteran]

if it is capable of hotswap, by all means hot swap it.

[Praetor]

guys, i'm only interested to know if you guys prefer and why:

- hot swap

- cold swap.

 

forget the detail (server, raid mode, backups, etc.) as those are a non issue. I only said RAID 5 but it can be anything, really.

[Draconian Guppy]

If you have the ability to hotswap, why not use it?

[Mindovermaster Global Moderator]

Praetor, ignore the rest and do what we said, hot swap.

[sc302 Veteran]

Why hot swap is simple, you don't effect users as much. They usually don't even notice it. I have never had a server completely go down because I hit swapped a drive in.

[Praetor]

Why hot swap is simple, you don't effect users as much. They usually don't even notice it. I have never had a server completely go down because I hit swapped a drive in.

 

yes this is kind of response i'm looking for: simple, concise and direct to the point.

 

More?

[Tews]

You have been given the best advice out there.. What more do you want?

[Praetor]

You have been given the best advice out there.. What more do you want?

 

lol i just wanted to know what you guys prefer and why; i already do know what i prefer and use, just wanted to know if more people go for the hot swap or prefer (and why) the cold swap of dead disks.

[Hurmoth]

Delete the entire array and restore the backup to a new RAID 6 Array. Don't use RAID5 anymore. Don't use RAID6 anymore, err, in 2019.

 

http://www.zdnet.com/blog/storage/why-raid-5-stops-working-in-2009/162

http://www.zdnet.com/blog/storage/why-raid-6-stops-working-in-2019/805

Fixed.

 

:laugh:

 

Sorry, I had to add that. I have very little knowledge when it comes to this sort of stuff, so I looked up RAID6 to read up on it and that was the first article to appear.

 

Anyway, thanks for the link.

[REM2000]

please don't take this a rude however with a RAID either 5/6/10 or million in a degraded state if this is in a mission critical/production environment i wouldn't have time to ask a forum i would be either performing a hot swap or a cold swap, if another drive goes pop you are looking at downtime whilst restoring it, obviously you can have a drive go pop during a RAID 5 rebuild which is why generally RAID 6 is a good idea, i tend to use RAID 5 where the storage is kind of disposable. 

 

for your question i would go for hot swap as the service/data will still be available to end users and a rebuild takes ages so there is no telling how long it would be to rebuild your server during a cold swap, leaving you without a server / service for a day. Obviously the bigger the drives the longer the rebuild (and your servers RAID controller and HDD speed/perf). 

[daorbed9]

If you can hotswap then hotswap. That is why we have such a feature.

 

This is correct.  If the feature is disabled or you can't then it doesn't matter.  If you can then you should.  It's not going to risk hurting anything.  You might want to warn the users the performance will be abysmal while its rebuilding.

[snaphat (Myles Landwehr) Member]

yes this is kind of response i'm looking for: simple, concise and direct to the point.

 

More?

I think sc302's answer is pretty much the best reason. The reason against doing it would be if there was some physical issue with putting the new drive in where you suspected it could get shock or static or something like that. Why that would be the case? I don't think it would in any real world scenario unless you were replacing the drive next to cats walking on your server and rubbing on you :rofl:

[ANON86364]

If specific factors such as the existence of a backplane and down time are outside the scope of the poll, then factors such as environmental differences and physical abnormalities in a chassis should also be equally uninteresting.

 

As for my professional opinion, hot swap is the default. No reason why not.

[Praetor]

please don't take this a rude however with a RAID either 5/6/10 or million in a degraded state if this is in a mission critical/production environment i wouldn't have time to ask a forum i would be either performing a hot swap or a cold swap, if another drive goes pop you are looking at downtime whilst restoring it, obviously you can have a drive go pop during a RAID 5 rebuild which is why generally RAID 6 is a good idea, i tend to use RAID 5 where the storage is kind of disposable.

 

fortunately neither would i; this is just a single, honest question i wanted to ask because I've talked with fellow ITs about this and while some prefer hot swap (and i have my own preference, i just didn't disclosure so i could not affect the poll result) others prefer cold swap but none of them gave me a logical, proved reason for that, just this "gut feeling" or "past experiences" non sense that lacks real evidence.

 

thanks for the inputs guys; myself i ALWAYS hot swap disks (if supported), it's a great feature and only once I've deal with a server reboot while i was swapping a drive; it turn out that the array controller was going to die soon.

 

So, from what i see, the majority prefers hot swap and gave me some logical explanations, but for the very few that chose cold swap: why?

[Praetor]

Is this for a server? Does it have a backplane? Does it support hotswap? If it does then why not replace it via hotswap?

 

don't over complicate, this is just an academic question: what YOU prefer and why?

[Praetor]

Why hot swap is simple, you don't effect users as much. They usually don't even notice it. I have never had a server completely go down because I hit swapped a drive in.

 

well, unless if it was RAID 0... :rofl:

or a RAID controller problem.

[Shiranui]

If it's OK to shutdown for a few minutes, then cold swap.

Otherwise, just hot swap it.