Biggest installation of ISC DHCP?

David W. Hankins David_Hankins at
Mon Jan 21 15:57:02 UTC 2008

On Sat, Jan 19, 2008 at 12:54:08PM +1100, Nick Urbanik wrote:
> One thing that I would do now instead of the "next file" solution to
> the hourly restarting problem is to simply have the server write its
> leases to a DB file.  That way it would remain at a constant size and
> wouldn't need aggregating or restarting.  Startup time is a

not entirely constant size; lease structures themselves change size

so all db's need some kind of vacuuming eventually to reclaim
fragments...when a lease grows larger it gets shuffled elsewhere in
most DB's and leaves a hole...just a question of how long between
vacuums (or if it's longer than the system's lifetime of service).

the main advantage in startup time for a lease db that is not log
structured is not having to replay the log; every lease is only
processed once even with fragments.

> This LDAP patch simply extends the expression language to look up
> things from LDAP.  We use it to look up customers' MAC addresses.  It
> does not read the configuration from LDAP.  We read the configuration
> from /etc/dhcpd.conf.

hm, the one i'd heard of two years ago wanted to put lease state into
LDAP along with config.

it sounded more of a full replacement.

this is actually better as it's a smaller change; we can always push
into the other areas incrementally.

> We are also using a DHCPLEASEQUERY patch.

...which we've already got thanks to Shane's review of a submitted
patch (can't remember the author's name).

you're possibly using the same patch as we based ours off of.

> I need to determine the origin of the LDAP expression patch.  We use
> no additional proprietary libraries.


David W. Hankins	"If you don't do it right the first time,
Software Engineer		you'll just have to do it again."
Internet Systems Consortium, Inc.	-- Jack T. Hankins

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