Changing the disk device instance number using ioinit

[Karthik S S]

Hi All,

I have a A-Class server that is connected to a EVA5000 and has 3 LUNs presented from the EVA.

------------
disk 7 255/255/1/0.0 sdisk CLAIMED DEVICE HSV110 (C)COMPAQ
/dev/dsk/c21t0d0 /dev/rdsk/c21t0d0
disk 8 255/255/1/0.1 sdisk CLAIMED DEVICE HSV110 (C)COMPAQ
/dev/dsk/c21t0d1 /dev/rdsk/c21t0d1
disk 9 255/255/1/0.2 sdisk CLAIMED DEVICE HSV110 (C)COMPAQ
/dev/dsk/c21t0d2 /dev/rdsk/c21t0d2

-----------------

I want to change the /dev/(r)dsk/c21txdx to /dev(r)dsk/c11xtxdx for the above three LUNs. How do I do it?? Here with I am attaching the infile and ioscan output.

Kindly let me know what changes needs to be done to the attached infile.

Thanks,
Karthik S S

[Karthik S S]

Attaching ioinit and ioscan -fn outputs.

Thanks,
Karthik S S

[Sridhar Bhaskarla · Accepted solution]

Hi Karthik,

It's the ext_bus that you would need to change as the controller number is associated with the ext_bus. So, I would configure your infile as

255/255/1 ext_bus 11

Try 'ioinit -f infile' and see if you get any errors. If not, then reboot the system to get the things changed. It's most likely that the instance 11 might already have been registered in your ioconfig file. If it gives out errors that the instance 11 is already assigned and if it is absolutely necessary for you to use c11 for these disks, then you will have to prepare an ioinit file under / with the syntax "hardware class instance" for all the devices you don't want the device files to change and the devices for which you want the device files to change. Shutdown your application. Move /stand/ioconfig and /etc/ioconfig as ioconfig.old in their respective directories and reboot the system. The system will come into ioinitrc# prompt. Run "/sbin/ioinit -c" to create ioconfig file with default instance numbers. Overwrite it with your desired configuration by running "/sbin/ioinit -f in_file -r" command. The system will reboot and come up with the instance numbers you wanted.

Remember that it can be quite dangerous if you don't pay attention. For ex., network instance numbers may get changed as well your root disks. So, be prepared. Generate map files for all the VGs and store them on the network. Create make_tape|net_recovery tapes. Ofcourse you can get the old configuration back by moving ioconfig.old files into place but a human is a human. I would attemp this procedure if and only if it is absolutely necessary.

-Sri

[Karthik S S]

Hi Sridhar,

Thanks for those steps.

Do you mean only the line,
255/255/1 ext_bus 21

should be changed to,
255/255/1 ext_bus 11

and no more changes to the infile??

Pl. clarify.

I will be careful and take a backup before proceeding with this.

Thanks,
Karthik S S

[Sridhar Bhaskarla]

Hi Karthik,

Yes. However, there is a good chance that it may not succeed. I was always successful in going from lower instance number to higher than the other way. Going from higher instance to lower is not guaranteed. In this case, you will need to follow the other procedure.

-Sri

[T G Manikandan]

check this http://www2.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000072080614

make sure you have two or three ignite tape copies before proceeding.

[Turlough McKeown]

Can someone PLEASE give reference to the mentioned document for the European site? Following the link goes to US site.

Thanks