Change mac address cisco asa 5505

I got an ASA firewall at a great price to use as a router at home and also to get some hands on with Cisco gear. Since I'm using the default configuration, In the it wasn't exactly how I I have a a basic question though about. I'm on my phone so this will be short.

Configuring Switch Ports and VLAN Interfaces for the Cisco ASA 5505 Adaptive Security Appliance

Yup, because of the built in switch design of the , the physical ports don't support any direct configuration other than basics like speed and duplex and vlan. All layer 2 and 3 networking config and up from there are done in the software, or 'logical', VLAN interfaces. And I want to keep my IP address from changing.

But my IP did change anyway. Here is the config I used: I guess I assumed MAC addresses would have to be globally unique to be of any value as an identifier. I suppose the ISP wouldn't ever know the difference. Where xx. For the standby MAC address, the address is identical except that the internal counter is increased by 1. For an example of how the prefix is used, if you set a prefix of 77, then the ASA converts 77 into the hexadecimal value D yyxx. I'd love to read up a little myself, mostly because I need to set up 7 more branch offices in this exact same way, so it'd save me a lot of headache to be able to predict one way or another what MAC my ASAs will be broadcasting to the ISPs.

I could be a little wrong about auto generation part. Seems to be for Context Interfaces, but give the idea how Cisco simulate uniqueness. Most of info is from Cisco site - http: Frol and I were kind of on the right track, but not quite. I don't really care what the MAC is going to be, I just need to be able to view it reliably somehow. You are looking for 'outside' one. OK, thanks to Prapanch for clearing up what was happening with those MAC addresses and why, and thanks to Frol for providing the practical advice on what to do about it.

I needed both posts to solve my business problem.

Changing MAC address on Cisco ASA 5505 firewall...succeeded but have a question

I've since run a 'show interface' on a handful of other Cisco devices around the enterprise and they all seem to behave this way, just like Prapanch said. I thought MAC addresses were reserved for use by hardware interfaces. In my mind, this gives that interface 2 MAC addresses and that just doesn't make sense to me. Don't get me wrong, I'm assuming there's a good reason, I just don't know what it could possibly be. To continue this discussion, please ask a new question.

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13 Replies

Interface Vlan2 "outside" So I guess it is this one? Thanks Yea, I don't need to set it in the firewall.

How to Install the Cisco ASA ASDM Launcher: Cisco ASA Training 101

Thanks for your help! Hopefully its the right one haha.

[SOLVED] invisible or inaccurate MAC address on Cisco ASA ? - Spiceworks

Latest Contents. Created by Edgar c Francis on Distribution listsA distribution-list is used to control routing update either coming to your router or leaving from the router. It is used for implementing policy that causes the packet to take a different direction. Policy based routing allows source based routing.


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Routing table is destin If you are not sure about what is BGP communities are and how its work then I ad Communities can be used to mark a set of prefixes that share a common property. Any BGP router can tag routes in incoming and out In this section we will see the configuration of two RR servers and will learn about deep RR behavior