1

I am new to Linux. Today, I installed Linux Mint (17.2) and tried to connect to the internet via a broadband connection. My Internet Service Provider (ISP) provided me with a fixed MAC address that they expect me to use as computer hardware identification. Thus, I need to change my current default MAC address. After doing some research, I've found out that there is a macchanger package that I could use. However, this requires a working internet connection to download, so I couldn't do that. Alternatively, I've tried the installed Network Connections application to edit the MAC address of my network adapter, but after changing it, it got set back to default. I've also tried the following command: sudo ifconfig hw enter <MAC Address> but the MAC address remains default.

So, what other options do I have to resolve my problem?

  • Before we can help you, can you tell us why you need to update your MAC Address by editing your post? – eyoung100 Jul 3 '15 at 19:18
  • Sorry , can't understand what do u mean mean ? – shuvroMithun Jul 3 '15 at 20:06
  • Your ISP gives you an IP Address. Your computer has a MAC Address that's hardware dependent, so why do you need to change the address of hardware. – eyoung100 Jul 3 '15 at 20:10
  • No , my ISP give me a MAC address not an IP adress which is 00:E0:4C:1A:6B:3F – shuvroMithun Jul 3 '15 at 20:12
  • According to Coffers MAC Address Finder, that address belongs to a device built by Realtek Semiconductor Corporation. Is that the device in your Linux Mint Computer? – eyoung100 Jul 3 '15 at 20:17
2

Problem

You bought a new computer to replace your old one. You brought it home and followed the quickstart guide, and it's all setup. You then disconnected your ISP's equipment, or at least turned off the power to disconnect your connection. You then plugged everything in exactly the way it was before, and turned on your new shiny PC/Laptop etc. only to find you cant connect to the Internet.

Reasoning

Some ISP's, including the OP's limit their network connections by monitoring your computer's MAC Address in what's called a Bridge Table. The Bridge Table stores the MAC Address of every user connected to the ISP. When your ISP connected you, i.e., you started paying for service, you were given a bridged/bridging modem, to allow for transparent bridging. See Figure 1 (modem type and brand are irrelevant, I just needed a picture):

Modem Setups

In Transparent Bridging your ISP can only see the MAC Address of the First Device connected past the modem. The modem's only job is to make sure you are connected properly and achieve Sync. In Figure 1's case the first device is the Desktop PC, therefore that Desktop PC's Ethernet Card MAC Address has been stored by your ISP. If you swap out PC's the MAC Address from your Old PC (stored in the Bridging Table) no longer matches the MAC Address of your new PC.

Note this also happens when you add a router, as in Figure 2. The MAC Address of the router no longer matches the MAC Address of the PC stored in the Bridging Table. In both cases, since the addresses don't match, the transparent bridge is broken, which is why the OP and others can't connect.


Fixes

Now that we understand why the bridge broke, we have 2 major ways to fix the problem.

  1. MAC Address Cloning - This is what the OP is trying to accomplish. The first PC or device that was connected to his service contained a network card with the MAC ID of 00:E0:4C:1A:6B:3F. Using Coffer's MAC Vendor Lookup, we can determine at least who made the original Network Card, in this case, Realtek. Assuming we no longer have access to the device, we must Clone its address as seen below for Windows:

MAC Cloning in Win 7

and here for NetworkManager Based Linuxes:

MAC Cloming in NetworkManager


Taken from: How (and Why) to Change Your MAC Address on Windows, Linux, and Mac


Personally, I hate Fix Number 1, but it's the most common. It's common because some ISP support people are taught that it's normal, and the others are just lazy. As such, I consider the fix below the "more proper" fix."

  1. Call your ISP support line, and kindly wait for a representative. Tell him or her that you bought a new PC/Laptop etc, and that you only need the Bridging Table cleared, because you know that the old MAC Address there won't match. Don't lose your temper because the representative will either respond:

    • that he can do that. When he asks if he can do anything else, say No, and offer to rate his call, as he responded correctly.

    • with no response. This is bad because he will try to lead you to Fix Number 1, after following the steps lined out in the helpdesk documents. If he does this ask for his supervisor, or another representative until you get one that responds favorably.

2

I think you just missed the ifconfig command a bit. It shouldn't be enter it should be ether as in ethernet. Also you are missing the interface. Try something like:

sudo ifconfig eth0 hw ether 00:E0:4C:1A:6B:3F

Change the eth0 to match whatever interface name you are trying to change.

-1

MAC addresses are hard coded into each nic (network interface card) and cannot be changed. You can spoof the mac address but that is not what you need.

Perhaps your ISP is using ipv6, if thats the case you might think its a mac address because it looks similar. Ipv6 example; FE80:0000:0000:0000:0202:B3FF:FE1E:8329

It might be that your ISP may need your mac address of your devices but I'm thinking that is not the case but rather the ipv6 ip address.

In the case you need to configure the computer for ipv6 I'd suggest closing this thread and ask that question pertaining to configuring your computer for ipv6 on linux mint.

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