robertperry Loc: Sacramento, Ca.

My 9 year old iMac went belly up last week. Made an appointment and took it to the Apple store in the mall. Tech hooked up his lap top, showed everything was good except the hard drive. He gave me the address to a computer place that can install a new hard drive for $200-$300 dollars. This company also teaches all the techs that work there at this Apple store. I'm going to get a new hard drive and use this one just for photography.

bpulv Loc: Buena Park, CA

This is new information. I have identified it as RAID-2 based on my apparent misinterpretation of definitions of the different RAID modes I have seen on the Internet.

As far as what I have said about the Drobo function, your explanation is not the impression I got from the Drobo website when I purchased it. It was my understanding that each drive was a mirror image of the other drives. I know performance is degraded with I swap drives, but that has never been a concern because I run the Drobo over night and the next day it is done. One time I had a hard drive fail. The red light flashed on the Drobo to warn me. When I replaced the drive with a new one, the Drobo rebuilt the new drive and then went back to normal operation as advertised.

Country's Mama Loc: Michigan

If I had the money to buy the computer that I want right now I would do it. If I can spend $300 or less and get through another year or two I can put money aside for the computer I want. Right now I would have to rob the travel fund or buy a computer I won't be happy with. I drive a 2005 Park Avenue also and am still dumping money into it. :) It is cheaper than buying a new one. No matter what I buy in 6 months it will be outdated. I guess because I refuse to go into debt for my toys.

Country's Mama Loc: Michigan

E-mail, Facebook and photography. Those are about the only thing my computer has to do. I was very impressed with the Apple tech I talked to. ( I live an hour away from the Apple store so I always start with online or phone tech. ) She spent an hour with me helping to diagnose the problem and give me my options. Unfortunately have it repaired by Apple was not one of them. :(
You were fortunate to have someone with that skill level available to you. Lets hope both of our computers give us years more of service.

TriX Loc: Raleigh, NC

Just don’t want to see you (or anyone else for that matter) get burned when you really need your backup to function.

First, RAID is a good thing - it adds redundancy or speed or both compared to a single drive. Here are the commonly used RAID levels.

RAID 0 - simple striping of data across multiple drives. You gain speed, but if any drive in the stripe fails, you lose everything - generally a bad idea.

RAID 1 - simple mirroring. Adds redundancy, but uses 50% of the space for it. Needs 2 drives minimum.

RAID 0+1 (or 1+0) - striping and mirroring. The favorite of DBAs. Roughly doubles the speed and adds redundancy, but still uses 50% of the storage for redundancy. 4 drives minimum and can survive a double drive failure DEPENDING on which two drives fail.

RAID 3 - byte striping with a dedicated parity drive. The best choice for large files such as imaging, but rarely available except for film/video applications.

RAID 4 - block striping with a dedicated parity drive. A good compromise between small file/large file performance. Mostly used by NetApp (Network Appliance) with their WAFL file system.

RAID 5 -block striping with rotating parity. The most popular current RAID level - allows multiple users to access different files simultaneously. 3 drives minimum. Can tolerate a single drive failure. 50% performance hit while in “degraded mode” while rebuilding data from a failed drive onto a spare drive,

RAID 6 - not a defined RAID level, but generally used to mean a RAID 5 with dual parity so you can survive a double drive failure.

There are other “made up by marketing” RAID levels like RAID 50 by small (non-commercial) RAID manufacturers of which there are dozens (like Drobo).

Now back to your specific case. Drobo allows simple mirroring (RAID 1) with 2 drives, RAID 5 with 3 or more, and “RAID 6” with 4 or more drives, which they combine into their “BeyoundRAID” virtualization. When you remove a drive, what’s happening is that you’re failing a drive (simulating a failed drive), and when you replace the drive with your rotating “spare”, the RAID goes into degraded mode and begins rebuilding the data onto the “new” drive. Depending on the nature of the rebuild (can it use the existing data on the drive or must it start from scratch), this can take from minutes to days with large drives. If another drive fails during the rebuild, there will be data loss.

What you should do is keep the 5th drive as a spare (forget the lock box trips), use the existing drives as you have been and replace a drive with the spare only if a drive fails. Also keep an off-site copy for DR (disaster recovery) as you have been, but do one of the following. (A) If you have good internet access, backup to a major cloud provider. The initial “seeding” of the cloud will take awhile (perhaps days), but afterwards you’ll upload only changes and new files (B) use a large off site drive as you have been. The drive needs to be large enough to hold the ENTIRE contents of the RAiD. Just mount it as an individual drive (not in the RAID) and either copy the data or use a backup or mirroring ap to regularly replicate the contents of the RAID onto this off site spare. Do this regularly (C) if not too large, do an initial and then incremental backups to MDisks (they are available up to 100GB each) which you move off-site (D) mirror your data to another system either on-site (which won’t protect you from a fire) or to a relative’s system at a different location (essentially the same as cloud storage, but much less reliable). Other than tape, which is impractical for individual users, these are the only methods I know that are reliable.

I hope this helps with your backup/DR strategy. You have a RAID system, which is certainly more reliable than a single disk. Now you just need to implement a good off-site DR/backup plan that you test to make sure it works BEFORE you need it. Personally, I mirror data to another on-site system, keep a copy of data in the cloud (Amazon S3) and archive important data on MDisks in a fire proof safe on-site.

Cheers.

Country's Mama Loc: Michigan

Thank you for all the information. I will look into it, though when I think about it most of what I am backing up and storing in the cloud has meaning only to me. :)

dennis2146 Loc: Eastern Idaho

I have never replaced a hard drive but my understanding (yes I know that means nothing) is it is fairly easy to do. There are computer parts stores on the Internet. Perhaps someone could recommend one that would sell a hard drive compatible with your Mac. Surely someone could replace it if you can find the hard drive.

Dennis

bpulv Loc: Buena Park, CA

Thank you.

burkphoto Loc: High Point, NC

I use both http://www.macsales.com (AKA OWC or Other World Computing) and http://www.ifixit.com. They’re both good sources of Mac drives, memory, and accessories. IFixIt has more of the other parts for Macs. Both have online videos and guides for doing the repairs/upgrades/replacements. They even sell the tools you need.

dennis2146 Loc: Eastern Idaho

Thanks for the information. I hope the OP can use it to her best advantage. I have never needed to fix any of my computers but have had for others to fix my PC's, never a Mac though.

As an aside, allow me to tell you how much I appreciate you and the information you offer to other members. Whether it is computers or cameras you seem to know a lot of information and are not hesitant to share with anyone in need. You and many other members who are in the same boat offer much to us without sometimes proper thanks.

Thank you,

Dennis

Country's Mama Loc: Michigan

Thank you for the info. We have purchased kits I believe from Ifixit for my cell phone. I have watched some of the videos. I think my husband could do it.I don't think my hands are steady enough. :)

Dun1 Loc: Atlanta, GA

I have been down that road. I have a have a mid 2011 27" Imac. The hard drive failed, I had the hard drive replaced by a local Apple Service Provider. Thank goodness for Time Machine Backup on an external hard drive. The hard drive was replaced with the identical 1 TB hard drive what was original to the machine. The out the door price for replacing the hard drive and labor at that time was $270. The cost to replace the hard drive is far less than the cost for a new Mac Mini, even given the forecast that Mac minis will be upgraded, the last upgrade by the way was 2014. Certainly with a new hard drive in the 27" Imac would be a more solid machine