EXP 300 Raid Array, Newbe install

[lelton]

Question folks,
I am a totally newbe to IBM Exp 300 Arrays, but they look fun and I have experience with other Raid controllers. I have the Array attached to an Adaptec Ultra2 (80meg/sec) non-raid controller, using the correct cabling but when I boot the NT4 server it does not see any drive space on the 500gig, 14 drive Exp300 box, to format. The Two scsi lights on the Exp300 box light up (scsi activity and termination) for about one minute then .... go out. This has me concerned and I believe is the source of why I can not see harddrive space or do I need to boot from another utility to partiton the space first ?

I assume an IBM Raid controller is not required for operation or am I wrong here ?

As well the Adaptec controller is only an Ultra 2 controller (80meg/sec) but has the same High Desity cable ends as the EXP300. The cable is an defecto IBM cable spec'ed for the EXP300.

I assume that an Ultra 160 scsi adapter is not REQUIRED for operation and will just downgrade its speed but still funtion. Am I wrong here?


Any suggestions would be greatly appreciated.

Thanks,
Les

 

[LarryTheCucumber]

Do you have 2 SCSI cable attached?
Unless you split the backplane you need only 1 cable attached to either connector on the 300.

BTW The EXP 300 is a drive enclosure not an array.

 

[lelton]

Hum, I only have one cable attached right now using one server. I looked at the internal switches and the EXP300 box is configured to have a split backplane. I did not want to change that for fear of messing up and data/raid relationships right now. The box is fully filled with drives (14).

Our server has an Adaptec 3950U2D (Ultra Wide 2 80meg/second) card in it (non-RAID). It has the same Ultra High Desity cable connections as the EXP300 and the Adaptec card does not see it ! I have fiddled with Terminations, Termination Power and such but nothing seems to help. One issue I do see happening is when the server is booted the SCSI Activity light and Termination Power light, on the EXP300 lights up for about 1 minute during that boot up sequence, then both lights go out. Within the scsi bios I can not see any devices on that channel. Its almost as if the EXP300 sees the SCSI Reset on the bus upon server boot but nothing else.

My concern is that the EXP300 (160 meg/second) is not backwards compatible with a controller of a differnent spec. (80meg /second), no matter if the two are using the same scsi high density cable technology.

So,... me is hooped right now. (slang)

Question 2, you mentioned that the EXP300 is just a drive enclosure and not a RAID Array. Friggin dude who sold it to us told us it was an Array. If you don't mind, could you send me to any 3rd party tech website that deals with the EXP300 enclosures, if you know of one ? I have been on the IBM site for some time now, ... its realy unfortuately not that useful when you get into real technical questions. I couldn't even accertain that this box was an enclosure.

Question 3) have you seen the EXP300 attached to non-IBM raid and non-raid controller ? Is there a RAID controller you would recommend to work well with the EXP300. I was thinking of the IBM Netfinity SERVERAID 4H ULTRA160 SCSI 37L6889, but wanted to make sure I needed this card before I bought it.

Thanks for your brain dump and experience on these boxes.

Les

 

[LarryTheCucumber]

It should be backward compatible.
I have had them attached to Adaptecs before and IBM 3H RAID controllers.

But I think you need to pull either drive 6 or 7 out.
The Adaptec has a SCSI ID of 7 and so does the drive.
This may take care of the access.

#2. You create an array on the drives contained within a drive enclosure. There is no RAID until then.

As far as the data/raid on the drives, there probably is none. Without a model of the raid controller that was attached to it and if it was a single 300 attached to the controller, then you might read the config from the drives, if those are all original drive. Since it was resold it should have been wiped clean.

When attached to a non RAID controller all you will see are drives, the you would have to software mirror them.

For hardware RAID you will need a controller.

The 4H is ok. What type of system are you using?

 

[lelton]

Hi Larry,

I got it working ! It was a Termination issue. For some reason the manual termination jumpers would not work, nor would the "auto" setting within the adaptec card work. I had to either install and ACTIVE terminator on the other side of the channel or set the software to terminate at the card with terminator the HIGH side of the channel. Anyways, it works.

I took a heavly look at the 4H IBM card. It looks like a great card from a performance point of view .... but I am having a bear of a time finding correct drivers. I need support for some older OS's, most notable NT4 and Netware 4. I could not find either on the lastest driver matrix. As well ... I read a number of reviews stateing that the Windows 2003 cluster failover is not supported. We are in the process of converting our old NT4 database to two Windows 2003 servers in a clustered (Active/Dormant) setup. So .... I chose to go with two LSI RAID controllers.
The Ami 493 Elite 1600 U160 Raid controller, currently they come with 64meg, but I have ordered the ram to upgrade to 128, which is there max. I don't think we will need the batteries because we are in such a heavily UPS'ed environment, the chance of power loss without me doing something about it is minimal. But I guess it would be an issue if the power went down during the evening and we were in the middle of a backup... hum, will have to think about that one. BTW, what is the main advantage to having a battery on the RAID cards ? Is it only for transfering cached data in the even of card failure ? I have only killed one scsi controller once in the past 15 years of working on servers. And that was in the old days when scsi controllers were more of a bear to configure.

Our environment is an Accpac for Windows database server running Pervasive SQL (like Btreive but on windows). Its become a pig, ram can't be upgraded on that machine, NT has ram max issues, and the current drives are slow. That is why we decided on a drive Array ... well enclosure right now. BTW, totaly from a performance point of view. The Accpac database is only 3 gig, the rest of the server data is about 30gig but its just files. The EXP300 is fully loaded with 14 drives, 36gig, so about 504gig total. Would it be ok to leave the backplane split, and raid 5 seven drives to put all that NT4 data onto. That way I could preserve the other backplane side for other server needs. Or, should we use all 14 drives (actaully will be 13 if we have two controllers attached and not having the backplane split) and raid5 all 13 drives for the NT4 data?

I am looking for performance and my training/experience has always said, the more spindles the more performance. I just don't know the performance difference between 7 spindles and 13 spindles on a small 3 gig database ? Right now our accounting postout which used to take only 1 hour due to most of the data being in ram, has now moved to 17 hours !! The database is small, some of the files are big at around 250-400meg, and those are the main files we are posting to/processing.

I guess we should also ensure we have the largest block size as well. BTW, is there any thoery behind matching the block size to the drive array, or do we just go with the largest if the database has large files ?

Sorry, I am becoming a bit of a database junky ...

Anyways Larry, good to talk to you

Mr. Les

 

[LarryTheCucumber]

Mr Les,
What database are you using. We run Oracle, MS-SQL and UDB
for various things. The big ones are Oracle. 2+ Tbytes

Check you db documents, most have a recommend block size that is best for them. It is a balance between speed and wasted space. Somethings you want on mirrored drives,
some on RAID5, it all depends.

For clustering we quit using RAID adapters and went all SAN.

On our old clusters we used ServerRAID 6 adapters.