Configuring Freeradius to keep a local copy of accounting records and send a copy to a remote server

[Frank Godek]

Hi Everyone,

I've used Radius for many, many years but have not had to worry about the
accounting records until now.  I have a client that is going to provide
authentication for a remote partner organization.  They will be billing them
based on both having their clients connect and also, to some extent, on how
much data the partner's clients use.  The remote partner needs to get
accounting records in order for them to make payment.  At the same time, my
client wants copies of the records so they can verify that they are getting
paid correctly.  I setup a new FreeRadius server for this purpose so I'm
running 3.0.17 on Ubuntu 16.04.

In the wireless APs that are providing service, I can easily set two
accounting servers but, as has been the case since I started using Radius,
the secondary server is a fallback for the primary not a location where
duplicate entries are sent.

I have tried setting up a realm that points to the remote partner and to use
the copy-acct-to-home-server module.  That worked great as far as sending
the records to the remote partner but I could see that what it was doing was
renaming the details file, transferring the contents of that file to the
remote server, and then deleting the renamed details file. Of course, that
left me without details on the local server.

So, what's the best and/or easiest way for me to keep a copy locally?  Do I
need to define a virtual server and setup a home-server-pool with the remote
server?  I looked at that but it seemed that the home-server-pools were
either setup for either load balancing or failover.  I don't want either.  I
want a copy of every record to stay local AND be sent to the remote server.

Thank you in advance for your help.  I've been reading through the docs and
also online examples but haven't found much that was very clear on this
setup.

Frank Godek