howto get rid of NO_HW?

[DuKul]

Hello all,
I have the server with two FC adapters (HP Tachyon XL2). There has been the SAN switches change.
After the change some FCP Domain devices stayed in NO_HW (I think these items in ioscan output represents the old switches...) Everything is working well, but I would like to get rid of the NO_HW status in ioscan output without reboot.
These items (FCP Domain) have no special files associated, only FC adapter have.
My idea is to use rmsf to remove the special file and HW information for one of the FC adapters with all his children and then recreate the special files and HW info again with inssf. I suppose that the data will flow through the second FC adapter so no data flow interruption will be observed....
I have never done such a sequence before, neither I am sure about this idea, so that is why I am asking for your opinion/experience whether or not it would help.
Best regards
Dusan

[siva0123]

Hi,

insf -e
ioscan -fn

Should help you.

Thanks,
Siva

[DuKul]

Hi Shiva,
I doubt that because the insf -e would help because it only reinstalls the special files if some of them were removed and they are there.
But the switches mentioned are NOT there.

[Torsten.]

Hi,

2 possibilities:

1) reboot the server

2) perform a "rmsf -k -H" followed by the hw-path of the removed devices

[SANTOSH S. MHASKAR]

Hi,

Yes u can remove the device files using rmsf,

first probe for devices

# ioscan -fn|more

note the HW_PATH of items having NO_HW state.

then

# rmsf -H


u can create device files for newly probed
devices.

# insf -e


TO get the rid of NO_HW u have to reboot the system.


-Santosh

[DuKul]

Please,
as I have already written:
- the FCP Domain interface has NO special file so it CANNOT be removed using -H option

The question is about the idea written above...
DuKul

[Denver Osborn]

As Torsten replied, you have two options. Either reboot or "rmsf -k -H "

"rmsf -k -H" does not remove device special files, it removes the definition of the devices attached to the hw patch from the system... so you wouldn't see it in ioscan.

This doesn't remove all devices, but you can try it before you decide to reboot.

-denver

[DuKul]

For example
# rmsf -v -k -H 0/4/0/0.7.17.255.0
rmsf: Specified hardware path has no devices

This command would be successful only if the HW would have its special file. So this lead me again to only one possibility how to remove those ugly children - to rmsf its parent = the FC adapter which has the special file:

fc 0 0/4/0/0 td CLAIMED INTERFACE HP Tachyon XL2 Fibre Channel Mass Storage Adapter
/dev/td0


And my question is whether or not would be such an approach safe (because I suppose the data flow will continue using the second FC adapter).....
...or if such an approach would even lead to removing the HW information of its ugly children.

DuKul

[Denver Osborn]

It depends on how your volume manager was setup and if you have any mutlipathing product installed...

If you have LVM configured with PV Links, then it shouldn't be a problem. However, there's no need to do this. If you run rmsf -k -H , then it will remove all devices attached to that HBA _except_ for things like fcp domain, fcp array, and ext_bus. Those won't be removed. You'd have to reboot the box to clean those up. It will remove disk, target and ctl class devices. Which you've probably already done.

You can post your ioscan output as an attachment if you want us to look it over.

-denver

[DuKul]

Hi Denver,
no, it is no need to put an ioscan output.
I would like to remove exactly the items fcp domain and ext_bus, which you are staying that they cannot be removed....and I do not like the reboot....
DuKul

[DuKul]

Hi Denver,
no, it is no need to put an ioscan output.
I would like to remove exactly the items fcp domain and ext_bus - you are staying that they cannot be removed....and I do not like the reboot....
DuKul

[Denver Osborn]

That's correct, you won't be able to remove those. The ioscan output is as clean as it's going to get without a reboot.

There shouldn't be any harm in having them on the box until you have a scheduled outage. Worst case scenerio is you may see an EMS alert from that device which could be ignored or put into ems' disabled instances.

-denver

[DuKul]

Hi Denver,
that's clear....
However, I hoped to have the procedure to clean out the NO_HW from ioscan. I do not know why it is principially impossible.
DuKul

[Jacob Alexander]

Use this script... it works for me

#!/usr/bin/ksh
# Script Name : clean_NO_HW_path.sh
# Author : Alexander Jacob
# Description : This script collects data with ioscan and executes rmsf
# cleans-up NO_HW path
################################################################
/sbin/ioscan -fn > /tmp/ioscan.out
d=$(date "+%Y%M%d%H%M")
echo "Cleaning NO_HW path devices with chk_NO_HW_path.sh script at `date`"
echo "Verify status in /var/tmp/chk_NO_HW_path.log.${d}"
echo "It will take time, pl. wait....."
(echo "Cleaning NO_HW path devices with chk_NO_HW_path.sh script at `date`"
echo -----------------------------------------------------------------
echo
egrep 'disk|dsk' /tmp/ioscan.out|while read a
do
if echo $a|grep disk > /dev/null
then
echo "$a \c"
else
echo "$a"
fi
done|grep NO_HW|awk '{print $9,$3,$0}'|while read d h o
do
echo $o
if echo $o|grep GGC >/dev/null
then
grep "$d" /var/tmp/avail_clar.out
else
grep "$d" /var/tmp/avail3.out
fi
grep "$d" /var/tmp/powermtdisp.out
#echo $o
echo "rmsf -H $h "
/usr/sbin/rmsf -H $h
done
echo "Cleanup of NO_HW path process completed at `date`"
echo "--------------------------------------------------"
) > /var/tmp/chk_NO_HW_path.log.${d} 2>&1 &

[Sp4admin]

Hello,

Just run the "insf -e" command and then try your ioscan command again.

sp,

[Geoff Wild]

As sad as it brings me to say this, I have seen NO_HW remain even after the rmsf -H

Have you rebooted since the san change? (that's the sad part)

I had to do that once whne we had a san change and it cleared up the NO_HW

Rgds...Geoff

[DuKul]

Jacob - the script deals only with disks, which is not my case....
Geoff - no, I have not rebooted - I would like to avoid it, or - let's say - I had to avoid it.
Anyway, thanks to all with relevant answers....
It seems that this really could not be done without reboot under HP-UX.

[feeble]

I know this is an old thread, but I just ran into this issue. We are on 11.31 and using the multipathing. In our case we could not see a newly presented disk. I thought it was an NO_HW fcp issue. Anyway, I used rmsf -H on the actual fc's, not the fcp and it cleared up my issue. It did not remove the NO_HW for the fcp's, but I was then able to see the disk. Hope this helps someone in the future.

[Torsten.]

for 11.31 try

rmsf -x