[Samba] sites and subnets

[David Bear]

We had a samba 4.1.9 AD DC running since July. We have 3 campuses and
brought up a secondary AD  at another campus. This setup seemed to be
running as expected. We could see our primary AD DC authenticating requests
fine. We could see the secondary AD authenticating requests as well at our
second campus.

Then we started experiencing bandwidth issues between our campuses. Our
metro-etherlink should have delivered 5 mbps but dropped to have very
sporadic performance. As we worked with our telecom provider to stabilize
this, we thought we might also improve things by using the AD sites and
services tool to define where our subnets were and hopefully control which
DC handled auth requests.

About this same time we notice that DNS queries were timing out. We pointed
all DNS requests to our firewall. We forward requests for our AD domain to
our primary AD DC. This helped a lot. However we then identified our AD DC
as the problem for dns requests. It would time out frequently.

Over a couple of weeks we notices performance degrading rapidly on our AD
DC. We found samba would consume 99% cpu -- and start to grow in memory
consumption.

The big question is could the sites and services tool have triggered some
bug in samba ? So much time has elapse I don't see that it is possible to
go back and trouble shoot that way we should.

I'm just wondering if there are any known issues with sites and services --
or possible issues that could have arisen because of this tool .


-- 
David Bear
mobile: (602) 903-6476