What other ways would we have of debugging this?
On Thu, Feb 8, 2024 at 5:39?PM Douglas Bagnall <
douglas.bagnall at catalyst.net.nz> wrote:
> On 9/02/24 06:35, Elias Pereira wrote:
> > for i in $(seq 1 10); do time /usr/sbin/samba_kcc --debug; sleep
> 5;done
> >
> > I ran the command and in one run it lasted more than 2 minutes.
> >
> > I've sent you the file if you'd like to take a look.
>
> To summarise for the list, one of the runs took 3 minutes, and the rest of
> them
> took half a second.
>
> $ grep -A2 real Downloads/kcc_output.txt
> real 2m59.646s
> user 0m0.387s
> sys 0m0.163s
> --
> real 0m0.504s
> user 0m0.413s
> sys 0m0.078s
> --
> real 0m0.496s
> user 0m0.371s
> sys 0m0.112s
> --
> [...]
>
> The debug output of each run is identical.
>
> Looking at the 'user' and 'sys' lines, we can see that
samba_kcc wasn't
> doing
> anything extra in those 3 minutes. It was just waiting. For what, I
don't
> know.
>
> Douglas
>
>
>
> >
> > On Wed, Feb 7, 2024 at 8:03?PM Douglas Bagnall <
> douglas.bagnall at catalyst.net.nz
> > <mailto:douglas.bagnall at catalyst.net.nz>> wrote:
> >
> > On 8/02/24 11:17, Elias Pereira wrote:
> > > Hi Douglas, thanks for the answer!!!
> > >
> > > samba kcc command = /path/to/samba_kcc --debug
> > >
> > >
> > > I ran the command and the result is in the pastebin below,
if you
> can
> > > take a look.
> > > https://pastebin.com/x6W2yWm7
<https://pastebin.com/x6W2yWm7>
> > <https://pastebin.com/x6W2yWm7
<https://pastebin.com/x6W2yWm7>>
> >
> > It looks to me like that was a successful run, but I can't see
if it
> was
> > slow.
> >
> > If I understand correctly, sometimes it is bad, and sometimes it
is
> not.
> > If you run in a loop, something like
> >
> > for i in $(seq 1 10); do time /usr/sbin/samba_kcc --debug; sleep
> 5;done
> >
> > then you might find one that takes more than 40 seconds -- that is
> the
> > NT_STATUS_IO_TIMEOUT.
> >
> > Douglas
> >
> >
> > >
> > > But anyway, I don't think this is a samba_kcc
specific
> problem, and
> > > https://bugzilla.samba.org/show_bug.cgi?id=15568
> > <https://bugzilla.samba.org/show_bug.cgi?id=15568>
> > > <https://bugzilla.samba.org/show_bug.cgi?id=15568
> > <https://bugzilla.samba.org/show_bug.cgi?id=15568>>is due
to the
> same
> > > underlying issue. I don't know what that is.
> > >
> > >
> > > I opened this bug, but no one has replied yet.
> > >
> > > >> UpdateRefs failed with NT_STATUS_IO_TIMEOUT
> > > This is a different replication failure, independent of
the
> KCC.
> > > samba_kcc works out where the DC should replicate from,
and
> the drepl
> > > code does the actual replication.
> > > Both could fail with network weirdness, or if either the
> local or remote
> > > database is locked up for some reason.
> > >
> > >
> > > And how can I debug this problem? I've searched
everywhere and
> found
> > > nothing about it.
> > >
> > > On Wed, Feb 7, 2024 at 6:40?PM Douglas Bagnall
> > > <douglas.bagnall at catalyst.net.nz <mailto:
> douglas.bagnall at catalyst.net.nz>
> > > <mailto:douglas.bagnall at catalyst.net.nz
> > <mailto:douglas.bagnall at catalyst.net.nz>>> wrote:
> > >
> > > On 8/02/24 02:11, Elias Pereira via samba wrote:
> > > > Any idea how I can debug this?
> > >
> > >
> > > >>> I don't know the answer to that, but I
think setting
> > > >>>
> > > >>> samba kcc command =
/usr/sbin/samba_kcc -d5
> > > >>>
> > >
> > > I looked it up. Actually
> > >
> > > samba kcc command = /path/to/samba_kcc --debug
> > >
> > > *might* produce more interesting results (you'll
probably
> want to use
> > > `less -R` to view the logs).
> > >
> > > You can run samba_kcc independently -- it should not do
any
> harm, but
> > > you can use the --readonly flag if you want to be
careful.
> > >
> > > But anyway, I don't think this is a samba_kcc
specific
> problem, and
> > > https://bugzilla.samba.org/show_bug.cgi?id=15568
> > <https://bugzilla.samba.org/show_bug.cgi?id=15568>
> > > <https://bugzilla.samba.org/show_bug.cgi?id=15568
> > <https://bugzilla.samba.org/show_bug.cgi?id=15568>>
> > > is due to the same underlying issue. I don't know
what that
> is.
> > >
> > > >> [2024/02/02 20:05:17.752322, 0]
> > > >>
> > >
> >
>
../../source4/dsdb/repl/drepl_out_helpers.c:1300(dreplsrv_update_refs_done)
> > > >> UpdateRefs failed with NT_STATUS_IO_TIMEOUT
> > >
> > > This is a different replication failure, independent of
the
> KCC.
> > >
> > > samba_kcc works out where the DC should replicate from,
and
> the drepl
> > > code does the actual replication.
> > >
> > > Both could fail with network weirdness, or if either the
> local or
> > > remote
> > > database is locked up for some reason.
> > >
> > > >> What does this part of the code do?
> > > >> source4/dsdb/kcc/kcc_periodic.c:790
> > >
> > > That just reports that samba_kcc failed.
> > >
> > > cheers,
> > > Douglas
> > >
> > >
> > >
> > > --
> > > Elias Pereira
> >
> >
> >
> > --
> > Elias Pereira
>
>
--
Elias Pereira