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RAID 5 on Proliant 380 G5 slow to format D: drive
I'm doing a initial install of Windows 2008 on a HP Proliant Server that has a Smart 400 RAID controller. We have 6 148 GB 10K drives in a single hardware array set for RAID 5. The C: drive is 256 GB and was formatted fine during the installion of the OS. After the OS was installed I went back to format the remaining unused dick as my D: drive. Now after 7 hours the drive is only 25% done. The array parity is still building I think, but this is still really slow. Any ideas? Thanks
make sure write cache is enabled in the controller.
ASKER
HP only offers RAID 1 & 5. I didn't want to suffer the overhead of RAID 1 but I guess it may be a good idea now that we have ample drive storage. As far as I know there is no control of the write cache on Smart Array 400 controller other than let the battery run down. This machine is going to be hosting Exchange Server 2007.
Thanks
Thanks
ASKER
If I disolve the current array and reconfigure it for 2-drives RAID 1 and 4-Drives RAID 5 is it safe to install the OS while the array is still building? Also when I go to format the D: drive after the install is complete is it safe to do a QUICK FORMAT? Also it offers two types of formatting depending on the size of the partition. Which is best for the RAID 5?
ASKER
Upon further research I've learned that the full format option writes zeros in every byte of the partition rather then just clearing the volume like quick format does. I'm going to redo the array and specify quick format. Thanks
ASKER
Should software write caching be turned on in Windows if a machine has a hardware RAID conroller with on board RAM caching like the HP Smart Array 400? Something seems wrong now that my D: formatting has been running for 14 hours and is only 60% completed even though I understand that the format writes zeros into every byte in the simple partition.
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ASKER
Thanks for the quick reply. This is my first experience with a P400 controller. It appears by default the hardware cache is turned off by default from HP. How can I tell if the machine has a battery backup for the controller? I see no evidence of one on the mother board like there was on our 6I Smart Array controller. We have dual power supplies on the server and it is on a UPS so is it safe to enable the write cache if there is no battery on the controller and if so where in the Smart Array utility is this done?
Charles
Charles
If the cache is disabled you haven't got a battery. You'd see it readily enough with the lid off since it sits in one of the two stretched-D shaped housings moulded into the air flow baffle. (I======D shaped - cant do it in ascii graphics).
I think the option to turn write cache on without a battery is in BIOS (advanced system options) rather than under the ACU, it is on the G6 anyway although I'd never turn it on since server failure would equal data corruption which you wouldn't necessarily even know about. Far better to cough up $100 for a battery - http://www.hardware.com/store/hp/383280-B21
If you just want to turn on cache temporarily and can't find the option then under the ACU you can turn on disk write cache instead, again not something to do in a production environment but OK as a temporary measure to get the format over.
I think the option to turn write cache on without a battery is in BIOS (advanced system options) rather than under the ACU, it is on the G6 anyway although I'd never turn it on since server failure would equal data corruption which you wouldn't necessarily even know about. Far better to cough up $100 for a battery - http://www.hardware.com/store/hp/383280-B21
If you just want to turn on cache temporarily and can't find the option then under the ACU you can turn on disk write cache instead, again not something to do in a production environment but OK as a temporary measure to get the format over.
ASKER
Thanks, I did find the option to turn cache write on/off in the ACU and I did find two horseshoe shaped sockets that hold the array batteries which I will order. I did turn the caching on since we have redundancy on the server.
Charles
Only order one battery, it's got two places to put them since you might have two controllers.
ASKER
Thanks
You may have selected the full format versus the quick format which for a 470 GB might be awhile.
Not sure why you defined/setup the RAID in this way?
If I was setting this up, depending on what functions this server were performing the underlying requirements, I would have likely setup two 146GB drives in RAID 1 for the OS and the remaining four drives in raid 5 for the data.
146GB raid 1 C:
438GB RAID 5 D drive.
If it is a database a RAID 10 if available might be better if 292GB is enough for the storage i.e. the database is not yet large.