Hello everyone, we have a ubuntu 14.04 with freeradius 2.1.12+dfsg-1.2ubuntu8.1 configured to use Active Directory to do authentication (using winbind and ntlm_auth), eap, pap and mschap. Weekly the freeradius is restarted (with a signal HUP) by logrotate and usually it works fine. But sometimes MSCHAP authentication stop working after the restart (both plain with radtest and with PEAP from wireless client) while PAP continues working. We can detect the problem running `radtest -t pap ...` (it works) and `radtest -t mschap ...` (it doesn't). The response we get is:
rad_recv: Access-Reject packet from host 127.0.0.1 port 1812, id=204, length=38 MS-CHAP-Error = "\000E=691 R=1"
and the log says:
Login incorrect (mschap: External script says )
Restarting the freeradius solves the problem (with service freeradius restart). I'm unable to reproduce it (it just happens sometimes, like once every two months) and I can't get a debug log with `freeradius -X` because restarting solves the problem. I've been able to log the parameters passed to the external program ntlm_auth that are:
--request-nt-key --username=someuser --challenge=00 --nt-response=00 --domain=OUR_DOMAIN
the configuration is:
ntlm_auth = "/usr/bin/ntlm_auth --request-nt-key --username=%{reply:AD-Samaccountname} --challenge=%{%{mschap:Challenge}:-00} --nt-response=%{%{mschap:NT-Response}:-00} --domain=OUR_DOMAIN"
so I think that for some reason the mschap module brokes down and stops putting the right values in the dictionary. I noticed that this (for now) happened only with weekly logrotate restarts and not with manual restarts (when I update the configuration). Another thing I noticed is that it happens only at the primary radius server (~500k authentications every week, some local and some proxied) and not on the secondary (~40k authentications every week, basically just monitoring). The two radius server share the same configuration (as in "I copied the files") and software version. Any hint in how to debug it? (or resolve it) Thanks for reading my mail and for any help you could provide. Regards, Enrico Polesel