Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
Announcements

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. And see here for current known issues.

New Member

Source MAC changes on routers

Hi all:

Is there any command that can be applied to routers in order to somehow keep original source MACs from LAN and not changing it when routing packets to a WAN?

Thanks

W.

5 REPLIES

Re: Source MAC changes on routers

No.

New Member

Re: Source MAC changes on routers

Hi!

Thanks for replying!

In order to let things clear, let me put an example (I know this could be quite stupid, but I have to report this to my boss :) )

On a LAN, a PC (A) sends a packet to another PC (B)on another LAN. Both LANs are connected thru a WAN link, with 2 routers). As packet goes thru Router A, this router will change PC A MAC address to its own MAC, and send it to Router B.

There is no command to avoid this and send PC A source MAC address unmodified thru WAN link to PC B, correct?

Thanks (specially for the patience)

W.

Re: Source MAC changes on routers

this is how switching works :) hence this is a no.

There is no command to achieve that or it will challenge the switching design basically.

What are you REALLY trying to achieve?

Hall of Fame Super Silver

Re: Source MAC changes on routers

Hello Walter,

the short answer is no.

I try to guess you would like to perform a packet capture.

unfortunately IOS embedded packet capture can do the opposite:

it can capture WAN frames and it can send out a LAN port to a PC running a protocol analyzer.

see

http://www.cisco.com/en/US/products/ps9913/products_ios_protocol_group_home.html

Hope to help

Giuseppe

New Member

Re: Source MAC changes on routers

Hi all:

Let me give you the context. We are using Cisco Contact Center with call recording and monitoring. It seems that it does not work when sending packets in different LANs thru a WAN link. The problem is that for recording, the system uses the source MAC address of the softphone (in this case, the PC) and that is changed in the routers.

I hope this clarifies situation.

Thanks to all for your help!

W.

154
Views
10
Helpful
5
Replies
CreatePlease to create content