Cloning/migrating a VM using vCenter can turn out to be quite tricky.
when you finish the ‘Clone Virtual Machine’ wizard and try to power on the new VM.
It might not start! I received this error: “Thin/TBZ disks cannot be opened in multiwriter mode”, and the new VM would not start.
After a bit of searching and fiddling around.
Right-click the VM and click ‘Edit Settings’ to bring up the Virtual Machine Properties dialog. Now change the SCSI Controller’s ‘SCSI Bus Sharing’ policy from ‘Virtual’ to ‘None’.
Now try to power on your virtual machine. It will work fine.
OR
IF you want to enable Multiwriter mode, Please follow the given steps.
Example-:
login as: root
root@192.168.10.93’s password:
Access denied
root@192.168.10.93’s password:
Last login: Fri Jun 24 12:40:03 2011 from abilochi.nivians.net
[root@ESX06 ~]# ls
ks.cfg old_cores
[root@ESX06 ~]# cd /v
var/ vmfs/ vmimages/ vmware/
[root@ESX06 ~]# cd /vm
vmfs/ vmimages/ vmware/
[root@ESX06 ~]# cd /vmfs/
[root@ESX06 vmfs]# ls
devices volumes
[root@ESX06 vmfs]# cd volumes/
[root@ESX06 volumes]# ls
4e007bf3-4d7df0f4-f367-00145e57edb0 datastore1
4e034ee1-44fe69e3-3678-0015172e90ec Datastore2
[root@ESX06 volumes]# cd datastore1/
[root@ESX06 datastore1]# ls
CLUSNODE1-STAGING iso
clusnode1-staging-176 labman
clusnode2-staging-144 VLabMan
clusstorage vmlab.iso
EN_WINDOWS_SERVER_2003_R2_ENTERPRISE_DISC1_VLP.iso W2k8clone
EN_WINDOWS_SERVER_2003_R2_ENTERPRISE_DISC2_VLP.iso Windows 2008
esxconsole-4e007a5a-9e42-df6d-a2cc-00145e57edb0
[root@ESX06 datastore1]# cd clusnode2-staging-144/
[root@ESX06 clusnode2-staging-144]# ls
clusnode2-staging-144-flat.vmdk clusnode2-staging-144.vmxf vmware-6.log
clusnode2-staging-144.nvram vmware-2.log vmware-7.log
clusnode2-staging-144.vmdk vmware-3.log vmware.log
clusnode2-staging-144.vmsd vmware-4.log
clusnode2-staging-144.vmx vmware-5.log
[root@ESX06 clusnode2-staging-144]# ls -a
. clusnode2-staging-144.vmsd vmware-4.log
.. clusnode2-staging-144.vmx vmware-5.log
clusnode2-staging-144-flat.vmdk clusnode2-staging-144.vmxf vmware-6.log
clusnode2-staging-144.nvram vmware-2.log vmware-7.log
clusnode2-staging-144.vmdk vmware-3.log vmware.log
[root@ESX06 clusnode2-staging-144]#
[root@ESX06 clusnode2-staging-144]# vmkfstools –eagerzero clusnode2-staging-144.vm
clusnode2-staging-144.vmdk clusnode2-staging-144.vmx
clusnode2-staging-144.vmsd clusnode2-staging-144.vmxf
[root@ESX06 clusnode2-staging-144]# vmkfstools –eagerzero clusnode2-staging-144.vmdk
Eagerly zeroing: 100% done.
Regards
MK
Hi,
This error will come in to picture if you are using the SCSI controller in your ESXi server as “Virtual”. So when you try to add some more disks into it it will show the following error by saying that disks cannot be added.
“Thin/TBZ disks cannot be opened in multiwriter mode.”
In such cases use the following command to create the disk in command line in ESXi Server.
(Make sure you create this disk in DATASTORE)
vmkfstools -d eagerzeroedthick -c 20G -a lsilogic DISKNAME.vmdk
The important part of this command is eagerzeroedthick without this, or using thin or zeroedthick will result in the the same error being presented at power-on of the VM.
After creating this try to add the disk ti VM host using the option “Use an existing Virtual Disk” from the datastore where you created that particular file. That fixes the above error.
Enjoy……..
Regards,
Sriharsha Kalluru.
thanks Harsha for this valuable info