OBP - root / mirror disk syntax

Hi all

Can someone explain to me the different syntax regarding how root / mirror disks are represented. I never truely understand the namely / device tress etc.

Let me give you an example. On one my my servers, the root and mirror drives are :-

A domain on a sunfire 6800 :-
devalias vx-rootdisk /ssm@0,0/pci@1a,700000/pci@1/SUNW,isptwo@4/sd@0,0:a
devalias vx-rootmirror /ssm@0,0/pci@1a,700000/pci@1/SUNW,isptwo@4/sd@1,0:a

On another server, a v880 the root / mirror drives are :-

devalias sds-mirror /pci@8,600000/SUNW,qlc@2/fp@0,0/disk@1,0
devalias sds-disk /pci@8,600000/SUNW,qlc@2/fp@0,0/disk@0,0

On another server, a 280, the root / mirror are :-

nvramrc=devalias mirror /devices/pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w500000e010bfd1d1,0:a

i.e. some have :a or :b or :c on the end of the device path. Why's this ? Is it hardware related ? when it says disk0,0 Im assuming its disk 0, slice 0 ?

How come the dfference in naming ?? This always gets me, and Ive never really truely known why this is.

Cheers

You should attend the Sun Support Readiness Training , where the instructor will teach you more in depth.
Initial Program Load: How Solaris disk device names work

yes it depends on the hardware.

now, disk@0,0 (or sd@0,0) (sd = scsi disk) doesn't mean disk 0 slice 0

it means t0d0

disk@1,0 means t1d0

and so forth...

now the meaning of "a", "b", "c"...it means the slice

so c0t0d0s0 should be: disk@0,0:a

now, by default, if you don't specify the slice number it will take slice zero.

for example:
disk@0,0 means t0d0s0

disk@0,0:a means also t0d0s0

disk@0,0:f = t0d0s5

disk@1,0:b = t1d0s1

..............................

Now, the rest of the device name depends on the hardware, but there are things in common, take this example of yours:

/devices/pci@8,600000/SUNW,qlc@4/fp@0,0/ssd@w500000e010bfd1d1,0:a

Explanation:

pci@8,60000 = your system bus address
SUNW,qlc = the driver for QLogic card (for example, Emulex cards will look like this SUNW,emlx)...

fp@0,0 = means it's a fiber channel

ssd@w500000e010bfd1d1,0:a = WWN number is w500000e010bfd...

1,0:a = (as you already know) t1, slice 0

.....

all these things are documented by the way...you can go to each server's page in the system handbook, and check the hardware components and then go to the system board section, you should find more in-depth explanations.

so yes it depends on the hardware and the architecture of the system.

---------- Post updated at 01:23 AM ---------- Previous update was at 01:20 AM ----------

And by the way, you can do this to find out your system details:

For example:

# ls -l /dev/rdsk/c0t0d0s0

it should show you a link to the actual hardware

Thanks Sunfire. Your explanation was great. Its always been something Ive wondered.

So, the :a is optional ? Or depending on hardware it is or isnt ?

SBK

you can say "a" is optional..because if you don't supply the slice number it will take slice 0 by default (which is "a").

Good luck

sunfire, last questions.

I understand now that ssd@0,0 is t / d of cxtxdx :a or b or c is the sx part. When I do a luxadm probe on the disk, what does the raw bit mean ?

E.G

/devices/pci@1,700000/SUNW,qlc@0,1/fp@0,0/ssd@w203500a0b8117594,0:c,raw

SBK

It means that you're looking at the raw physical device itself...and this address is not to be used for booting. The device we use for booting is a link to the one you just printed.