VMWare giving: ['ERROR: not a valid btrfs filesystem: /dev/disk/by-id/sda3', '']


I´m trying out rockstor in Vmware and getting following error:

Error running a command. cmd = [’/sbin/btrfs’, ‘filesystem’, ‘show’, ‘/dev/disk/by-id/sda3’]. rc = 1. stdout = [’’]. stderr = [‘ERROR: not a valid btrfs filesystem: /dev/disk/by-id/sda3’, ‘’]

 Traceback (most recent call last):

File “/opt/rockstor/src/rockstor/rest_framework_custom/generic_view.py”, line 40, in _handle_exception
File “/opt/rockstor/src/rockstor/storageadmin/views/disk.py”, line 272, in post
return self._update_disk_state()
File “/opt/rockstor/eggs/Django-1.8.16-py2.7.egg/django/utils/decorators.py”, line 145, in inner
return func(*args, **kwargs)
File “/opt/rockstor/src/rockstor/storageadmin/views/disk.py”, line 218, in _update_disk_state
p.uuid = btrfs_uuid(dob.name)
File “/opt/rockstor/src/rockstor/fs/btrfs.py”, line 985, in btrfs_uuid
[BTRFS, ‘filesystem’, ‘show’, ‘/dev/disk/by-id/%s’ % disk])
File “/opt/rockstor/src/rockstor/system/osi.py”, line 109, in run_command
raise CommandException(cmd, out, err, rc)
CommandException: Error running a command. cmd = [’/sbin/btrfs’, ‘filesystem’, ‘show’, ‘/dev/disk/by-id/sda3’]. rc = 1. stdout = [’’]. stderr = [‘ERROR: not a valid btrfs filesystem: /dev/disk/by-id/sda3’, ‘’]

no matter what disk settings I use…

@unomagan Hello again.

For this you will need to ensure that your vmware has allocated a unique serial to all Rockstor drives, in this case it’s the system drive that is affected but they must all have a unique serial in order that Rockstor can track them. All real drives meet this criteria but unfortunately not all virtual ones do. We have a pending documentation issue to address this in our Minimum system requirements section of the official docs:

Hope that helps. The Vmware docs should help to address this short fall and allow for the possibility for Rockstor to accurately track disks even when they have no file system on.

Thanks! found it! While the error is very very misleading though…

For anyone interested:


added / Edited in the VMX file of the VM


I suggest providing a downloadable vmware appliance as an alternative. I just ran in this problem and it gave me a very bad impression of the product

Agreed. This seems likely to affect all esxi users.

There is a gui method to change that parameter here:


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