VPN client mac-address issue

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Oct 13th, 2008
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i have configured easy vpn server on ASA5550 and my remote VPN clients connects it successfully. My problem is that i have an application which needs MAC address in order for successful communication. i have found that mac-address is the same for all vpn clients, how can i get different mac-address against different vpnclients.


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satish_zanjurne Mon, 10/13/2008 - 02:20
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When a packet traverses a L3 boundary, it's source MAC address will definitely change.

Are sure your Application cannot run on IP Address , but only MAC address ??

HTH...rate if helpful...

itdsmartnet Mon, 10/13/2008 - 02:41
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Thanks for your reply, by issuing ipconfig /all on the systems where vpn client is installed, i have found that all the systems with vpn client installed have the same mac-address. i have installed vpn clients on Windows XP machines. My server needs ip address with unique mac-address for its communication with the clients. My VPN clients are getting unique ip address but not the mac-address. The mac-address listed on ipconfig /all is 00-05-9A-3C-78-00.


itdsmartnet Mon, 10/13/2008 - 03:06
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please help me. i want my vpn clients to have different ip and different mac address.

satish_zanjurne Mon, 10/13/2008 - 03:42
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Can you paste your output of "ipconfig /all"

and "arp -a" ??

satish_zanjurne Mon, 10/13/2008 - 03:50
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1.Are these all VPN clients are at same location geographically?

2.If they are at same location are they connecting to head end through some NAT device ???

satish_zanjurne Mon, 10/13/2008 - 04:03
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This is looks like a common issue !!!

Not able to find proper doc on this..

milan.kulik Mon, 10/13/2008 - 23:17
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my VPN client is using the same MAC.

No notice in any documentation.

I found that value on my PC while searching Windows registers but didn't try to change it.

Basic question:

How does your application check the client MAC address while connected via an L3 device (i.e. in another subnet)?



itdsmartnet Tue, 10/14/2008 - 00:25
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my vpn clients join domain remotely and my server which require mac address and ip is on my domain. so it checks the mac address with the ip address to get the client access.

satish_zanjurne Tue, 10/14/2008 - 03:23
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So what ??

Is all hosts across globe who are connecting to their enterprise network using Cisco VPN client have same MAC address ??

Cristian Silva Tue, 08/17/2010 - 06:44
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I have the same problem, my ip communicator gets their "name" by the mac-address of the interface , I want to connect more than one ip communicator but they tries to register to my callmanager with the same "name" that is based on the mac anyone knows how to change it.


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