Don't want to proxy Alive records

I am currently proxying authorization and accounting to many many
different radius servers (my customers). I have also recently set up my
NASes to send Alive accounting packets at a certain interval. These in
turn are creating Alive records in my detail files as well as proxying
this information to all of my customers servers. Only certain ones
want to get the alive information...the rest are just being bogged down
with it. I don't think it is possible, but is there a way to limit what
accounting gets proxied (i.e. not send the Alive information to certain
servers) or does freeradius just send all accounting packets along
regardless. I proxy some by dnis and others by realm.

I have been searching for this solution but can't find any answers. If
someone could point me in the right direction I would be grateful.

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