iSCSI disk reserved - not able to bring online

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iSCSI disk reserved - not able to bring online

Postby Lionel » Sat Jul 04, 2009 8:49 am

Using Starwind 3.5.3 on Windows Storage 2003, Clustering Hyper-v with 2 servers on Windws 2008 Server.
2 iSCSI disks for 2 virtual machine on Hyper-V.
Using MS iSCSI Initiator built-in Winddows 2008 server.
A Disk from Win Storage 2k3 appear as "reserved" and can not be able to bring it online.
The other disk connected is OK.

Thanks for your reply.
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Re: iSCSI disk reserved - not able to bring online

Postby Aitor_Ibarra » Sat Jul 04, 2009 1:01 pm


I think this is by design. assuming that in Starwind you enabled clustering when you created the targets, your Hyper-V nodes are what's doing the reservation. In MIcrosoft clustering, only one node at a time can own a disk resource, so you should find that one node has the disk online and the other has it reserved. Is the cluster working OK? If it is, you should be able to quick migrate one or both of your VMs to the other node. If that works successfully, when you look at disk manager you should see that the server that was marking a disk as reserved now has it online and vice versa. Also, are you using one of the iscsi targets for both a VM and your cluster quorum? I wouldn't recommend that.... give the quorum its own iSCSI target. This can be very small; 512MB is plenty.

Hope this helps,


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Re: iSCSI disk reserved - not able to bring online

Postby Robert (staff) » Mon Jul 06, 2009 1:13 pm

What Aitor said is totally correct.

The only clarification would be that this is the way Active/passive cluster works. When something goes wrong - the passive cluster node overtakes the I/O and becomes active. When building this configuration - you would need to link the active node with StarWind iSCSI Target first, then shut the active node down (to unreserve the target) and do the same with the passive one. Once this is done, shut down the passive node and let the active node reserve the target again. After that run a Cluster validation wizard and build a cluster itself.

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