identify hostname

Pete Kruckenberg pete at
Wed Dec 2 00:26:18 UTC 1998

On Tue, 1 Dec 1998, Dean Anderson wrote:

> You don't need a tool. People already have provisioning/configuration tools
> or are doing it by hand.  Whichever is the case, just add a rule to your
> customers interface. You know when you configure the interface what the
> mask is and what the broadcast is.  All you need to do is add an access
> list entry which applies to that customers interface.

That works fine as long as you either manage your customers' equipment or
your customers don't subnet blocks you give them. However, in real-world
experience, neither of those apply, especially to a larger ISP/NSP (UUNet
was mentioned in this thread at the beginning).

It certainly doesn't hurt to put in access-list's where you can, to reduce
the problem, but that is not a scalable solution. It is an incredible
management nightmare, especially if you're having to keep track of
autonomous customer routing changes. Not to mention that it adds to the
burden of tracking down problems (imagine a DHCP server which assignes
what used to be a broadcast address, but is no longer because the subnets
were combined, and everytime a machine gets that address, it can't get
outside the network because the administrator hasn't updated the
5,000-line access-list).


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