[TEST][PATCH] Replication errors with Samba4

[Andrew Bartlett]

On Tue, 2012-07-31 at 08:04 +0200, Stefan (metze) Metzmacher wrote:
> Hi Andrew,
> 
> >> In my repl-devel branch I have a series of patches to better test our
> >> replication and conflict resolution handling.
> >>
> >> https://git.samba.org/?p=abartlet/samba.git/.git;a=shortlog;h=refs/heads/repl-devel
> >>
> >> Currently we have a number of issues in this area.  The test I added
> >> there shows that we do not consistently handle the conflict resolution.
> >> This is particularly the case with conflicting renamed. 
> >>
> >> The attempts at modification of the replication code I've included try
> >> to handle some of this, but it still doesn't work.  
> >>
> >> However, this code remains dizzyingly complex, and I wondered if,
> >> particularly as I now have a reasonable testsuite, you might be able toa
> >> assist me in making this more reliable?
> > 
> > I've found some of the issues here, but I still can't make the conflict
> > handling reliable.  I've put in the test simply asserting that one or
> > other record becomes a conflict, until we can get back to this.  It
> > would be very helpful to me if you could look at this area, as this
> > should be deterministic :-(.
> > 
> > Still, at least is no longer stops or crashes. 
> 
> Does it randomly fail make test (if so what's the test name?)
> or do you see the strange behavior in normal operation?

What happens is that the additional tests I added in
samba4.drs.replica_sync.python fail randomly.  

To get the rest of the patch into mater (and to ensure we have any
coverage of this codepath at all), I've modified the tests to accept
that one DN or the other is made into a conflict, but not to assert on
which one in particular is the conflict.   This is in autobuild now. 

On that branch, It is clear that it's random because if you run it
twice, the line number (corresponding to unit tests) of the assertions
changes. 

Once these are in master, I'll update that branch with just the stricter
test. 

Andrew Bartlett

-- 
Andrew Bartlett                                http://samba.org/~abartlet/
Authentication Developer, Samba Team           http://samba.org