RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Description of problem:
Creation of VDO device ontop of DRBD is not possible as follows:

Creating VDO vdodrbd0
vdo: ERROR -   Device /dev/drbd0 excluded by a filter.

As the DRBD Technology is closer to RAID1 (but over a network connection) , I expect that the VDO should be a layer above drbd.

Version-Release number of selected component (if applicable):
kmod-kvdo-6.1.0.153-15.el7.x86_64
vdo-6.1.0.149-16.x86_64


How reproducible:
Always

Steps to Reproduce:
1.Create a 2 node drbd device
2.Try to create vdo ontop:
# vdo create --name=vdodrbd0 --device=/dev/drbd0 --vdoLogicalSize=10G

Actual results:
Received error "vdo: ERROR -   Device /dev/drbd0 excluded by a filter."

Expected results:
VDO to be successfully created on top of DRBD.

Additional info:

VDO uses come some helpful code from lvm to test block devices
This could be one of two problems:

1. This device was already part of a LVM physical volume in some way and LVM is
catching that fact.  Clearing out that metadata could help.

2. or you need to add a filter to the lvm.conf file to include drbd devices, similar to this  add "filter = [ "a|drbd0.*|", "r|.*|" ]".

As my DRBD device is blacklisted via a global filter, I will try without that filter.

Shouldn't that be listed somewhere in the documentation ,as I checked the whole documentation and I didn't find any relevant configuration file /I should have straced the process to find that/ ?

It would be way easier if there is a statement like:
"VDO uses some portions of LVM , thus /etc/lvm/lvm.conf should be taken into consideration."

VDO documentation states that LVM is required, however it doesn't say why.  

Created a bug to update the documentation.

https://bugzilla.redhat.com/show_bug.cgi?id=1581741

Closing documentation will be updated.