Drive Mirroring

[cjsj1]

Hi All

Just a query about a small server.

NW65SP4
2 X 160g HD’s
Usual Sys and Dos partitions and one big Data Partition.

I would just like to have them mirrored so if one fails everything will carry on a normal. But inside either NRM or iManager there only seems to be Mirroring options for any data partitions and not the sys even in the NSSMU you can’t seem to say mirror the whole drive but instead only single partitions.

Is it possible to mirror the whole drive including the Dos & Sys and Data partitions?


Thanks for anyone’s views on this

 

[TheLad]

I would consider hardware mirroring before software mirroring. Is that possible on your server setup?

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"It's true, its damn true!"
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[LawnBoy]

Agree with TheLad. Netware is some great stuff but not even they can pull pull off an efficient software mirror. I don't know of anybody who can.

 

[cjsj1]

Yes I can see your point of view (just have a tight budget) but surely it can’t be that bad. But I would have thought that the chances of 2 drives going down would be so slight and even then hardware Mirroring would fail as well.

This is how I see it

1. 2 drives mirrored via NW software
2. Both working and mirroring fine
3. one day ones drive fails
3. The system still carries on as if nothing has happened but you get the message that it has failed.
4. When you get the chance, replace the faulty drive and then get it to re-mirror
5. System same as before hardware failure

Does that look like it should?

 

[LawnBoy]

That is the way it should work, but there's a lot of overhead involved in software mirroring. If your server is already busy the extra load could bring it to it's knees.

 

[cjsj1]

Sorry forgot to say that this is my home server so it’s not exactly doing a lot so I am not too worried about how hard it has got to work.

So what I will do is get the second drive and put the dos partition on the same size as the main drive make it bootable. Then put in the second drive and then from the NSSMU utility mirror each of the partitions in turn to the new drive and viola I think?

 

[marvhuffaker]

Even low end SATA systems will do RAID 1 mirroring.. That's better than software mirror.

I understand this is a home system.. But in the event that a drive fails, the hardware mirror is much easier to recover from. This is not theory, it's from experience. No stats to back this up, but in general the hardware RAID handles the error conditions better. Yes Netware should continue to chug along on a software mirror, but I've seen cases where the drive fails and the system goes down instead. Depends on the controller and other conditions.



Marvin Huffaker, MCNE

http://www.redjuju.com

 

[cjsj1]

Thanks for the info Marvin.

I have finished the mirroring now so when I get home after work I will give it a little test and pull either the data/power cable out and see what it does and will report here.

I still must be in a better position now with this software mirror than I was with just single drives more chance of a total recovery if something goes wrong. I do have regular backups but think that it would be easier just to restart the system and carry on as normal until I put in a replacement drive.

I will report back on what happens

 

[cjsj1]

Well I got home and did the test

I pulled the data cable out and the server lasted for about 15 secs before going down moaning about not seeing the missing drive.

After a restart it was all fine and dandy no errors with only one of the mirrored drives. I did test the drive I disconnected as well on its own and that was fine too.

So it does work and I can sleep at night knowing that I have saved some money to spend on the misses!!!!

Anyway I never know this post may help someone else

Thanks for all the replies