host-identifier and option 82

Christian Kratzer ck-lists at
Mon Jan 30 21:08:48 UTC 2012


On Mon, 30 Jan 2012, Alex Moen wrote:
>> I don't see that much of a need for concatenations of multiple identiers 
>> currently as you could always just put all you need in one string.  I do 
>> see a need to support multiple different host-ids in one ldap tree. Like 
>> for example circuit-id for some hosts and subscriber-id for others.
> I am not sure what you mean by this statement.  For instance, we (another 
> ISP) use agent-circuit-id, agent-remote-id, and vendor-class-identifier on 
> almost all of our networks, utilizing "The old hack of having a class and 
> small single ip pool per port" as you put it.  It makes for a very long, 
> slow-loading config.  If you can give me an example of how to create a host 
> entry using all three of those identifiers, I would be very appreciative.  If 
> that does not work, then your statement that there is no need is false...  :)

the point I was trying to make was that every port is unique and instead
of having the touple of agent-circuit-id, agent-remote-id being unique
why not just use a string with a globally unique circuit-id and ignore
the remote-id.

If you leave circuit-id as the locally unique port description you need
the remote-id to make it globally unique.

If you put something unique as astring into circuit-id you can get by
with just the circuit-id.

Of course not all gear will support string as circuit-id and there can
be other reasons to require a more general matching.

The first and immediate target is getting the ldap code for dynamic lookups
on par with what is currently implemented in the static configuration.

For the setups I have in mind the effort of configuring a unique
cicruit-id is by far lover than the effort needed to get matching
on multiple options.  Especially as the lookup is very much different
when searching the in memory database in one case and ldap in the
other case.

The general case is certainly not impossible. It just needs a bit more effort
in both design and implementation.


Christian Kratzer                      CK Software GmbH
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