Access-Accept BUT no connection

[Clement Ogedengbe]

I have posted this before and the response I got was "If the server sends an Access-Accept and the user doesn't get online....blame the NAS. Always".

I am having a situation where the connection just broke without any config change. We have two alternate RADIUS servers (Main one and a back up) both receiving packets from the same NAS.

I returned to the office after the week end to find users are not getting online in spite of the Main RADIUS server returning Access-Accept (This has always been working and there has been no config change on the NAS and Radius servers).

I changed the same NAS to connect to the Backup RADIUS server and everything works. I can't figure out how NAS is to blame here please!  

Below is the extract of post-authentication reply log from the Main RADIUS server to the NAS, but users are not getting online.

10.255.253.2 Returned from 193.62.48.61 for User xxxx - Tue Jan 28 09:51:57 2014
        Packet-Type = Access-Accept
        MS-CHAP2-Success = 0x00533d44303538334343433436373339323643313033343843413135463643373637333639373241423130
        MS-MPPE-Recv-Key = 0xc4c255e279235d1abc4128569b4391b6
        MS-MPPE-Send-Key = 0x3773e3518d6620d5d8f85e158848c601
        MS-MPPE-Encryption-Policy = 0x00000002
        MS-MPPE-Encryption-Types = 0x00000004

Many Thanks

Clement