[Samba] ERROR: Transfer of 'pdc' role failed: Failed FSMO transfer: WERR_GEN_FAILURE

[Matthias Leopold]

Hi,

I transferred FSMO roles between two DCs for the first time (in the 
course of version upgrade from 4.12 to 4.13 including DC demote). I did 
it twice (once transferring to 4.13 from 4.12, once between all 4.13). 
In both cases I got an error when transferring the PDC role:

# samba-tool fsmo transfer --role=pdc
ERROR: Transfer of 'pdc' role failed: Failed FSMO transfer: WERR_GEN_FAILURE

The transfer actually seems to succeed (when checking "samba-tool fsmo 
show" afterwards). In logs of "losing" DC I see:

[2021/01/22 14:30:44.080710,  0] 
../../source4/rpc_server/drsuapi/getncchanges.c:1413(getncchanges_change_master)
   ../../source4/rpc_server/drsuapi/getncchanges.c:1413: FSMO role or 
RID manager transfer owner request when not role owner

I'm not 100% sure this is from PDC role transfer, could theoretically 
also be from other (succeeding) transfers.

Samba packages are from Sernet, OS is CentOS 8.

Why is this? Do I have to worry?

thx
Matthias