topic DHCP/MAC Reservations in Network Security

DHCP/MAC Reservations

swavconsulting — Tue, 12 Mar 2019 01:09:03 GMT

It you are using the ASA as a DHCP server, can you hold each specific ip address that the ASA gives out by the end components mac address?

DHCP/MAC Reservations

Jouni Forss — Mon, 04 Mar 2013 11:00:29 GMT

Hi,

I'm not sure if I understood you correctly.

Do you mean that can ASAs DHCP assing the host an IP address based on its MAC address? I mean always assign the same host (MAC) the same IP address?

To my understanding this isnt possible. Might be possible if the device hosting the DHCP service was a Cisco IOS device but to my knowledge the ASA has pretty limited settings when it comes to DHCP and it should only be used at the very basic setups

- Jouni

DHCP/MAC Reservations

jocamare — Mon, 04 Mar 2013 13:34:49 GMT

Just to backup what Jouni said.

DHCP reservation is not supported on the ASA, and doesn't look like it's going to be supported anytime soon.

An enhancement bug has been filed requesting this support:

CSCsw72963 ASA local address pools should support DHCP reservations/assignments

More info about the enhancemenr request, here:

http://tools.cisco.com/Support/BugToolKit/search/getBugDetails.do?method=fetchBugDetails&bugId=CSCsw72963

DHCP/MAC Reservations

swavconsulting — Mon, 04 Mar 2013 15:02:54 GMT

Thanks Jouni

That's was I was talking about. I didnt know this when i got the ASA, just wondering if you have any recommendations on what to use for a DHPC server and something that will allow mac reservations? Its a basic system with a ASA, C2960-48, C2960-24 switch and about 75 hosts on the inside interface. Any ideas would be helpful.

Thanks,

DHCP/MAC Reservations

Jouni Forss — Mon, 04 Mar 2013 18:24:55 GMT

Hi,

I guess there are even some options on the 2960 Switches

http://www.cisco.com/en/US/docs/switches/lan/catalyst2960/software/release/12.2_52_se/configuration/guide/swdhcp82.html

Though it doesnt list DHCP based on the MAC address but based on the port on the switch.

Switching and IOS devices in general isnt something I deal with on a daily basis so I am pretty rusty.

I guess the best option would be to have a server on the LAN acting as a DHCP server. Probably would give alot more options to work with instead of playing around with a network device.

But again, not something I work with myself.

- Jouni