Adding SCSI drive 2

[slingsby]

Hi,

We are running a old DELL 4400 series machine running 'SCO open server 5.0.6' this currently has two raid partitions.

1. System disc <mirror> (two drives)
2. Data disc <Raid-5> (three drives)

I have now plugged a new SCSI 73Gig drive into the 6th slot on the front of the machine.

At boot time I see three volumes and their sizes reported by the controller, Mirror, Raid-5 and Legacy.

I would like to use mkdev hd to allow me to use this new disc (without raid).

I now need the correct parameters to add the drive.


The two existing volumes as defined in 'hwconfig'

are:

name=disk vec=- dma=- type=S ha=0 id=0 lun=0 bus=0 ht=percraid
name=disk vec=- dma=- type=S ha=0 id=1 lun=0 bus=0 ht=percraid

so use the percraid drivers.

I assume that I should not be using this driver as the drive is non raid.

The Dell documentation describes the SCSI controllers:

"SCSI devices: an internal SCSI backplane provides a physical connection,
hot-plug capability with RAID controller, termination,
and automatic configuration for the internal SCSI hard-disk drives;
an integrated Adaptec Ultra 160/m AIC-7899 SCSI host adapter
supporting up to ten SCSI hard-disk drives depending on the installed backplane"

My uncerainties:

1. Should I try the 'blad' driver choosing id=5 (sixth drive). The mkdev hd host adaptor (h) list only describes blad as supporting the 7890 and 7897 chip sets (not 7899).
2. If I try this rebuild the kernal and the system fails to boot, will I be able to recover by booting the unix.old kernel.
3. Is unix.old automatically created after a rebuild.
4. How would I delete the disk definition created by mkdev for subsequnt rebuilds of kernel.

Thank you for looking at my problem, any advice welcome,

Thanks,

Peter

 

[Annihilannic]

Even though it is a single drive it should still be presented to the OS as a logical volume by the PERC, so the configuration process on the operating system side should be more-or-less identical to the existing volumes.

Annihilannic.

 

[stanhubble]

as annihilannic says just use id=2 when doing the mkdev hd.


name=disk vec=- dma=- type=S ha=0 id=2 lun=0 bus=0 ht=percraid

 

[slingsby]

A Big thanks to Annihilannic and Stanhubble for their input.
I will certainly try out this suggestion. Before I try out anything like this on a live system I always like to have a regression plan. As adding the extra drive will require a kernal rebuild I assume that I will need to boot unix.old at startup. However I can not find any documentation on the removal of the newly added drive i.e. the reverse of 'mkdev hd' so that if kernal is subsequently rebuilt then the build does not include the new drive. I know this is a little fussy but this would make me a little more relaxed about attempting this.

Thanks.

 

[stanhubble]

mkdev hd
or
mkdev .scsi
will give you the option to remove a device as well as adding one. just make sure you get the ha,id,lun combination correct.

 

[slingsby]

Hi,

I have been lookong at the SCO command mkdev but have not as yet managed to find the switches to remove a drive (when incorrectly defined or removed). I have looked in the MAN pages and found no reference to deletion or removal.
I would have thought that this was not an unreasonable thing to expect to achieve!

Peter

 

[stanhubble]

sorry been a long time since i ran mkdev hd.....

use mkdev .scsi instead

 

[slingsby]

Thanks stanhubble,

That is what I was missing mkdev .scsi gives options:

1. Add a SCSI device
2. Remove a SCSI device
3. Display current SCSI configuration
4. Display SCSI help message

So removal of unwanted SCSI devices is option 2!

I ran option 3 and saw the following output:

-------------------
The configuration file currently has entries for the following devices:

Host
Adapter Adapter
Type Device Number ID LUN Busmkdev
-------------------------------------------
alad cd-rom 0 5 0 0
percraid disk 0 0 0 0
percraid disk 1 1 0 0
percraid disk 0 1 0 0
ad160 tape 0 14 0 0

Press any key to continue:
--------------------

It appears that I probably already have one erroneous 'percraid' entry as I only have two volumes.

As I don't have have a disk on adaptor 1

name=disk vec=- dma=- type=S ha=0 id=0 lun=0 bus=0 ht=percraid
name=disk vec=- dma=- type=S ha=0 id=1 lun=0 bus=0 ht=percraid

Can I assume that "percraid disk 1 1 0 0" is a spurious entry?

From this observation it appears that spurious entries are not going to cause a startup problem and will just be ignored.
So it appears that the addition of an extra volume should not cause too much of a problem at startup if additional settings
were to be added incorrectly.

Are there any flaws in my reasoning?

Thanks,

Peter

 

[slingsby]

Hi,

I have now competed the disc install using the percraid controller worked well,

Thanks