Do you know what the SAN policy of your disks is now?

If you run

DISKPART> SAN

it will return the current policy. Can you post the result here?

I think it will be something like

SAN Policy : Offline Shared

In this case, I believe you’re looking for a way to put it as OnlineAll. You can do

SAN POLICY=OnlineAll

But please beware:

SAN policy has been introduced in Windows Server 2008 to protect shared disks accessed by multiple servers. The first time the server sees the disk, it’ll be offline, but after being brought online once, should be online even after reboot.

You can use POLICY=OnlineAll setting to get around this, but it must be very clear that if the disks are shared among servers, this can lead to data corruption. Users are encouraged to use the proper SAN policy to protect data.

Hope it helps!