sys job sends warnings for each DRBD device file

The sys job (/usr/share/backupninja/sys) will grab all device files but zram files

if [ "$partitions" == "yes" ]; then
   if [ "$dosfdisk" == "yes" ]; then
      devices=`LC_ALL=C $LSBLK --output NAME,TYPE --list --paths 2>/dev/null | grep "disk$" | grep -v '^/dev/zram' | /usr/bin/awk '{print $1}'`

In a machine where DRBD is used, there is a bunch of /dev/drbd* device files.

But, these devices files will never have any partition table, they only distribute a block device, which is where the partitions rest.

root@weloveriseup0:/# lsblk | grep -A1 "data-12345678990--1234--4567--9876--asdfghjkl.disk0_meta"
      ├─data-12345678990--1234--4567--9876--asdfghjkl.disk0_meta 253:5    0   128M  0 lvm   
      │ └─drbd0                                                  147:0    0   246G  1 disk  
--
      ├─data-12345678990--1234--4567--9876--asdfghjkl.disk0_meta 253:5    0   128M  0 lvm   
      │ └─drbd0                                                  147:0    0   246G  1 disk  

If feel like we should add an or in the grep -v part of the command that build the device list. For exemple

if [ "$partitions" == "yes" ]; then
   if [ "$dosfdisk" == "yes" ]; then
      devices=`LC_ALL=C $LSBLK --output NAME,TYPE --list --paths 2>/dev/null | grep "disk$" | grep -v '^/dev/zram\|^/dev/drbd' | /usr/bin/awk '{print $1}'````

Do you see any problem with this approach?