Mirror RAID Synch. How often to schedule the Synch

[LD]

The Synchronizing schedule takes significant resources and slows down other multitasking tasks. There are two drives in the RAID (1TB each). The SW Synchronizing schedule defaults to once per day, which takes a few hours for the synch to finish and can be difficult to work while it is in progress. I've scheduled the synch for the evenings, but I sometimes work then too. The options are Daily, Weekly or Monthly. My question is, would a weekly synch be appropriate?

[speed]

I don't know what hardware/software/os config you are using but I'd set sync to Never. However I would set the monitoring software to alert me on error/drive failure even if you have a hot spare, you can also set it to verify the array once a month.

You do have valid backups don't you, so even if the array completely fails you can restore from them.

[chrisJumbo]

It depends on how much data you can afford to lose. We back-up daily, but we don't work at night so don't notice the resource drag. At home, I'm not nearly as diligent, but if I made major changes I do my best to let the back-up start when I'm done. So if you happen to be working when it starts, pause it, and re-start when you are finished.

cd :O)

[LD]

I backup regularly, so it's not a matter of losing data, as I back up important data to a separate external drive. Its more about having issues with either the drives or the software.

One issue is performance as the sw hogs resources while it's synching every night, making working while the synch is on - a little frustrating. I don't, however, want to leave the system on 24/7 to let the synch run overnight either, but I've noticed the sw does find some errors and corrects them.

The second issue, whether it's sw related or just one heck of a series of coincidences, is that I've gone through several drives since the RAID was installed about a year ago. It's happening too often to be coincidence so I'm thinking it's the software.

[claybutler]

I'm not sure I understand. Are you backing a single hard drive to an external RAID 1 array? So you have three copies of everyhting at any one time (1 source plus two mirrored versions)?

If I was doing that I would have the RAID array update every night.

In my own system I have six 1TB hard drives broken into three pairs of RAID 1 arrays. My OS and programs are one array, and then my files are split among two more RAID arrays.

So I always have a duplicate of everyhting important in real time.

Then every sunday a backup is made of my OS and programs on a single external drive.

[LD]

Two drives in the RAID (appears as one) and run the OS, applications and store data files. I back up the data to an external hard drive every second day. I have the external drive so if my system goes down for what ever reason, I at least have my data/source files to work with on another system. The thing is, I've been told by one sys admin to scrap the RAID software and go with hardware, which requires a clean re-install of everything. The company that installed the current RAID drives and sw says they have current systems configured this way in place and have run flawlessly for more than a year. I seem to have issues with drives every 8 weeks or so. Having said that, I think it's too much of a coincidence to think I'm just getting bad drives.

[claybutler]

They may be correct. My motherboard has a raid controller so it's a hardware solution not a software one.

But you don't have to do a clean install to convert to a hardware solution. You could take any one of the two drive and install it on another RAID array and it will automatically rebuild the RAID with whatever other drive you install. I've broken apart and reassembled RAID arrays many times. I'm even using two single drives from two separate arrays as single stand alone drives right now. They're both just sitting there in an external HD dock. I use them like single drives but they are actually each 1/2 of a two RAID arrays I broke up.

[LD]

So installing a hardware RAID controler on a system like mine which already is utilizing sw RAID does not require reinstall of the OS or the applications? See, I thought the sw had control over the whole drive, including the OS. Hmmm.

BTW, the sw is by AMD - RAIDXpert, if that matters.

[claybutler]

I don't think it would. In a RAID array the two drives can also work independently.

It would be very easy to test. Install the RAID controller (this won't harm the current sw array). Then pull one of the drives off and use it as the master (that's not the correct word, but it will be the drive that the other blank HD builds from). Then see if it rebuilds it self. Then disconnect the sata cable from the old array so th drive is isolated. Then reboot and and durring the boot proccess hit F8 over and over again untill you get to a screen that allows you to select which drive to boot from. Choose the new array and see what happens. If it boots then it worked.

Now I'm not an expert on any of this, I've just broken apart and rebuilt my arrays several times and one of the broken arrays is actually my old Vista OS so I have a dual boot.

[LD]

Well, I'll tell you, this will be the last time I go through replacing and rebuilding a new drive, although the system still "limps" along with one drive, which of course negates the whole purpose of RAID. I will pass this info on to my computer support to see if they can concur - which I hope they do. I don't want to go through another OS and apps reinstall as it takes the better part of a day to get everything working properly.

Thanks for your input Clay.