Replacing Hard Disks

[Shawn_75]

I have several Proliant 3000, all of which have fallen off warranty. They all are performing well and running Windows 2000.

The Hot Plug drives that are used by these servers are 1.0" 10K and are either 4.3GB or 9.1GB. The Raid controllers are SmartArray 3200s.

I'd like to replace the drives by putting in other SCA drives while using the existing drive trays. As this would be significantly cheaper than replacing the drives, trays, and cages in all the servers.

Can this be done? Is there anything I should watch for when doing this type of upgrade?

Thanks in advance

[Shawn_75]

I should also note that the trays are the older biege ones not the newer black ones.

[Tom Mucha_1]

This is totally possible as long as you can find the drives. Most of the new drive will be either Ultra3 or Ultra320. To my understanding, Ultra320 is not backwards compatible with Wide-Ultra - so you couldn't just swap out 1 drive at a time and let the 3200 rebuild it, you would have to do everything at once and restore your server. And I THINK (don't quote me on this) that the Ultra 2 and 3 drive will slow down to wide-ultra modes.

[Shawn_75]

What about the Ultra160's will they go back to Wide ultra?

[Tom Mucha_1]

Ultra3 is Ultra160. For some reason I'm doubting myself as to say they are backwards compatible... I'm looking for a better answer.

It's monday, brain still isn't working ;-)

[Tom Mucha_1]

Ok Shaun.... I've probably confused you by now, but I went and asked another person here, and he said that even the Ultra320's will throttle down to Wide-ultra speeds.

Going to get more coffee! Sorry for the confusion guys!

[Glenn Weavind_1]

The Smart3200 Raid controller only runs the disks at Ultra2 speed, and the old drive cage you've got only supports Ultra2 speed. The only useful thing you can do is upgrade the drives for more capacity, not more performance.
For ultra3 perf, you need at least a Smart5300 controller *and* to upgrade the drive cage (it's a standard spare part - and they're not very expensive) to take the HP/Compaq 'Universal' metal framed hot plug HDDs - and you need to upgrade the internal SCSI cable from controller to drive cage.
Beware that not all SCA drives actually support hot-plug, even when mounted in the old beige plastic trays. Check with the supplier before spending money.

[Ernest Ford]

The Ultra160 is backward compatible down to wide SCSI speeds - what you need to watch for is SE/LVD which can typically be set by a jumper.

For 10/15K RPM drives you might need to look at airflow - those babies run real hot.

I'm currently running Ultra160 18G disks attached to an Adaptec 2940 in a ProSignia 500

[Shawn_75]

I am looking for capacity not to increase speed performance. These servers keep running out of storage but rarely break 40% of channel capacity.

It is interesting to note that not *all* SCA drives will not work in hot plug configurattions. So is the operating in SE/LVD mode that allows usage in hot plug configuration?

[Ernest Ford]

Actually Shawn - until I read it here, I was under the assumption that all SCA drives support hot plug - so I can't comment on that, but the SE/LVD setting is not related to hot plug.

To explain very briefly - SE or single ended SCSI and LVD or low voltage differential SCSI describe how the SCSI bus is driven. A single ended connection has 1 signal wire and a ground return, whilst a differential connection uses 2 wires for each signal to allow for noise cancellation, higher speeds and longer cables.

Wide & Ultra-wide are SE, Ultra160 and faster are LVD, when you interconnect the devices, some drives will autosense and work, some won't and will need to be jumpered.

By the way - if you find devices that say differential SCSI rather than LVD - DO NOT PLUG IT IN - this is an older specification that works on the same principle as LVD, but uses higher voltages, high enough to cause damage!