Environment Information : This article applies to Aruba Mobility Controllers with IP Mobility enabled.
Symptoms : In use cases , where user move from an AP to another and thereby do not retain the IP address. This article helps us to identify the Home and Foreign VLAN for an user and see if the IP mobility is functioning as expected.
Resolution :
Consider two AP's on the same controller provisioned in different AP groups . Both the groups have same SSID profile but the VLAN mapped is different . When the user roams from the first AP (AP-Group:V2 )to the second AP (AP-Group: V1) then controller marks the roaming status of the users as in Home switch/Foreign VLAN and the user retains the same IP address
1: When the user is connected to first AP, the user falls in VALN 2 (20.1.1.0)
#show user
Users
-----
IP MAC Name Role Age(d:h:m) Auth VPN link AP name Roaming Essid/Bssid/Phy Profile Forward mode Type Host Name
---------- ------------ ------ ---- ---------- ---- -------- ------- ------- --------------- ------- ------------ ---- ---------
20.1.1.2 8c:77:16:5f:da:9e authenticated 00:00:00 9c:1c:12:c2:83:9c Wireless dot1x-logon/9c:1c:12:a8:39:c0/g-HT dot1xaaa tunnel Android
#show ip mobile trail 8c:77:16:5f:da:9e
Station location trail list, 3 location(s)
------------------------------------------
9c:1c:12:c2:83:9c on switch 172.16.0.254 Station 8c:77:16:5f:da:9e
Roaming Status: Home Switch/Home VLAN, started Sat Apr 26 02:02:24 2014
Local VLAN 2, dot1x-logon/9c:1c:12:a8:39:c0/g
#show ip mobile host
Mobile Host List, 1 host(s)
---------------------------
8c:77:16:5f:da:9e
IPv4: 20.1.1.2
Roaming Status: Home Switch/Home VLAN, Service time 0 days 00:00:43
Home VLAN 2
2: When the user roams to the second AP the controller marks that user as in foreign VLAN and the ip address is retained.
#show user-table
Users
----
IP MAC Name Role Age(d:h:m) Auth VPN link AP name Roaming Essid/Bssid/Phy Profile Forward mode Type Host Name
---------- ------------ ------ ---- ---------- ---- -------- ------- ------- --------------- ------- ------------ ---- ---------
20.1.1.2 8c:77:16:5f:da:9e authenticated 00:00:01 9c:1c:12:c3:ab:f8 Foreign VLAN dot1x-logon/9c:1c:12:ba:bf:81/g-HT dot1xaaa tunnel Android
#show ip mobile trace 8c:77:16:5f:da:9e
Mobility Trace Host details
---------------------------
Station: 8c:77:16:5f:da:9e IPv4: 20.1.1.2 HA: 0.0.0.0 FA:0.0.0.0
Host Roaming Status: Home Switch/Foreign VLAN
#show ip mobile host
Mobile Host List, 1 host(s)
---------------------------
8c:77:16:5f:da:9e
IPv4: 20.1.1.2
Roaming Status: Home Switch/Foreign VLAN, Service time 0 days 00:01:40
Home VLAN 2, visiting local VLAN 1
# show datapath bridge table
Datapath Bridge Table Entries
-----------------------------
Flags: P - Permanent, D - Deny, R - Roamed Client, M - Mobile, X - Xsec, A - Auth, O - Outer VLAN, T - Trusted
MAC VLAN Assigned VLAN QinQ VLAN Destination Flags Age
----------------- ---- ------------- --------- ----------- ------- ----
8C:77:16:5F:DA:9E 2 2 0 tunnel 12 PMR 0 ---->SRC lookup,Assigned VLAN takes precedence
8C:77:16:5F:DA:9E 1 2 0 tunnel 12 PM 0 ---->DST lookup