sracharla
3 Silver

LUN discovery on RHEL4

Hi everyone,

I have LUNs provisoned from VNX to Oracle RAC servers running RHEL4 OS. The new luns are not seen, I have checked using fdisk -l

I have run the hba scan command

echo"- - - " > /sys/class/fc_host/hostX/scan but of no use,

I found a Qlogic HBA discovery script on the Qlogic website 'ql-dynamic-tgt-lun-disc.sh' ,

I have not used this before, Can this be used while there is production IO running?

It is giving a warning as below when trying to run

please make sure there is no active I/O when running the script below..

Any suggestions using this script ?

Thanks


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10 Replies
dynamox
7 Thorium

Re: LUN discovery on RHEL4

Does this host have LUNs from this VNX or this is a brand new provisioning ?

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sracharla
3 Silver

Re: LUN discovery on RHEL4

This host has already 19 LUNs provisioned to it.

I just added additional 3 50GB LUNs to the storage group.


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sracharla
3 Silver

Re: LUN discovery on RHEL4

I noticed that the powerpath version is also 5.3 which is EOL.

But I don't think that will a problem for the host to see the volumes

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dynamox
7 Thorium

Re: LUN discovery on RHEL4

yeah, i don't think it has anything to do with PowerPath.  Have you tried this sequence of commands:

echo "1" > /sys/class/fc_host/hostX/issue_lip

echo "- - -" > /sys/class/scsi_host/hostX/scan

echo "1" > /sys/class/fc_host/hostX/issue_lip

echo "- - -" > /sys/class/scsi_host/hostX/scan

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sracharla
3 Silver

Re: LUN discovery on RHEL4

Tried only the second command
echo "- - -" > /sys/class/scsi_host/hostX/scan

for the first one, there is no fc_host folder under /sys/class,

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dynamox
7 Thorium

Re: LUN discovery on RHEL4

can you cat that bash script. What commands does it run ?

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sracharla
3 Silver

Re: LUN discovery on RHEL4

It has many funtions included in the script, to find HBAs, disocver all targets, LUNs...

I think they are qlogic specific commands


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dynamox
7 Thorium

Re: LUN discovery on RHEL4

reason i ask because back back in the old day they would want you to unload qlogic HBA drivers to discover new LUNs, very disruptive.

Roger_Wu
5 Rhenium

Re: LUN discovery on RHEL4

echo "- - -" > /sys/class/scsi_host/hostX/scan always works for me.

If not, then reboot the host...

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