Difference between Received conflicting packet and Ignoring duplicate packet

[norbert.kunth at now-it.de]

Hi Freeradius-Users,

we recently updated from 2.1.1 to 3.0.25 (we use still 3.0.25 because it 
is build in our SLES distribution).

Freeradius uses LDAP to check users. If many users login at a time we see 
some error messages.

To track this down we installed an internal test system that can send a 
lot of requests to the radius server (with radtest).

We do see some problems, but the messages (and the behavior) are not the 
same.

If we fire 60 requests in a short time from the test system to the 
servers, the server loggs:
Thu Nov  3 13:35:11 2022 : Error: (159) Ignoring duplicate packet from 
client test port 46673 - ID: 65 due to unfinished request in component 
<core> module <queue>

This seems not very bad: every user is still accepted via LDAP

But in real the message is different:
Thu Nov  3 00:59:25 2022 : Error: Received conflicting packet from client 
nas port 40634 - ID: 90 due to unfinished request in module ldap.  Giving 
up on old request.
Thu Nov  3 00:59:25 2022 : WARNING: (338542) WARNING: Module rlm_ldap 
became unblocked
Thu Nov  3 00:59:25 2022 : Auth: (338542) Invalid user: [user024] (from 
client nas port 0)

We think, we have a timing issue with our LDAP. But why is the log message 
so different?

Best regards
Norbert
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