Re: [Netdisco] Display List of Status changes per node

[Brian De W. <br...@bl...>]

On Thu, 28 Oct 2010 17:47:36 +0300
Nikolaos Milas <nm...@ad...> wrote:

> If the system/database doesn't keep enough data to produce such reports, 
> could it be extended with a patch or some additional script? The report 
> could be generated with a direct database query, provided enough 
> information is included therein to produce the report.

The results of a node search on the webpage are surprisingly
representative of the data present in the database, actually.  The
tables only store a first and last time seen for a given ARP
relationship (MAC, IP), so when that relationship is seen again, the
last seen time is updated to the current time.

So, unfortunately, if you try to use it for user tracking in an area
with lots of transitory machines (wireless with low lease times is a
good example), the data is almost entirely useless.  The design itself
is understandable, though, as it keeps storage costs from shooting
through the roof.


Using the existing front-end might be difficult if you try to patch in
recording every data point.  The existing tables are keyed on (mac, ip)
so you won't be able to insert rows for multiple times for a given pair.
I would expect the front-end to make assumptions about the existence of
only one entry for each (mac, ip) pair as well.  Making arpnip record
to a new table, or to text files, would be easy enough, though.
Unfortunately, I'd expect performance on that table to slowly nose dive,
as it would experience constant growth on every arpnip run.


In our environment, we usually fall back to correlating IP usage with
our DHCP logs.  Those are usually pretty clear about who had the lease
at any given time.  I just pretend no one is spoofing IPs...