Putting Comcast on Notice

April 5, 2008 • 34 comments

safari page not found screenshot
Creative Commons Licensephoto credit: stephen.hackett
For the last few days around 10:00pm till sometime during the next day my internet connection is down. At first I thought it might be a fluke and reset the modem and it still wouldn’t work, well this Friday it wouldn’t come back on at all. I decided to get of the computer and give Comcast an ear full.

I call them up and am prompted with the worst automated system second only to Bank of America. After finally getting a human turns out it’s a sales rep who cant help me with anything technical nor can he transfer me to the tech dept. How utterly useless. I call back a few minutes later and get a tech rep on the line, and immediately ask for an appointment for someone to come out and check the line, (since I have already done the standard reset procedures as well as release/renew on my IP). Of course they don’t have an appointment on the weekend, so I ask for the earliest one on Monday.

I call back this Saturday and to confirm, and they tell me that my appt is on Tuesday. Um… what the heck? So I decide to give them a chance and troubleshoot over the phone, after 30 minutes of getting nowhere, they rep on the phone found out that a slot was available today at 2. Perfect! The tech will come and fix the issue! Too bad this isn’t a perfect world.

The tech shows up on time, which was great however he turned out to be the most condescending and unhelpful person I’ve ever met. When I would ask him any sort of questions, he would reply in a sarcastic and mocking manner. He fiddled around a bit as if he didn’t care or they weren’t paying him to be here.

Finally got up and went out and brought his “test” modem in. it looked like a new model, and he plugs it in and some of the lights start blinking and gets this “WooHooo! I’m a genius” look on his face, soon to be replaced by this “crap… I look like an idiot” face.

Obviously his test modem did very little. He decides it must be the line in the backyard, he’s gone for about 10 minutes, come back and says he fixed the filter out back, so I’m thinking… uh ok sure maybe that was it. At this point the unhelpful tech hooks up my original modem to my Mac and I have an IP address, hooray! So he was good for something. I’m online. Awesome. Well what about my other PCs and my router, well turns out he cant help me with that. I plug the modem into my PC and I get an IP but I still cannot get online. I ask him about this and says well maybe its your PC or your wire. My wire? O RLY? Ok we’ll use the wire that was working for the Mac on the PC. Oh guess what… still not working.

If it’s not the wire than what is it? His response is simply… you saw it working on you’re laptop… I’m done. And in 5 seconds he is downstairs and out the door. As he is leaving he says try restarting your computer… I wanted to hurl the Comcast modem at him.

I call up Comcast again to let them hear my thoughts about the condescending tech with the 7th grade education… well they cant help me on Saturdays… are you serious? Ok fine… then at least troubleshoot my modem, 30 minutes later… they still can’t figure out what it is, and am forced to I schedule another appointment.

Something crazy was going on. For those of you that know me, I’m pretty tech savvy and know what the heck I’m talking about. However I couldn’t put my finger on it. Why would it only work on the Mac. (And don’t give me that, Mac > PC) crap because after resetting the modem, the Mac wouldn’t get online either. So I start fiddling around and I push the “reset” switch on the back of the modem and connect it straight to my brothers PC laptop. Instantly he is online. What the heck? Ok… well know let me plug it back in to the router, and see if the rest of the computers can connect. Crap. Still not working. Ok now I’m slightly confused. Each time I reset the router and plug it in… only the first machine works, and usually its my Mac that works because it’s the one I’m testing wired/wireless on.

Well after messing around and trying different things, we (my brother and I) determine that the ridiculous Comcast modem (model: DPC2100R2) is caching the MAC address of the first machine you plug in. This happened to be my MacBook Pro.


Well this problem was only solvable by cloning the MAC address of my MBP to my router. Making the modem think that it is still talking to my MBP.

Once we cloned the MAC address the router got an IP and we were on our way.

<sarcasm>Thank you Comcast for educating your techs on how to solve this issue with your craptacular equipment. </sarcasm>



34 Responses to “Putting Comcast on Notice”

  1. April 6th, 2008 9:01 am Skarsol

    Heh, for the record they’ve been doing this for at least 4 years (well, Time Warner was, so now Comcast), so that makes it even worse that the tech had no clue what was going on. :P

  2. April 7th, 2008 9:00 am ComcastCares1

    On behalf of Comcast, I would like to sincerely apologize for the inconvenience.

    I would like to learn more about your experience so that we may prevent any recurrence in the future. If it is not so much of a trouble, will you please contact me so that I could get your information?

    Thank you in advance!


    Mark C.
    Comcast Executive Offices

  3. April 7th, 2008 3:13 pm Weili

    The sad thing is, we don’t have much of a choice when it comes to getting broadband. It’s either cable or DSL and the services they provide are in general horrendous. To be fair, they do one thing very well, taking money out of my bank account every month.

  4. May 13th, 2008 2:22 pm DJames

    I wish I had your simple resolution….I am on tech number 5. They state that they have a policy that after 3 techs in 30 days the issue will need to be bumped to a super tech or supervisor. Unfortunately the supervisors do not want to face me. Let’s just say that we have on average 125 modem resets over a 4 day period. They tell me that this is not normal…but do not know how to fix it.

    Oh….and get this…they charged us on two of those visits they charged us a $19.95 service fee each. It took an act of Congress to get those reversed.

    I share in your frustrations.

  5. August 21st, 2008 10:11 pm MellyBelly

    I’m stuck with craptacular comcast and to make it worse, a father who still uses early 90′s computer security tricks and knowledge. I’ve found the only way to deal with the issue is to get a wireless router that allows for a LAN connection to any necessary computers.

  6. December 24th, 2008 10:41 am Dag Magnuson

    I have the same issue, comcast has a static entry in their dhcp server for the mac (media access control) address of my laptop and they refuse to acknowledge it. The only way I can get my lan connected is by cloning the MAC address of my laptop onto the router, which breaks other software I run on my lan (2 identical MAC addresses on same ethernet). These Communistcast idiots that answer the phone know nothing about networking so they’re 100% useless.

  7. July 3rd, 2009 9:45 am omg you are the biggest retard

    What the fuck comcast have to do with YOUR equipment! It’s like demanding from BMW that they fit in there your grandma’s rocking chair because that’s what you want it.
    They’re only responsible for good signal to your modem and the rest is up to you!
    Yes, I used to be tech for a subcontractor for comcast and assholes like you made my life impossible, because fucknuts like you, would expect that I’m supposed to sit there and resolve every issue that there is with their computer including virus removal!!!
    Even before I was a tech I knew you have to fucking restart cable modem every time you switch your computer
    What a retard assfuck you are! Learn something about computers yourself before you start blaming others!

  8. July 3rd, 2009 10:12 am Zaki

    First of all the modem doesn’t belong to me, it belongs to Comcast. The fact that they have it set to save the MAC address of the first device you plug in and you can’t clear it until you do a RESET (not a restart) that isn’t my fault. If you read the entire posting you’ll see that I “restarted” their modem plenty of times to get a proper signal. What angered me more is the lack of service from their tech that came to my house to fix the issue with their modem. I’m sorry you hated your job at Comcast. Dealing with the tech that came to my house and after reading your response I’m pretty sure Comcast does hire people with only a 7th grade education… But hey job security right? A modem should never save the MAC address of your device. It will result in complications when you plug-in a different device. As a tech you should know/understand that.

    But hey… Thanks for the input.

  9. July 3rd, 2009 10:40 am omg you are the biggest retard

    The more I think about your retardation, the more it boils my blood. You’re the type of shit nugget that will call 911 because you didn’t get your pickles on your hamburger, aren’t you?
    Let me ask you something. How many different models of routers is there? A 100? 200? 1000? 2000? So now you expect that that tech supposed to know configuration of every router of every model!? You fucking shithead, it didn’t occur to you that your model is not the only model in use, did it? What if you purchased brand new top of the line router that just came out previous day? Would you expect the tech to be aware of it and configure it?
    Wrong! You motherfucker! This is what I would do, I’d come to your house unplug your shitty router plug in the modem directly to any of your computers, restart the modem, and if I’d get internet, just like that other tech I’d walk out of your piece of smelly shit person. Next time READ THE FUCKING ROUTER MANUAL! or call fucking tech support of the router they will tell you to CLONE THE FUCKING MAC ADDRESS.
    Fucking asshole. Fuck you and every person that agrees with you!

  10. July 3rd, 2009 11:07 am Zaki Mirza

    Wow you’re getting pretty angry over something that has nothing to do with you. Who said anything about a router? The modem model is mentioned in the posting. Aldo I called and spoke to several techs and none of them could determine the problem. And the field tech had no clue either.
    Yes I expect Comcast to train their techs with various equipment not just their own.

    Personally I don’t like pickels. Seriously. Thanks for the input.

  11. July 29th, 2009 5:18 pm Zelf

    Your post just fixed my problem. Sure enough connecting to the Comcast modem directly from the computer so it picks up an ip. Then cloning the MAC on the computer that connected to your Router, then connecting the router to the Comcast modem and refresh the DHCP works. Just got off the phone with a tech who told me he was in “advanced” tech support at Comcast and that he thought to fix the problem that I should clone the DHCP IP Address Lease. UH……….. Yeah. And I hung up at that point. Customer Service is dead, and Tech Support no longer has technical skills.

    Also, a couple posts up. Pretty shameful talk. You are an embarrassment. A sure sign of intelligence is the number of F bombs you have to drop to try to prove a point. Clean it up.

  12. July 30th, 2009 9:24 am Zaki

    Thanks Zelf. Glad it worked out for you.

  13. August 20th, 2009 2:55 pm KC

    Thanks a bunch for posting this. I believe this may have solved my problem too. I wont’ know until I can try it once I get home, but at least it explains to me why nothing was working on any computer except the one that the install tech had set their equipment up for.

    Unfortunately, I know I did try to reset the modem, but I’ll try once again, in case I had accidentally done it while the computer wasn’t connected.

  14. September 1st, 2009 7:07 am SE7EN

    In response to “omg you are the biggest retard” and “Comcast Rep” who posted earlier in this post :)

    The biggest issue with your tech people is that they know absolutely nothing about “tech”. You sub-contract out these low-life people who can’t even pass their Cisco tests. I admit, there may be some comcast techs who are actually worth a damn, but I haven’t met one in Chicago.

    The experiences I have had required me to switch all my services to AT&T because I was so disgusted with service. The sub-contracted company has asked for gas money after being 2 hours late, I’ve had numerous issues with packet loss even after checking my own lines and the tech “checked the lines”. The more people hate comcast the worse they do, you’d seem to think it would be the other way around.

    Don’t give me your words of disrespect either, it is rather funny how the “comast tech” above posted all of the profanity, it just shows his true IQ level.

    In conclusion, I can actually label myself a tech due to the certifications I’ve received from Cisco.

  15. October 6th, 2009 6:22 pm b

    I have to say that the technician from comcast is a retard. Im a technician in Arizona for Cox, sub also, and we do not treat our customers like that down here. You do tend to get the asshole customers, but as a tech you learn to deal with it. Also with that he should have never left without it working properly. It does not matter what modem or router you have they all work the same. Im sorry you all have to put up with techs like this guy.

  16. October 18th, 2009 4:39 pm Justin

    I’ve had the same issue a few months back, except it wasn’t just my internet but everything on the line in general. I had four different technicians come out to fix the issue. After the fourth person the issue was still not resolved and they sent out a “Supervisor Technicians” as what the phone rep clearly stated. Well being that I manage three apartment buildings I found that they did not send out a “super technician” it was just a normal Comcast technician that just played with the line and saw that the last four technicians either never checked the box or never hooked up my service in the box located in the basement. And they kept asking me why I wanted to cancel my service… Go figure!

  17. October 23rd, 2009 9:50 am albert

    I have to jumpstart my router. Cloning the computers nic to the router alone doesn’t get me online. If I hook the computer to the modem, get a comcast ip# unplug the computers e-cable from the modem then hook the cloned router to the modem and the computer back to the router. The router will then perform at least until lease renewal or power loss. At which time I have to jumpstart again. PITA . Comcast says router isn’t supported, but they also said that about my modem ( not a comcast modem). Still working on finding the correct and complete solution that doesn’t involve cable swaps.

  18. January 11th, 2010 2:10 pm adamic

    Well I am sorry you had these problems. The solution is to plug the router into the cable modem and reset the cable modem. This way the cable modem uses the mac address of the router. Then the router (using DHCP) will give out the local addresses for all your other computers. If that doesn’t work then something is wrong in the router settings. Reset the router (they all default to working settings) You will, of course, lose all those tables for your firewall. ***NEVER PLUG A COMPUTER DIRECTLY INTO A CABLE MODEM*** It takes seconds to get hacked.

  19. January 31st, 2010 7:24 pm coldinnh

    My Comcast service came with directions to plug cable from modem into my mac. Where do I get info on what to do to avoid directly plugging computer into cable modem? I would love to plug my pc laptop into Comcast line, but fear it will take days (and blood pressure points) to get it working again. I understand Comcast only wants you to use 1 computer per cable modem….
    And I am trying to learn about computers, but until I get there, I have to rely on the help of people who know more than I do.

  20. April 14th, 2010 5:33 pm ECW

    *chuckle* This is the normal behavior of most cable modems, (and techs for that matter) there are reasons on their end for why it takes awhile to register a different MAC address.. It would have eventually, ‘spoofing’ is not required, but it is faster sometimes. I cannot agree that the tech was necessarily dumb.. It may be nice to think so, but I imagine he just didn’t give a shit. It really is Nnot the job, or concern of Comcast to get more than a single, directly connected machine on-line..

    He may have even known that it takes awhile for it to register a new device when switching around the way you were, but was enjoying making another ‘stupid user’ (as they see them) figure it out for him/her self. It is how he amuses himself maybe.

  21. April 14th, 2010 11:55 pm adamic

    I would just go buy a router which will give you multiple local addresses and a hardware firewall.

  22. July 25th, 2010 2:05 am Brady Mills

    Ha! I loved the responses from the Comcast *subcontractor* — and the response from *We Care* @ Comcast. They should be ashamed that they hire (or subcontract) people who feel it’s appropriate to publicly admit their affiliation with their company while having fits of rage on someone’s message board.

    I am glad you resolved your problem though. I’ve been struggling with Comcast for a very long time. At one point, my business services didn’t work at all in my (new) office building, and when they did it was very rare. So, my employees ended up spending most days at the coffee shop, where the Internet was more reliable. Probably wonderful for my employees but very embarrassing for me — It was a brand new office and rendered useless because Comcast.

    Unfortunately, commercial services require a three year contract (which I had to have, because it was a commercial building)…. and even though their service didn’t work they had me locked in. After complaining enough and filing a complaint with the FCC, they canceled my contract and apologized. I thought it was all over…. at last.

    Six months passed and all was well. I had switched back to using residential services which worked better than commercial for 1/3 the price and with much faster customer service response. Everything seemed to be perfect, until I received a call from a bill collector demanding that I pay Comcast $3,000.00 for early termination of my contract. What?

    I immediately called the Comcast representatives who canceled my contract (I had their names and several email correspondences) thinking it was just some paperwork error. They denied ever talking to me.

    So I decided to continue calling them and record our phone conversations where they vehemently denied ever speaking with me. I then approached them with the recordings and emails and threatened to contact the FCC again.

    Although they didn’t cancel my contract, and I’m still on Comcast’s subpar business class internet, they did reduce my rate to residential prices and are now only requiring me complete one more year of misery. I probably should have just taken them to court, but it isn’t worth it. I’d never win against the multi-billion dollar ivory tower of digital greed…

    So while I ride out my Comcast sentence, it’s nice to read that I’m not alone. Perhaps I should start a support group when I’ve been released. “Hello my name is Brady, and I’m a Comcast Survivor…”

    “… because I will survive, Comcast! I will.”

  23. November 5th, 2010 5:33 pm making sure you know

    if the router is yours the tech cannot touch it, and if you knew it was a problem with the router, Netgear or linksys have a technical support for all of that. all you had to do is call them up and tell them your model and they will guide you thru the process, next time make sure whose fault it is before writing a long and unnecessary speech about Comcast you obtuse customer.

  24. November 6th, 2010 10:18 am Zaki

    You obviously didn’t ready my long and necessary speech about Comcast. The problem wasn’t the router. The problem was the modem stores that mac address and it doesn’t reset easily. But hey, thanks for dropping by!

  25. December 7th, 2010 1:40 am FunnyThingIs

    Haha came across this post, I had the exact problem.

    I had called tech support, and told the person “hey I lost the mac address after I reset my router to defaults to fix some unrelated issue (I had replaced the router that had the original mac a year ago), can you guys reset it?”.

    Note: I’ve been managing datacenters/ops teams for 12yrs, networking is kind of second nature to me.

    What do they tell me? “No it doesn’t work that way, we don’t cache your mac address” and “from my end I can see your router and it looks fine, this is clearly a problem with the router, let me forward you to Dlink’s tech support”.


    Ok admittedly my cable modem isn’t something I pay much attention to day in and day out, so honestly I don’t know if resetting it would blow away any important settings (like, voip, for example). Old ops/IT wisdom kicks in, don’t fix something that isn’t broke, so I left it alone.

    Luckily I found my old router in the garage, still working, and got the old mac address…Entered it on the wan interface of the current router, and its all good. I then broke out the ptouch and labeled the current router with the old mac address just in case this happens again…

  26. March 15th, 2011 5:10 pm realbadone

    well it looks like it wasn’t comcast’s problem to began with. their internet was working and they should not have to troubleshoot your modem witch you did not buy from them. if i were your internet company and you asked me troubleshoot your computer or router i wouldn’t and at same time if i were the one calling isp i wouldn’t expect them to troubleshoot either i should call my router manufacture. thats my 2 cents

  27. March 29th, 2011 9:28 am RevFelix13

    all cable companies iive seen records macs. my cable company still has the mac registered from a pc i trashed years ago. i cloned its mac to a router and every thing ive ever connected works. its that simple. i only see a problem if your using multiple computers with one cable modem and no router. your the problem there. no matter how dumb tech support may seem, get a grasp on the issue before you get mad and blame someone else. also get your cheap ass a router and all these problems will diassapear

  28. March 11th, 2012 8:54 pm Comcast Technician

    Hi There, The name’s Jake, I can see that this post was created a while ago but I figured, hey, why not put my two cents in.

    First off, I’m sorry that the tech was rude, makes us technicians look bad. From what I’ve read I see that you where upset at the fact that the modem was not releasing the Mac address associated to it very easily.
    There’s a couple reasons for this One being that if your not hooking up to a router then we would assume that your only hooking up one pc and that’s why the modem grabs that first Mac address.
    Now when I’m installing modems or fixing someones issue here my normal rule of thumb for getting a router to work with the modem.
    1. Hook straight from the modem to pc and get the internet up.
    2. Unplug that line and then go to CMD and run as administrator. Then type the command ipconfig /release. This releases the ip assigned to that pc.
    3. Unplug the modem from the back and keep it off for 30 sec. This releases that mac address.
    4. While everything is still off(modem and router)
    Hook a line up from the modem to the router.
    5. Plug the modem in and wait 5 secs to power on the router. This is called a power cycle and in a normal situation this will allow the modem to grab the Mac address of the router and allow the router to assign ips to multiple pcs.
    5. Plug in from the laptop/desktop to the router.
    6. While still in CMD type ipconfig /renew. This renew’s the ip on the pc we used before and allows it to get one from the router.
    7. Get into the router setting and set up wifi. Procedure varies from router to router.
    8. Connect to wireless and test the internet. 9 times out of 10 this will solve the issue.

    I hoped this info helped the situation of the Tech to Costumer relationship. And again I apologize on the way you have been treated by the tech, Both in this thread and at your home.

    Oh and if this helps I’ve only been a Comcast Technician for two months now, And from I can see I already out match some of the so called veterans of cable out there. So fellow techs, If there’s something to learn here it’s this. Always treat the costumer with respect, It’s never your place to disrespect the people that pay your bills. And if you don’t like that then get this, There’s always another job for you elsewhere.

  29. September 15th, 2012 11:10 am Finally_Found_IT

    I just wanted to jump on and say that the post from the above Comcast Technician is exactly what I needed.

    I experienced a power surge a few weeks ago that took out all of my computer equipment. (And before anyone says anything, of course, everything that was blown out was connected to a “surge protector.” As you can tell, they worked as advertised. I guess the only way to truly insulate your electronics is a surge protector on the electrical box of your house. Although it is pricey, it really sucks replacing all of your electronics, fuses, or the power supplies inside your electronics.) So I replaced the power supply in my computer, replaced the power supply for my laptop, threw out my router, and called Comcast to replace the modem and cable box that were no longer working.

    Once I had the replacement modem, I could not get it to connect to a router. They would ask me to unplug the modem and recycle the power. After it was fully operational, then hook up the cat 5 cable directly to my computer. Once they had ensured that I had a functioning internet connection they were done. They would assist me no further than that. What they would do is refer me to another technician, and to use their services, $79.99 one time charge and $19.99 monthly to provide me with assistance on this.

    So naturally, I refused to use this. All that I required was someone telling me that I was now required to clone the MAC address of my computer on my router in order to establish an internet connection for all of my needs.

    To anyone with issues similar to this, follow the steps in the previous post. Which I have summarize below:
    - Connect a computer to your router
    - Clone the mac address of the computer onto the router
    - Cycle the power on the modem
    - Connect the same computer, whose mac address you cloned to your router, to the modem
    - Allow the computer to have a IP address assigned to it and ensure that your internet connection is functioning
    - Disconnect your computer from the modem
    - Connect your router to the modem and suddenly now you can have a functioning internet connection for all of your internet needs

    I never needed to do this previously. I attributed all of my problems to Comcast and the results of the power surge. Turns out, Comcast just decided this was a good way to sucker people into paying for a pricey solution. All they had to do was allow their techs to say, “Sorry, I can’t help you any further. You might want to attempt to clone your mac address to your router and see if that helps you.” Instead, they treat you like you are a moron and incapable of knowing how to use a computer and all of your electronics, and if you are desperate enough, pay them a lot of money to give you a simple solution.

    Every one of them would reply to my inquiries by talking about my wireless router. I began to get infuriated by this. I never used those words, they just kept assuming that I was incapable of setting up a wireless connection to the internet. And for the low fee of 100 dollars they would help me in my stupidity.

    To the salty technician of previous posts, wow. You fail to recognize that some people are pretty resourceful. We will find a way to circumvent paying people like you to fix it for us. Especially when you treat people who don’t do this 10 times a day like they are somehow inferior to you. That is exactly what this thread has done.

    Probably done in an attempt to provide absolute attribution for crimes committed on the internet, Comcast started using this simple step to ensure they know exactly who is connected through a customer’s internet connection. I’m sure it’s easy to maneuver around for someone trying to use the internet connection of a person who unwittingly provides them with the opportunity. The use of security measures on wireless connections is widely advocated and easily sidestepped by anyone intent on getting on your network, I just wish that people would allow us to know that they are using this method of protecting the hardwired connection as well without charging us big money for that knowledge. Comcast should publicly encourage customers to use as much security on their networks as possible and make it freely available knowledge for those who seek it, it protects your customers from criminals getting on individual networks, using someone else’s service, and the ISP from blaming their unsuspecting customers for the actions of others. Oh, and it might even provide Comcast with more customers by forcing people to pay for their own service if they can’t find someone connection to steal.

  30. March 22nd, 2013 2:19 am MCoate

    I know this post is EXTREMELY old, but I couldn’t resist piping in due to the utter ridiculousness of the problem identification… and to also clear this up for anyone who comes across this thread in the future.

    This “issue” is very simple(I do believe their tech should have been able to diagnose and explain this in just a couple minutes however.. you know, being a “technician” and all) and IS NOT an issue whatsoever, but very much the proper function of the device.

    That Comcast Cable Modem(essentially a router) has one port for you to plug into. As soon as it sees a device plugged in, it immediately(and “permanently”) stores this device’s MAC address into the MAC Table of the CM so it knows where to forward packets on to.

    One and only one MAC address can be stored per port(normally), this is how Layer 2 works, think of the CM as a one-port switch. So once it learns a MAC address, it keeps it in memory until manually cleared(unplugged for a minute, possibly the reset button). As you can see, plugging a different device in would prevent packets from ever be forwarded on correctly as it’s MAC addresses is nowhere in the CM’s table(the original device’s is).

    “That’s bullshit! I used to have a router plugged in and had multiple machines connected!”

    Absolutely possible. How? In similar fashion to the Cable Modem(with MAC and/or ARP tables). A home router(which probably has a built in switch or WiFi) creates its very own MAC Table of all the machines connected to IT so it knows how to get packets back to each of the different machines. So for every port that has a device connected, there is an entry with the device’s MAC Address(like the Cable Modem).

    *Side Note: This is the fundamental advantage of a switch over a hub. A hub carries no Layer 2 information (MAC table) and floods ALL packets to every port, making it terribly inefficient.

    The Comcast CM has a “sticky” MAC Address function so that once it stores a MAC, it keeps it “forever”(of it’s running memory). So by unplugging the CM for 30 seconds or so it clears the memory, and thus the MAC entry out of the table, and awaits a first device to be plugged in to build its table. Just make sure you only plug the final device you want in there(a router in this case) otherwise you will need to reset it again to clear the table so the proper MAC is “stuck”.

    Standard networking, hope this helps anyone/someone.

  31. June 16th, 2013 8:36 am jon

    This Jerk need attrention from Mommy!!! everyone look how smart i am!! or how smart you think u are.
    the fix is SOOOOOOo easy!!! Cloning your MBP?
    you expect the comcast tech to know that? What Planet are u on….All you have to do is run a simple command from a dos prompt!!!! FIGURE IT OUT MR PERFECT!!!!!! LMAO Comcast is hiring!!!!
    Well this problem was only solvable by cloning the MAC address of my MBP to my router. Making the modem think that it is still talking to my MBP.

    Once we cloned the MAC address the router got an IP and we were on our way.

    Thank you Comcast for educating your techs on how to solve this issue with your craptacular

  32. January 11th, 2014 11:25 am LMAo

    You forgot to open at the top ()

  33. February 28th, 2014 2:39 am MCoate

    Again, you DO NOT need to clone anything here, that is ridiculously unnecessary. This is a router, with sticky MAC Addressing on its port. Refer to my post a couple above to see explanation,

    Unplug the cable modem(a minute or so should do), let it clear out its tables, plug the switch(or wireless AP) in FIRST, nothing else. The connect your other devices to it. Done. Working.

  34. September 21st, 2019 11:06 am Cortney Ison

    Hey very cool blog!! Man .. Beautiful .. Amazing .. I’ll bookmark your website and take the feeds also…I am happy to find so many useful information here in the post, we need develop more techniques in this regard, thanks for sharing. . . . . .

Your 2 cents: