Controller Based WLANs

Q:

SNMP trap to notify when Local Controller becomes unreachable from Master.

Master Controller will have list of Local Controllers that are attached to it. And if one or many Local Controller goes down or becomes unreachable from Master, we could enable a trap on the Master to notify WLAN admin about the particular Local Controller status to be down.

"show switches" shows the list of Local Controllers attached to the Master.

(Aruba7205) #show  switches

All Switches
------------
IP Address    Name       Location          Type    Model      Version        Status  Configuration State  Config Sync Time (sec)  Config ID
----------    ----       --------          ----    -----      -------        ------  -------------------  ----------------------  ---------
10.63.0.20    Aruba7205  Building1.floor1  master  Aruba7205  6.4.3.6_52927  up      UPDATE SUCCESSFUL    0                       5
10.56.104.40  Aruba7030  Building1.floor1  local   Aruba7030  6.4.3.6_52927  up      UPDATE SUCCESSFUL    2                       5
10.56.104.41  Aruba7240  Building1.floor1  local   Aruba7240  6.4.3.6_52927  up      UPDATE SUCCESSFUL    2                       5
10.56.104.42  Aruba7010  Building1.floor1  local   Aruba7010  6.4.4.0_0000   up      UPDATE SUCCESSFUL    6                       5
10.56.104.43  Aruba7210  Building1.floor1  local   Aruba7210  6.4.4.0_0000   up      UPDATE SUCCESSFUL    6                       5

Total Switches:5

In the below scenario, one of the Local Controller's status is found to be down. Unless WLAN admin check the Controller's status by executing "show switches" periodically on Master Controller, he will not have any visibility on their reachability from Master. 

(Aruba7205) #show  switches

All Switches
------------
IP Address    Name       Location          Type    Model      Version        Status  Configuration State  Config Sync Time (sec)  Config ID
----------    ----       --------          ----    -----      -------        ------  -------------------  ----------------------  ---------
10.63.0.20    Aruba7205  Building1.floor1  master  Aruba7205  6.4.3.6_52927  up      UPDATE SUCCESSFUL    0                       5
10.56.104.40  Aruba7030  Building1.floor1  local   Aruba7030  6.4.3.6_52927  up      UPDATE SUCCESSFUL    2                       5
10.56.104.41  Aruba7240  Building1.floor1  local   Aruba7240  6.4.3.6_52927  up      UPDATE SUCCESSFUL    2                       5
10.56.104.42  Aruba7010  Building1.floor1  local   Aruba7010  6.4.4.0_0000   down    UPDATE REQUIRED      0                       0
10.56.104.43  Aruba7210  Building1.floor1  local   Aruba7210  6.4.4.0_0000   up      UPDATE SUCCESSFUL    6                       5

Total Switches:5

Rather having to check this manually, below trap could be enabled which will be sent as a SNMP trap to the trap receiver.

(Aruba7205) #show  snmp trap-list | include  Local
wlsxNConnectionBackfromLocal               Yes           Enabled
wlsxNConnectionResetWithLocal              Yes           Enabled

As shown below, traps can be seen forwarded to the trap receiver from the snmp trap-queue on the master.

(Aruba7205) #show  snmp trap-queue

2017-06-28 23:42:30 Master controller Aruba7205 IP address 10.63.0.20 lost connection with local controller Aruba7010 IP address 10.56.104.42 at Wed Jun 28 23:42:30 2017
2017-06-28 23:42:50 Master controller Aruba7205 IP address 10.63.0.20 lost connection with local controller Aruba7210 IP address 10.56.104.43 at Wed Jun 28 23:42:50 2017
2017-06-28 23:50:30 Master controller Aruba7205 IP address 10.63.0.20 lost connection with local controller Aruba7010 IP address 10.56.104.42 at Wed Jun 28 23:50:30 2017
2017-06-28 23:50:30 Master controller Aruba7205 IP address 10.63.0.20 lost connection with local controller Aruba7210 IP address 10.56.104.43 at Wed Jun 28 23:50:30 2017
2017-06-28 23:58:31 Master controller Aruba7205 IP address 10.63.0.20 lost connection with local controller Aruba7010 IP address 10.56.104.42 at Wed Jun 28 23:58:31 2017
2017-06-28 23:58:31 Master controller Aruba7205 IP address 10.63.0.20 lost connection with local controller Aruba7210 IP address 10.56.104.43 at Wed Jun 28 23:58:31 2017
2017-06-29 00:00:17 One or more licenses will expire in 23 days.