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New Member

LAN,SWITCH

DEAR SIR,

I AM INTO BROADBAND BUSINESS PROVIDING BROADBAND CONNECTION TO OFFICES/HOME , SIR I AM RUNNING A LAN WITH SWITCHES THROUGH WHICH I DISTRIBUTE MY CONNECTIONS, NOW THE PROBLEM IS THAT A CUSTOMER CAN ACCESS INTERNET WHEN HIS IP AND MAC ARE FOUND TO BE SAME BUT FROM LAST 20 DAYS WHAT IS HAPPENING IS THAT EVERY CUSTOMER IS GETTING SAME MAC AND SO THE WHOLE NETWORK IS JAM AND NO ONE IS ABLE TO USE INTERNET AS THEY ARE NOT ABLE TO GET CONNECTIVITY. PLEASE TELL ME THE SOLUTION

7 REPLIES
Silver

Re: LAN,SWITCH

Hello,

The MAC address is the layer to address of the hosts and it is hard coded to the NIC (some NIC's can be configured to use different MAC than the hardcoded). Normally switches do not change the layer2 address of the ethernet fram just forward them based on their forwarding table. Where is the MAC and IP linked together?

Krisztian

New Member

Re: LAN,SWITCH

Actually the company I deal in provides a username/password to a customer based on there IP address and Mac Address.

User gets connectivity from the server only when Ther server gets the assigned mac from the assigned IP Address

like for example

userid: pahujatravel

ip address:10.230.24.3

Mac address: 00:02:54:85:65:74

so like this every user has a diff ip address and a diff mac address but the problem which is coming is that the server is getting the same mac address from all the differnet ip addresses.

Silver

Re: LAN,SWITCH

Can you post the switch config?

New Member

Re: LAN,SWITCH

there is no configuration for the switch. simply a local lan is made with number of switches.

Silver

Re: LAN,SWITCH

Hi,

OK. It looks then you are not using dot1x authentication. Just for better understanding what kind of server are u using. Is it only for suplly IP addresses to the clients (DHCP) or what?

Krisztian

New Member

Re: LAN,SWITCH

yes it is only DHCP server

Silver

Re: LAN,SWITCH

I belive the router forwards the DHCP request to the server (by means of helper configured) and the server sits on different network. If this is the case the DHCP server should take into consideration that the DHCP discover came through a DHCP relay. If it does not recognize then will give the same IP as the router will send the Discover with its own MAC address facing the DHCP server.

This link fairly good describe how the DHCP relay working:

http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a00800f0804.shtml

HOpe it helps, rate if does,

Krisztian

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