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EMC storage luns are not getting detected after ioscan


EMC storage luns are not getting detected after ioscan



We are using HPUX 11.31 OS and it is HP superdome2 server. we usually allocated with storage luns from EMC storage (VNX, VMAX etc), and when the storage team give us LUN id, used to do the following:


# ioscan -fnC disk

# using inq, we used to grep the LUN id, using   --- # inq -no_dots | grep "LUNID"


and as a result we will get the new agile disk names, like /dev/rdisk/disk2040. And using this disk details


for example, # ls -l /dev/disk/disk2040 - ---------------> will give us the minor, major no details.


This will be taken for the creation fo disk alias names to be used in ORACLE ASM Disk groups.


Recently we are allocated with similar type of luns, but after # ioscan -fnC disk,  the disks are not getting detected.

But in 11.23, we faced with issues like, if we run  # insf -eC disk, the raw disks which are used in ORACLE ASM permissions have changed.


So because of this issue, we afraid to run the command # insf -eC disk, followed by ioscan. But even without running insf -eC disk, we could able to detect the LUNS in the past. But now, the situation is that, the storage luns are not getting detected even the storage team is doing masking/unmasking at the storage end. In addition, we are in a thought that we could reboot the server and check for it. But this is a CRITICAL production server which is not afford for reboot.


Is the firmware of HBA has to do anything with this.


Please share your views in this regard. 





Bill Hassell
Honored Contributor

Re: EMC storage luns are not getting detected after ioscan

HP-UX doesn't see new storage automatically. That's why ioscan is required in order to query each driver which in turn queries the status of LUNs seen through the connection. But ioscan will not create any new device files.  So after new LUNs are discovered in ioscan, there won't be any device files listed in subsequent ioscan -fnCdisk.  The insf command is required to create the disk device files for new devices.


However, there is a non-intuitive option for insf: -e


The man page describes the ownership and permissions that will be set for each device, but fails to point out that it will reset *ALL* the ownership and permissions, thus destroying all previous settings. I verified this unexpected behavior on HP-UX version 10.20 as well as 11.31. I suspect this behavior is true for every version of HP-UX.


So the rule is: NEVER use -e with insf unless you want to reset ownerships *AND* permissions.

When you add new disk devices, use these commands:


ioscan -fnCdisk
insf -Cdisk


Ownerships and permissions for current devices will remain unaffected.

You can then modify the new device files as required.

Bill Hassell, sysadmin
Regular Advisor

Re: EMC storage luns are not getting detected after ioscan

Hi ,


Check syslog and if you find scsimgr replace messages , then follow the attached guide.