ASA inter-vlan routing

Carlos Bergia — Tue, 12 Mar 2019 04:22:32 GMT

Hi, I have this situation:

A client of mine has a switched network. On that network where no vlan is configured, he has multiple IP address on the same vlan (vlan 1). So, I´ve installed a 5505 with two vlans, and asigned each vlan to ethernet interfaces. I´ve made 2 connections, from switch to each ASA interface. The problem is when I execute show arp on the ASA, I receive the same entry on both interfaces.

I hope in first place that you understand my english, and in second place you can help me 🙂

Best regards!

The ARP table will be built

Marvin Rhoads — Tue, 24 Jun 2014 20:44:07 GMT

The ARP table will be built based on the ASA seeing ARP broadcasts and replies. If the client has one VLAN (= one broadcast domain) then both interfaces will see all of that traffic and build identical ARP tables.

The correct way to change this would be to create a second VLAN for the second set of IP addresses and assign the appropriate interfaces (including the second ASA client-facing interface) to that VLAN.

topic The ARP table will be built in Network Security

ASA inter-vlan routing

The ARP table will be built