Issue with rlm_replicate and retransmissions

[Brian Candler]

I have found some odd behaviour to do with proxying and retransmissions with
rlm_replicate (specifically accounting packets)

I set up a proxy config, where I also happen to modify the packet.

preacct {
    ...
    Proxy-To-Realm := "handover"
    ...
    update request {
        Reply-Message += "foo"
    }
}

As well as proxying, rlm_replicate is used to feed the accounting packets
elsewhere:

accounting {
    sql_log
    ...
    replicate    # using rlm_replicate and Replicate-To-Realm
}

Now, if the "handover" home servers are down, and I send a test packet with
retransmissions using

echo -e 'User-Name="briantest"\nEvent-Timestamp=1342099825\nFramed-IP-Address=1.2.3.4\nAcct-Status-Type=Interim-Update' |
  radclient -r3 -t3 -x localhost:1813 acct testing123

what I find is:

* just the first packet is written to the sql_log (that's fine)
* For the second and third packets, freeradius -X just shows
    "Discarding duplicate request from client localhost port 36957 - ID: 146"
  After that, freeradius says
    "Rejecting request 0 (proxy Id 181) due to lack of any response from home server 192.0.2.1 port 1813"
* all three packets are replicated. The second and third replica packets are
  missing the Reply-Message attribute

It's this last bit which I think is odd. Shouldn't the replicate also be
suppressed for retransmissions?  Or if not, shouldn't it at least process
the packet in the same way?

Regards,

Brian.