reindexing the ioconfig file

[skt_skt]

The OS limit for ext_bus instances is stored as a two bit hex value SCSI_MAX_BUS_ID and thus is limited to 255. There is not a workaround to
access devices on bus instances above 255 and the fix is implementation of the SCSI-3 which is available from HP-UX 11.31 onwards
The work around is reconfiguring the /etc/ioconfig & /stand/ioconfig by freeing up the unused instances which requires a reboot. We have created the new config which holds 99 instances against the 256 in the old config.
adedd75n:root [/home/kumarts] grep ext_bus io.old|wc -l
256
adedd75n:root [/home/kumarts] grep ext_bus io.new |wc -l
99

i have recreated the ioconfig file using a utlity provided by HP which checks the ioscan and picks which ever ext_bus instances are in use and skips the unused one..

Did any one try this practically? let me know your feedback. I am conserned about the ctd numbers which is very critical to the cluster..

[Sandy Chen]

Hi,

I've done the ioconfig tools from HP once, on a cluster environment. But we did that because of changes of instance number, which causing a different ctd number.

You should keep your old ioconfig file so that you can revert back to your old configuration.

Good luck with this :)

Regards,
Sandy

[skt_skt]

" But we did that because of changes of instance number, which causing a different ctd number"

Could u tell your scenario a little more..
I am expecting the problem of ctd number change. In your case u r tring to fix thc ctd change. You mean u were asighing a aprticular instance number to a ext_bus?

[Joel Shank]

I have tried this and it works. The original instance numbers did not change. I too was concerned that this might occur, but it did not. All went very smoothly. However, keep a backup copy of your original ioconfig file just in case.

jls

[Eric SAUBIGNAC · Accepted solution]

Bonjour,

I did not know that there is a special HP Tool for that.

Here is the procedure I follow when I want to change instance numbers (Never tested with 11iv3). In your case you don't want to change instance number, so just skip step 2 in this procedure :

1. ioscan -kf | grep -e INTERFACE -e DEVICE | grep -v target | awk '{printf "%s %s %s\n",$3,$1,$2}' > /stand/infile

2. [ Just skip step 2 ] vi /stand/infile and modify instance numbers. Example :

8/0 ext_bus 0
8/4 ext_bus 3

==> Modify as :

8/0 ext_bus 3
8/4 ext_bus 0

3. Save ioconfig files :

mv /stand/ioconfig /stand/ioconfig.sav
mv /etc/ioconfig /etc/ioconfig.sav

4. shutdown -ry 0

5. From the console, stop boot process and boot in single mode :

hpux -is (under PA-RISC)
boot vmunix -is (under Itanium)

6. The system starts witn an "ioinitrc" prompt. Create ioconfig file :

cd /stand
/sbin/ioinit -c

7. update it with infile (This command will also reboot the system) :

/sbin/ioinit -f infile -r

ioconfig files will be cleaned.

Regards

Eric

[skt_skt]

this tool excellent. it free up the unused ext_bus instances .

Also the /dev/rscsi/ get updated too. No manual cleanup required

[skt_skt]

this tool excellent. it free up the unused ext_bus instances .