[Samba] Samba keeps crashing when in AD mode due to mitkdc exiting.

[Rowland Penny]

On Mon, 2022-06-06 at 07:00 -0700, Matthew Schumacher via samba wrote:
> Hello All,
> 
> I have a number of samba servers acting like RODC controllers and
> every 
> few days samba exits because the MIT KDC Daemon dies with exit status
> 11:
> 
> [2022/06/04 21:14:29.561323,  0] 
> ../../source4/dsdb/kcc/scavenge_dns_records.c:523(dns_delete_tombston
> es)
>    dns_delete_tombstones: Failed to delete dns node
>    kccsrv_dns_zone_tombstone_deletion: DNS tombstone deletion
> failed: 
> NT_STATUS_INTERNAL_ERRORkccsrv_periodic_run: 
> kccsrv_dns_zone_tombstone_scavenging failed -
> NT_STATUS_INTERNAL_ERROR
> : Address family not supported by protocol The MIT KDC daemon died
> with 
> exit status 11
> : Address family not supported by protocol task_server_terminate: 
> task_server_terminate: [mitkdc child process exited]
> [2022/06/05 20:18:54.520080,  0] 
> ../../source4/samba/server.c:391(samba_terminate)
>    samba_terminate: samba_terminate of samba 714: mitkdc child
> process 
> exited
> 
> in the mit_kdc.log I see:
> 
> Jun 05 20:18:54 host.ad.domain.net krb5kdc[753](info): TGS_REQ (5
> etypes 
> {aes256-cts-hmac-sha1-96(18), aes128-cts-hmac-sha1-96(17), 
> DEPRECATED:arcfour-hmac(23), DEPRECATED:arcfour-hmac-exp(24), 
> UNSUPPORTED:(-135)}) 172.23.77.6: PROCESS_TGS: authtime 0, etypes 
> {rep=UNSUPPORTED:(0)} <unknown client> for 
> krbtgt/ad.domain.net at ad.domain.net, No matching key in entry
> Jun 05 20:18:54 host.ad.domain.net krb5kdc[753](info): closing down
> fd 21
> 
> I'm using samba-4.16.1 and krb5-1.19.3.  Any thoughts on how to
> debug 
> this issue so that I can report a bug to at least keep it running?
> 
> I can compile an alternate kerberos daemon and rebuild samba against
> it, 
> but it's my understanding that AD mode only works with MIT kerberos.
> 
> schu

You might want to read this:
https://wiki.samba.org/index.php/Running_a_Samba_AD_DC_with_MIT_Kerberos_KDC

Where you will find that using MIT is classed as experimental and
running Samba with MIT as an RODC isn't supported.

Rowland