topic ASA5508-X in Network Security

ASA5508-X

Docklands — Fri, 21 Feb 2020 15:08:09 GMT

We have two ASA5508-X firewalls configured for HA main/standby running 9.7

If we connect a Windows (V7 or 10) PC either directly or via a layer 2 switch to the outside ports of the ASA, the static IP address configured on the PC is overwritten with a 169.254.x.x address. DHCP has been disabled on the ASA. If the PC is connected to a switch it retains its static IP address.

Has anyone experienced this before? Is this a Windows issue or the ASA?

Thanks

Mike

Re: ASA5508-X

Karsten Iwen — Sat, 13 Jan 2018 12:34:19 GMT

I would say that this is a windows problem (with DAD), but you can mitigate it on the ASA by disabling proxy-arp:

sysopt noproxyarp outside

Re: ASA5508-X

Docklands — Sat, 13 Jan 2018 12:44:38 GMT

Thanks Karsten. I’ll give it a try on Monday and let you know