(RADIATOR) Cisco, non-unique NAS-Ports, clobbering Online DB

[Dave Kitabjian]

I finally tracked down the reason why our Online DB has been reporting a
much lower count of onliners than are actually online.

Look at the attached sequence of two accounting records. tmeyers logs on
to NAS 216.118.66.25 and Port 105. Then, 3 minutes later, while he's
still online, cheezwhiz logs off of the same NAS and Port, clobbering
tmeyers' entry in the online DB. 

But how can two people have been on the same port at the same time, you
ask? The answer is that when Cisco is (again) lazy, it's easy to happen.
If you look at the Cisco-NAS-Port attribute, you'll see that they are
really on two distinct ports. Cisco is just taking a portion of the info
and plopping it in NAS-Port, even though that means that many people can
be on the same NAS-Port at once. Most manufacturers come up with a
procedure for encoding all that "Async4/105*Serial7/0:25:3" stuff into
some unique, numeric port number and then put that in NAS-Port. 

Now, if we were enforcing concurrency limits we'd be even more screwed.

Has anyone else experienced this? How are you dealing with it? Does
Radiator have any solutions? I wonder if using the Acct-Session-Id for
deletions would be more reliable than matching NAS/Port combos. Comments
welcome!

Dave
_____________________________

Wed Jul 10 15:23:21 2002: DEBUG: Packet dump:
*** Received from 216.118.66.25 port 1646 ....
Code:       Accounting-Request
Identifier: 188
Authentic:  <218><232>t<199>j<163><234><138><27><251><221><133>HsX<142>
Attributes:
        Acct-Session-Id = "000087C2"
        Framed-Protocol = PPP
        Connect-Info = "46667/24000 V90/V42bis/LAPM"
        cisco-avpair = "connect-progress=Call Up"
        Acct-Authentic = RADIUS
        Acct-Status-Type = Start
        User-Name = "tmeyers"
        Acct-Multi-Session-Id = "0000511D"
        Acct-Link-Count = "<0><0><0><2>"
        Framed-Address = 216.118.88.4
        Cisco-NAS-Port = "Async4/105*Serial7/0:25:3"
        NAS-Port = 105
        NAS-Port-Type = Async
        Class = "netcarrier.com"
        Service-Type = Framed-User
        NAS-IP-Address = 216.118.66.25
        Event-Timestamp = 1026329001
        Acct-Delay-Time = 0


Wed Jul 10 15:26:16 2002: DEBUG: Packet dump:
*** Received from 216.118.66.25 port 1646 ....
Code:       Accounting-Request
Identifier: 239
Authentic:  <30>u<226><4><138><177><143><248><254>:<165>d<182><<200>?
Attributes:
        Acct-Session-Id = "000084AB"
        Framed-Protocol = PPP
        cisco-avpair = "connect-progress=Call Up"
        Acct-Session-Time = 2897
        Connect-Info = "49333/24000 V90/V42bis/LAPM"
        Acct-Input-Octets = 349671
        Acct-Output-Octets = 2362531
        Acct-Input-Packets = 3246
        Acct-Output-Packets = 2835
        Acct-Terminate-Cause = User-Request
        cisco-avpair = "disc-cause-ext=PPP Receive Term"
        Acct-Authentic = RADIUS
        Acct-Status-Type = Stop
        User-Name = "cheezwhiz"
        Acct-Multi-Session-Id = "00004F51"
        Acct-Link-Count = "<0><0><0><1>"
        Framed-Address = 216.118.90.220
        Cisco-NAS-Port = "Async3/105*Serial7/0:18:21"
        NAS-Port = 105
        NAS-Port-Type = Async
        Class = "netcarrier.com"
        Service-Type = Framed-User
        NAS-IP-Address = 216.118.66.25
        Event-Timestamp = 1026329176
        Acct-Delay-Time = 0
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