Routing – Reduce ARP cache time-out

Answering the original router question: Arp caches are there to map an IP addess to a mac address. There's nothing unique about a router. .. it needs an ARP cache just like any other IP device.

Managed switches likewise need an Arp cache so they can communicate with the stations managing them.

As we discussed in chat, you need to add an IP address to your switch so you can communicate via ARP.

vlan 2
 name management_vlan
!
interface Vlan2
 ip address 192.0.2.20 255.255.255.0
 no shutdown
 no ip route-cache
!
ip default-gateway 192.0.2.254

This isn't what you asked about, but if you need to see what mac addresses have been learned on a Cisco switch, use show mac address-table.

Keep in mind that mac learning and ARP are completely different processes on a layer 2 switch. Mac learning is used for communication through the switch. ARP is required for communication to the switch itself.

I would run your APs in local mode and make sure you are trunking to the controller. Then put the ports that your APs are plugged into as access ports for vlan 10. This should get your roaming working.

In your controller, configure two interfaces with vlan ids for 20 and 30 (Controller > Interfaces). Then on your SSIDs assign the interfaces that your just created. (WLAN > [wlan_name] > Interface/Interface Group(G)).

When APs are in local mode, they tunnel all client traffic back to the controller to make a routing decision. This way you don't need to trunk to each AP and the roaming will be controlled by the controller.

I seen in your partial solution that you have to configure DHCP relay on the 2960S switch. I thought this was strange because the switch is a layer 2 device and DHCP broadcasts should work without it. That is unless the trunk isn't correct to the Mikrotik.

I have this setup in a few places where wireless is critical and it works very well.

Josh