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Sean_Kane
Enthusiast
Enthusiast

Adding existing VMFS LUN

Hi Everyone,

Current Setup:

Clariion SAN

ESX 3.5 Cluster

ESX 3.0.2 Update 1 Cluster

I have an existing LUN which currently has VM's installed and running on that LUN. Basically, I want another ESX server to get access to this LUN. I feel like a moron and it seems like this process should be straightforward.

I have added a new ESX Server (3.0.2) to the appropriate storage group so that it can gain shared access to the LUN with other ESX servers. On the new server, I went into the Storage Adapters and performed a "Rescan" which now shows the new LUN in the list of LUNs.

The next step is tripping me up, I feel like I should be going into Storage and clicking "Add Storage" however the "Warning: The current disk layout will be destroyed. All file systems and data will be lost permanently" message which is making me nervous.

How do I go about adding an existing VMFS LUN to a new ESX server? Also, just an additional piece of info, the LUN I am adding, was created with an ESX 3.5 server.

Thanks in advance,

Sean

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8 Replies
VMKR9
Expert
Expert

You should go to the storage tab and just click refresh, you do not have to add the storage again

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Sean_Kane
Enthusiast
Enthusiast

I saw that in another thread - so I did another rescan and refresh. It has already shown up in the Storage Adapters area... but a refresh of the Storage list does not make the new datastore available.

Thanks!

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demz
Expert
Expert

If you add storage, it will be asked to format the new partition.

Just click on the refresh link Smiley Happy

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demz
Expert
Expert

Oh really ?

That's strange.

Did you try a classic service mgmt-vmware restart ?

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Sean_Kane
Enthusiast
Enthusiast

Nope - I didn't try that yet. If I run that command, will it disrupt the VM's currently running on that particular host?

Another thought that crossed my mind... The host I am adding this LUN to is configured for HA with another ESX host. However, I did not add the LUN to the other ESX host. Should I be adding the LUN to that host as well for the datastore to appear? Now that I think it through... it kind of makes sense.

Thanks!

Sean

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demz
Expert
Expert

Yeah in fact that make sense, but I think the LUN should be shown in the LUN list when you refresh...

You can try that.

(no service mgmt-vmware restart just restart some services and re-read the esx.conf file, it just lose connectivity for few seconds with the ESX and its VMs)

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dmaster
VMware Employee
VMware Employee

Hi Sean_Kane,

Some brand of ESX servers needs sometimes a reboot after adding existing storage.

Can you try doing a reboot of the ESX host.

If still nothing is visible it can be that there is something wrong with the signature on the disk.

you can write a new siganture on the vmfs datastore with preserving the data on that datastore.

Goto Advanced Settings --> LVM --> LVM.EnableResignature --> change the value from 0 --> 1

rescan your storage (storage adapters section)

Goto Advanced Settings --> LVM --> LVM.EnableResignature --> change the value from 1 --> 0

changeback to the original datastore name

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VMKR9
Expert
Expert

You need to be carefull but I have seen a similar problem before and changing the advanced setting LVM, lvmDisallowSnapshotLun and then rescan may fix the problem

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