[Samba] Time outs and high cpu usage after upgrading to 4.12.11

[Rowland penny]

On 28/02/2021 10:21, Sebastian Lisic via samba wrote:
> Hi,
>
> I recently upgraded two Centos 8 domain controllers from 4.11.15 to 4.12.11 and am now getting periodic issues with high cpu usage and io time outs every other day. Restarting Samba temporarily fixes the problem for another day or so.


What packages are you using, or did you build Samba yourself ?

>
> Replication works fine before the problem manifests and after I restart Samba.
>
> I am seeing the following errors in log.samba on DC1:
>
>
> [2021/02/27 13:20:44.283975,  0] ../../source4/rpc_server/common/forward.c:51(dcesrv_irpc_forward_callback)
>
>    IRPC callback failed for DsReplicaSync - NT_STATUS_IO_TIMEOUT
>
> [2021/02/27 16:52:08.011225,  0] ../../source4/dsdb/dns/dns_update.c:86(dnsupdate_nameupdate_done)
>
>    dnsupdate_nameupdate_done: Failed DNS update with exit code 110
>
> [2021/02/27 19:57:52.397404,  0] ../../source4/dsdb/kcc/kcc_periodic.c:768(samba_kcc_done)
>
>    ../../source4/dsdb/kcc/kcc_periodic.c:768: Failed samba_kcc - NT_STATUS_IO_TIMEOUT
>
> [2021/02/27 20:02:52.551916,  0] ../../source4/dsdb/kcc/kcc_periodic.c:768(samba_kcc_done)
>
>    ../../source4/dsdb/kcc/kcc_periodic.c:768: Failed samba_kcc - NT_STATUS_IO_TIMEOUT
>
> During the same day I am seeing the following errors in log.samba on DC2:
>
>
> [2021/02/26 17:58:42.117403,  0] ../../source4/dsdb/repl/drepl_out_helpers.c:1301(dreplsrv_update_refs_done)
>
>    UpdateRefs failed with NT_STATUS_IO_TIMEOUT
>
> [2021/02/26 18:08:53.563593,  0] ../../source4/dsdb/repl/drepl_out_helpers.c:1301(dreplsrv_update_refs_done)
>
>    UpdateRefs failed with NT_STATUS_IO_TIMEOUT
>
> [2021/02/27 22:58:39.993614,  0] ../../source4/dsdb/repl/drepl_out_helpers.c:1301(dreplsrv_update_refs_done)
>
>    UpdateRefs failed with NT_STATUS_IO_TIMEOUT
>
> [2021/02/27 23:08:47.766855,  0] ../../source4/dsdb/repl/drepl_out_helpers.c:1301(dreplsrv_update_refs_done)
>
>    UpdateRefs failed with NT_STATUS_IO_TIMEOUT
>
> [2021/02/27 23:29:17.597409,  0] ../../source4/dsdb/repl/drepl_out_helpers.c:1301(dreplsrv_update_refs_done)
>
>    UpdateRefs failed with NT_STATUS_IO_TIMEOUT
>
> [2021/02/27 23:58:38.307600,  0] ../../source4/dsdb/repl/drepl_out_helpers.c:1301(dreplsrv_update_refs_done)
>
>    UpdateRefs failed with NT_STATUS_IO_TIMEOUT
>
There doesn't seem to be a correlational between the times, is it 
possible that there is a time problem ?

Rowland