[Kea-users] KEA 1.1.0 vs. isc-dhcp-server 4.3.3

[Ralf Hildebrandt]

* Ralf Hildebrandt <Ralf.Hildebrandt at charite.de>:

> Attached is a dump (DHCP.dump) made with 
> % tcpdump -i ens192 -vvv -s 1500 '((port 67 or port 68) and (udp[38:4] = 0x001742ef506a))' > DHCP.dump
> on the KEA server

it seems that the "Server-ID Option 54" -- set to the IP of
radius-wlan2.charite.de -- is being changed by the router
(vrf-event-roucbfpav-haus1.charite.de) to it's own IP:

	    Server-ID Option 54, length 4: radius-wlan2.charite.de
    	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
   	    Server-ID Option 54, length 4: radius-wlan2.charite.de
    	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
   	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
	    Server-ID Option 54, length 4: radius-wlan2.charite.de
    	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
    	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
	    Server-ID Option 54, length 4: radius-wlan2.charite.de
    	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
    	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de
    	    Server-ID Option 54, length 4: radius-wlan2.charite.de
    	    Server-ID Option 54, length 4: vrf-event-roucbfpav-haus1.charite.de

thus causing the 

> 2017-01-06 12:46:54.530 DEBUG [kea-dhcp4.bad-packets/10332] DHCP4_PACKET_DROP_0003 [hwtype=1 00:17:42:ef:50:6a], cid=[no info], tid=0x350ff97f, from interface ens192: it contains a foreign server identifier

mismatch

-- 
Ralf Hildebrandt                   Charite Universitätsmedizin Berlin
ralf.hildebrandt at charite.de        Campus Benjamin Franklin
http://www.charite.de              Hindenburgdamm 30, 12203 Berlin
Geschäftsbereich IT, Abt. Netzwerk fon: +49-30-450.570.155