To clear IP addr., do I need to unplug the cable modem or the router?

Discussion in 'Networking & Security' started by Happy Hopping, Nov 19, 2010.

  1. Happy Hopping

    Happy Hopping [H]ardness Supreme

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    I try IPconfig release and renew, it seems only to renew the cable modem IP addr., and my router still uses the same dynamic IP addr. How do I clear and renew that IP addr.?

    I use a Linksys router, and in its software, there doesn't seems to be a function to release the router's IP addr.
     
  2. alphanumeric

    alphanumeric Gawd

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    Try rebooting or power cycling the router and modem. May or may not work depending on your ISP. I have a dynamic IP on my cable modem but my WAN IP address hardly ever changes. If it doesn't change there isn't much you can do other than calling your ISP and asking them to change. They are likely going to ask why you want it changed.
     
  3. MavsX

    MavsX [H]ard|Gawd

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    yeah, typically you can't just get a new public IP address...mine changes every so now and then..but in reality..it's a pain in the ass when it changes...ideally we'd all be able to keep the same public IP..without having to purchase static ip's.

    make sense?
     
  4. /usr/home

    /usr/home [H]ardness Supreme

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    You could change the WAN MAC address and that would force it to get a new IP. Not sure if you can do that on stock Linksys firmware though... with DDWRT you can.
     
  5. YeOldeStonecat

    YeOldeStonecat [H]ardForum Junkie

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    IPCONFIG command on your computer will only release and renew your computers local address, which is governed by your router and its private IP range (192.168.1.100 for example), via your routers DHCP service. Not related to your public IP address what-so-ever.

    You can log into your routers web admin, example...http://192.168.1.1, go to its WAN settings...and most will have a "release/renew", or "disconnect/connect" option if the WAN port is set to "obtain auto/dhcp" like most usually are for cable modem setups. This may or may not get you a different public IP address on your routers WAN interface...it depends on your ISP, which node your on load on the local DHCP service for your node, your ISPs DHCP lease time, etc etc.

    Sometimes if you unplug the power for your router....wait a few hours, and then plug it back in...you may get a new IP address, or not.

    Sometimes power cycling your cable modem can help get a new public IP address
    Sometimes powering down your modem and router...waiting several hours.....and then powering back up again...will get you a new public IP address.

    It all depends....on those factors I mentioned above. If a quick power cycle doesn't do it...power down and wait a while, you'll usually get a fresh new IP.

    I wouldn't mess with MAC spoofing....you risk the chance of picking a MAC address that someone elses router is using..and you'll cause problems for them...why be selfish and do that to someone else? Just do it the right way.
     
  6. Happy Hopping

    Happy Hopping [H]ardness Supreme

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    I already try the unplug trick several times last night. Supposedly, once I unplug, if some1 else grab my IP addr., then I will be auto-reassign a new 1. But I only unplug for 10 min. I'll try the 192.168.1.1 trick later today and see what happens.

    Thanks everyone
     
  7. Happy Hopping

    Happy Hopping [H]ardness Supreme

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    Update:

    I just try it at the admin mode in the router. There is a renew / rel. But after I release it, and wait for a few min., I renew it, and got back the same IP addr.

    I supposed I can wait longer, but I'm guessing it won't make much of a difference
     
  8. YeOldeStonecat

    YeOldeStonecat [H]ardForum Junkie

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    So your lease wasn't up yet, from your ISP. You can't control that, but basically you have to release the IP long enough to pass your lease expiration time, and then wait for some other customer of your ISP on your node to pull your old IP...and then you can get a new one.

    Curious though, why the insisting of a new public IP? Usually people desire the same one.
     
  9. Happy Hopping

    Happy Hopping [H]ardness Supreme

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    I am downloading some files in the internet. Ea. file requires 45 min. of wait time before I can grab the next 1
     
  10. YeOldeStonecat

    YeOldeStonecat [H]ardForum Junkie

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    That sounds like...some of the free "view pirated movies" websites out there.
    Might want to check out this thread
    http://hardforum.com/showthread.php?t=1563478
     
  11. ghost6303

    ghost6303 2[H]4U

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    DHCP lease times are almost always way longer then 45 minutes, so even if its possible to change your IP, it wont help you here.
     
  12. djBon2112

    djBon2112 [H]ardness Supreme

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    It also sounds like Rapidshare and just about every other POS download site people use. I hate them with a passion. I have to look at a wall of ads AND wait to download AND wait MORE to download the second part of a ROM!? :mad:

    OP, you may have a static IP from your ISP, in which case, you're SOL. Cable is usually static (as in, the lease is very long, sometimes in the months or years), DSL is usually dynamic (as in, the lease is very short, sometimes a few days or a week), but from what I know about PPPoE, you can get a new IP pretty much every time you connect, or at least that's how it is with Bell's DSL.

    The best test is powering off the modem and router for 30 minutes and starting them again.
     
  13. Happy Hopping

    Happy Hopping [H]ardness Supreme

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    No, I didn't pay for static IP package. It's definitely dynamic. I use this computer during the day, and in the evening, so in the end, 45 min. gap is no big deal