Re: GSSAPI and LVS Load balanced ldap servers

[Aaron Richton <richton@nbcs.rutgers.edu>]

On Tue, 3 Feb 2009, Francis Swasey wrote:

> failure mode.  It works with ldaps://ldap.uvm.edu and fails with 
> ldaps://<realname>.uvm.edu.  Which is "OK" for my purposes.
>
> I'd really like to be able to have both work, but perhaps cyrus-sasl will 
> change at some point in the future to support the kind of trickery that 
> really happens out here in the world.

I'm not so sure I agree with this. In theory, when you're doing load 
balancing through a VIP, all the real servers should appear absolutely 
identical. You don't *want* the clients to be able to see which real 
they're getting. If one of them processes requests as rs1 and a different 
one doesn't...that's a failure of the load balancing configuration, IMO.

With that said, I'll of course note that in practice, theory and practice 
don't always agree. But it looks like they do in this case, and I can't 
see what the negative would be.


[maybeHint: Around here, the reals know who they are individually, but 
slapd is only configured as the VIP and the VIP name is aliased in 
/etc/hosts. So we can check end-to-end authentication locally on each 
real, and it shows up on Nagios appropriately, in the event that one of 
them gets confused. MOST IMPORTANTLY, this is exactly the same as the USER 
experience, because we're NOT monitoring "ldap://rs1/"; -- that's not what 
users care about!]