How to debug "Got POOLREQ, answering negatively"?

[sthaug at nethelp.no]

> My thinking lately has been for the peer (sending the POOLREQ) to
> also provide one of the addresses in the pool it thinks is misbalanced
> enough to generate the response.  The receiving server could use the
> address to find the pool, and would only balance this one pool in this
> case.  We could also lift the restriction that the server only send
> one POOLREQ at a time (now you could send 5 for the 5 specific pools
> you care about).  It sounds like we could add the peer's
> active/free/backup statistics for logging purposes.

Sounds like a good solution to me.

> I'm also debating if we should take more stringent action on a
> negative answer to a POOLREQ.  Something like taking a trip through
> potential-conflict, but this worries me.  This could self-heal db
> inconsistencies (which has the unfortunate side effect that we'd
> probably stop hearing about db inconsistency bugs).

How about an option which defaults to *logging* info to identify
the inconstency, but which can be explicitly configured to also
self-heal? If you want to be clever, make it configurable only by
OMAPI, so you know it is turned off next time the dhcpd process is
restarted.

And while I'm in wishlist mode - it would be great to have a document
which specifies *exactly* what is necessary for two lease files, one
from the primary and one from the secondary, to be consistent.

> And so long as we're talking, it would be great for there to be
> some way other than the hex-printed address in memory of the pool
> structure to uniquely name a pool.  :(

Absolutely. But as long as the actual IP address is logged together
with the hex address in "balancing pool"/"balanced pool" messages,
I can live with the hex addresses.

> For the time being, I think you should be able to check the peer's
> logfile, as its balance run entry for the pool in question will
> indicate its desire to request rebalance (I think it logs this even
> if multiple pools want to send POOLREQ...I think it appends
> "requesting pool rebalance!" or something).

Yes, that's how I verified I was on to the right pool, after I had
identified it through other means.

Steinar Haug, Nethelp consulting, sthaug at nethelp.no