[Samba] Can't use DNS Manager in MMC on Samba 4.12.0

[Alex MacCuish]

On Samba 4.12.0, I receive the error "ndr_pull_uint32: 
ndr_pull_error(Buffer Size Error): Pull bytes 4 
(../../librpc/ndr/ndr_basic.c:152) at ../../librpc/ndr/ndr_basic.c:152" 
when opening the DNS Manager in MMC.

This jumped out at me from the log-level 10 output (I'm happy to send 
the full logs but would rather do that somewhere more private):

/dnsserver: Found DNS zone xxx.xxx.xxx//
//ndr_pull_uint32: ndr_pull_error(Buffer Size Error): Pull bytes 4 
(../../librpc/ndr/ndr_basic.c:152) at ../../librpc/ndr/ndr_basic.c:152//
//     DnssrvComplexOperation2: struct DnssrvComplexOperation2//
//        out: struct DnssrvComplexOperation2//
//            pdwTypeOut               : *//
//                pdwTypeOut               : DNSSRV_TYPEID_NULL (0)//
//            ppDataOut                : *//
//                ppDataOut                : union DNSSRV_RPC_UNION(case 
0)//
//                Null                     : NULL//
//            result                   : WERR_DNS_ERROR_DS_UNAVAILABLE//
//Sealed 16 bytes, and got 76 bytes header/signature.//
//dcerpc_pull_auth_trailer: auth_pad_length 0//
//Unsealed 112 bytes, with 76 bytes header/signature.//
//     DnssrvComplexOperation2: struct DnssrvComplexOperation2//
//        in: struct DnssrvComplexOperation2//
//            dwClientVersion          : DNS_CLIENT_VERSION_LONGHORN 
(458752)//
//            dwSettingFlags           : 0x00000000 (0)//
//            pwszServerName           : *//
//                pwszServerName           : 'xxx.xxx.xxx.xxx'//
//            pszZone                  : NULL//
//            pszOperation             : *//
//                pszOperation             : 'EnumZones'//
//            dwTypeIn                 : DNSSRV_TYPEID_DWORD (1)//
//            pDataIn                  : union DNSSRV_RPC_UNION(case 1)//
//            Dword                    : 0x00000013 (19)/


I'm thinking the DNS RPC server isn't running:

samba-tool dns serverinfo dc01:

/Failed to connect host xxx.xxx.xxx.xxx on port 135 - 
NT_STATUS_CONNECTION_REFUSED/

/Failed to connect host xxx.xxx.xxx.xxx (dc01) on port 135 - 
NT_STATUS_CONNECTION_REFUSED./

/ERROR: Connecting to DNS RPC server dc01 failed with (3221226038, 'The 
transport-connection attempt was refused by the remote system.')/

Anyone have any ideas on how I can get the DNS RPC server up and running 
again? I notice also in the bind9 logs that it prints the normal "found 
zone xxx" message but doesn't list all my zones. I have also opened a 
bug (14310)