Only one response so far, and I am happy with the explanation.
Thank you to Christopher Davis for the response below.
The emx (fiberchannel host adapter) driver dynamically assigns SCSI IDs
to devices when they're first seen. In your case, it saw the D100-D199
controller first, so it got the lower SCSI ID. (See the emx(7) and
emx_data.c(4) man pages for more details.)
You can override the automatic assignments by editing emx_data.c and
rebuilding the kernel. This is critical in a TruCluster setup as
otherwise the hosts may have different addresses for the same disks;
in a non-TruCluster environment, it's just cosmetic.
The file /etc/emx.info has a "human-readable" (by contrast with
/etc/emx.db, anyway) form of the address assignment information,
suitable for editing into emx_data.c.
> Also if I had named a unit as D99 , what would that have become ?
Invisible to that host (the SCSI-emulation only shows you the first 8
LUNs per ID). However, if you used the UNIT_OFFSET parameter, you could
have a different host see D99 as a disk device.
-----Original Message-----
From: bboddy - Bill Boddy [mailto:BBODDY_at_acxiom.co.uk]
Sent: Tuesday, December 14, 1999 10:38 AM
To: Tru64 Unix Managers
Subject: HSG80 - special device names
Last weekend I upgraded a pair of HSZ70's for HSG80's.
It all went fine ( no loss of data ) except ...
Before the upgrade I had on the HSZ70's the following storage ...
All RAIDsets are 6 member RAID 5.
RAID Set name Unit Name What Unix sees the device as
R1 D0 rz8
R2 D100 rz9
R3 D200 rz10
R4 D300 rz11
After the upgrade they became the following.... ( I couldn't keep the same
Unit numbers
because the HSG80's support unit numbers from d0 - d199 only )
R1 D0 rz9
R2 D100 rz8
R3 D1 rzb9
R4 D101 rzb8
Therefore as you can see , I can't seem to grasp the logic of why D0 became
rz9 ( i.e. doesn't fit the algorythm
of 8 x BUS number + SCSI ID number ) etc.
Also if I had named a unit as D99 , what would that have become ?
Bill Boddy
Unix System Administrator
Acxiom Ltd.
0191 525 7348
bboddy_at_acxiom.co.uk
Received on Tue Dec 14 1999 - 15:34:43 NZDT