Moving HP-UX boot disk between RX1620 & RX4640

[ALCS]

Hi,

I need to know how successful to move an HP-UX boot disk from an RX4640 to an RX1620 and still be able to boot w/o problems.

As you can see I'm trying to know if the RX1620 can be used on a temporarily basis instead of an RX4640 in case this last one fails.

feedback and suggestions are very well appreciated.

The system will be connected to an EVA for an add on storage.

Regards,
Farid

[Eric Lemmers]

This is not as straight forward as it seems. What you need to know is whether or not the root disk remains itâ s device file.
The rx1620 has the device files /dev/dsk/c2t0d0 and /dev/dsk/c2t1d0 for the two internal disks. I donâ t know the exact device files of the internal disks for a rx4640.

If the device files are not the same on the two systems very hard / impossible to boot the system from it.

Eric

[Alan_152]

It isn't going to be very easy, unless you (1) reconfigure to boot from the EVA instead of virtual storage, and (2) can modify the boot manager conf files in /boot/efi to accomodate the different boot device interconnects between the two models.

You'd have much better luck if your backup machine was a 2620.

[ALCS]

Thank you Guys for your contribution
I will keep monitoring for further feedbacks.
Boot from the EVA seems to be an option but

Do you believe the system disk will be fine booting when it detects a different hardware (for instance 4 CPU with 4640, then 2 CPU with the 1620)

Regards,
Farid

[Eric Lemmers]

Farid,

Once you have solved the problem with the device path's the OS image will probably boot without a problem. Additional processors is not a problem for the kernel.

You also mentioned you are thinking about booting from SAN. If you are trying to switch the Boot-LUN from one system to the other, you have to look at the device issue.

I think the only working solution will be two systems with the fiber adapters on the same IO path( in this situation 0/2/1 and 0/3/1)
IO pathing of the two systems are:
rx4640 IOpath
0/2/1
0/3/1
0/3/2
0/4/1
0/4/2
0/5/1

rx1620 IOpath
0/2/1
0/3/1

Regards,

Eric

[ALCS]

Thank you Eric for your time
I will let you know how it goes
once the hardware is ready (probably needs some time)

Regards,
Farid

[Sandy Chen]

Hi Farid,

The hardware path for rx4640 and rx1620 is slightly different,

for rx1620:
0/1/1/0.0.0 /dev/dsk/c2t0d0
0/1/1/0.1.0 /dev/dsk/c2t1d0

for rx4640:
0/1/1/0.1.0 /dev/dsk/c2t1d0
0/1/1/1.0.0 /dev/dsk/c3t0d0

if you are using disk with the same hardware path, I believe it will not be a problem.

The hardware changes such as cpu, memory etc will not be an issue.

regards,
Sandy

[ALCS]

Thank you Sandy for your feedback
As I can see one path is common: 0/1/1/0.1.0 /dev/dsk/c2t1d0

Do you think it will work in case of system disk mirroring where two common)paths are needed ?

Thanks,
Farid

[Eric Lemmers]

Farid,

It will probably not recognize it's mirror, while it does not recognize it's device path in the configuration files, but if you specify the boot command as hpux -lq there is a good chance it will work.

Best way probably to do this is to put only one bootdisk in the rx1620. When you're done with the rx1620 and move the bootdisk to the rx4640 again, some mirrors will be stale and must be re-synchronized...

Eric

[ALCS]

Thanks Eric
I believe we are well prepared now
Many thanks for all

Best regards,
Farid