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LUNs presented from a CLARiiON array to a host are read only

Knowledgebase Solution   

Environment:  Product: CLARiiON
Environment:  EMC SW: Navisphere Manager
Environment:  EMC SW: Replication Manager
Problem:  LUNs are read only when allocated to a host from Navisphere.
Problem:  LUNs presented to host are read only.
Change:  Customer added the LUN to a Storage Group from Navisphere.
Root Cause:  When a Replication Manager job runs, it leaves attributes on a LUN. If the LUN is mounted again using Replication Manager, will be correctly presented to the host. If the LUN is mounted using Navisphere, the attributes are not cleared and may present problems to hosts accessing the LUNs. 

Fix:  Follow these steps:
Run c:diskpart
DISKPART> select disk 4

(Select the appropriate disk, which in this case is 4.)
 
DISKPART> detail disk

PowerDevice by PowerPath
Disk ID: 9F0B09CD
Type : FIBRE
Bus : 0
Target : 1
LUN ID : 3

Volume ### Ltr Label Fs Type Size Status Info
———- — ———– —– ———- ——- ——— ——–
Volume 5 M SQL 2005 MD NTFS Partition 10 GB Healthy
 
Verify the Disk ID is set correctly. Note the Volume number as well and use it in the following command:

DISKPART> select volume 5
DISKPART> detail volume

Disk ### Status Size Free Dyn Gpt
——– ———- ——- ——- — —
* Disk 4 Online 10 GB 0 B

Readonly : Yes
Hidden : No
No Default Drive Letter : Yes
Shadow Copy : Yes
 
If any of the Read Only, Hidden, or No Default drive letters are set to Yes, clear them with the follow command:

DISKPART> att vol clear readonly hidden nodefaultdriveletter

Volume attributes cleared successfully.
DISKPART>exit
 
Notes:  The att vol clear readonly hidden nodefaultdriveletter command clears the attributes set for the LUN presented under Windows.
Notes:  Drive needed to be rescanned in Device Manager before it was represented to the host.
Notes:  The LUNs should be added to a Storage Group using Replication Manager.

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