samba - May 2017 - samba-tool cannot add or remove group members

samba-tool group addmembers domaingroup 'SAMDOM\user1'
ERROR(exception): Failed to add members "SAMDOM\user1" to group
"domaingroup" - Unable to find "SAMDOM\user1". Operation
cancelled.

samba-tool group addmembers 'SAMDOM\domaingroup' 'SAMDOM\user1'
ERROR(exception): Failed to add members "SAMDOM\user1" to group
"SAMDOM\domaingroup" - Unable to find group
"SAMDOM\domaingroup"

samba-tool group addmembers localgroup 'SAMDOM\user1'
ERROR(exception): Failed to add members "SAMDOM\user1" to group
"localgroup" - Unable to find group "localgroup"

On Mon, 29 May 2017 23:01:43 +0200 (CEST)
Sébastien QUESSON via samba <samba at lists.samba.org> wrote:
> samba-tool group addmembers domaingroup 'SAMDOM\user1'
> ERROR(exception): Failed to add members "SAMDOM\user1" to group
> "domaingroup" - Unable to find "SAMDOM\user1".
Operation cancelled.
> 
> samba-tool group addmembers 'SAMDOM\domaingroup'
'SAMDOM\user1'
> ERROR(exception): Failed to add members "SAMDOM\user1" to group
> "SAMDOM\domaingroup" - Unable to find group
"SAMDOM\domaingroup"
> 
> samba-tool group addmembers localgroup 'SAMDOM\user1'
> ERROR(exception): Failed to add members "SAMDOM\user1" to group
> "localgroup" - Unable to find group "localgroup"
> 
No, I asked if you were trying it that way and if you were, to try it
the second way. 

The only way I get the error you are getting, it to try and add a user
to a group using the domain and user name e.g.

root at dc1:~# samba-tool group addmembers unixgroup "SAMDOM\suser1"
ERROR(exception): Failed to add members "SAMDOM\suser1" to group
"unixgroup" - Unable to find "SAMDOM\suser1". Operation
cancelled.
  File
"/usr/local/samba/lib/python2.7/site-packages/samba/netcmd/group.py",
line 239, in run
    add_members_operation=True)
  File "/usr/local/samba/lib/python2.7/site-packages/samba/samdb.py",
line 278, in add_remove_group_members
    raise Exception('Unable to find "%s". Operation
cancelled.' % member)

But if I do it without the domain:

root at dc1:~# samba-tool group addmembers unixgroup suser1
Added members to group unixgroup

Rowland

samba-tool group addmembers domaingroup user1
ERROR(exception): Failed to add members "user1" to group
"domaingroup" - Unable to find "user1". Operation cancelled.

samba-tool group addmembers localgroup user1
ERROR(exception): Failed to add members "user1" to group
"localgroup" - Unable to find group "localgroup"