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Networking The Internet

The IPv4 Internet Hiccups 248

New submitter pla writes: Due to a new set of routes published yesterday, the internet has effectively undergone a schism. All routers with a TCAM allocation of 512k (or less), in particular Cisco Catalyst 6500 and 7600's, have started randomly forgetting portions of the internet. 'Cisco also warned its customers in May that this BGP problem was coming and that, in particular, a number of routers and networking products would be affected. There are workarounds, and, of course the equipment could have been replaced. But, in all too many cases this was not done. ... Unfortunately, we can expect more hiccups on the Internet as ISPs continue to deal with the BGP problem." Is it time to switch to all IPv6 yet?
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The IPv4 Internet Hiccups

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  • by marka63 ( 1237718 ) <marka@isc.org> on Wednesday August 13, 2014 @08:36AM (#47662029)

    How much more gradual do you want? I've been running dual stack for over a decade with a tunnel back to HE. At this stage most of your equipment runs fine with IPv6.

  • Re:IPv6 (Score:2, Informative)

    by Anonymous Coward on Wednesday August 13, 2014 @08:47AM (#47662081)

    You have no idea what you are talking about. Two words: prefix aggregation.

  • Re:Betteridge (Score:3, Informative)

    by BitZtream ( 692029 ) on Wednesday August 13, 2014 @09:04AM (#47662163)

    Except that this has nothing to do with IPv6. IPv6 will do nothing to resolve this problem and will in fact make it worse because the problem itself is due to a router not having enough RAM and nothing about IPv6 results in less RAM usage.

    Sure, we should get on the IPv6 bandwagon, well, except it sucks right now and can lead to some annoying connectivity issues when sites are misconfigured, or setup IPv6 and then forget about it so you're trying to connect to an IPv6 address thats no longer used because no one bothered to update DNS ... or their IPv6 connection is through one of their shitty over saturated links.

    My ISP does IPv6, as does all my equipment. I had to disable it so that the rest of my family doesn't wonder why random sites don't work on their PC but work fine on their phone and while I can't remember the ones off to the top of my head, there are some big ones that regularly fuck up. Hell, even Google's IPv6 connectivity is shoddy at times.

  • Re:IPv6 (Score:2, Informative)

    by EvilJoker ( 192907 ) on Wednesday August 13, 2014 @09:05AM (#47662167)

    Why would that be different than with IPv4? Prefix aggregation, AKA route summary, AKA Supernetting, has been available for a very long time. Unless IPv6 addresses are being handed out in a way that's much more conducive to this, it won't really change anything. This guy agrees (#4) [cisco.com]

    Further, since IPv6 is a longer address, fewer can be stored. Per Cisco [cisco.com], the Catalyst 6500 can handle 1M IPv4 addresses, OR 512K IPv6 addresses (but not both simultaneously)

    (Yes, I know the Catalyst is a switch, not a router, and the summary is bollocks for confusing the two. It was, however, the first mention of it I found)

  • Re:Yes, Please (Score:2, Informative)

    by BitZtream ( 692029 ) on Wednesday August 13, 2014 @09:08AM (#47662189)

    If we had continued to keep the automobile speed limit at 10 mph year-after-year because a few lazy old farts refused to give up their goddamned horses and buggies, we'd still be driving around today at 10 mph.

    19 mph, because no one pulls you over for doing 9 over, but 10? You're in the pen!

  • Re:IPv6 (Score:5, Informative)

    by Dagger2 ( 1177377 ) on Wednesday August 13, 2014 @09:14AM (#47662219)

    Unless IPv6 addresses are being handed out in a way that's much more conducive to this, it won't really change anything

    Which they are, as a direct result of v6 being so huge. See RFCs 1715 and 3194 for discussion on this.

    Obviously in the long run we'll end up with a higher absolute count of routes in v6 (because supporting more people was the other reason for it) but the route count will scale far better than a network that has to be run at a ridiculously high HD-ratio because it's too small.

  • Re:Betteridge (Score:5, Informative)

    by Anonymous Coward on Wednesday August 13, 2014 @09:16AM (#47662231)

    One of the design goals of IPv6 was to reduce the size of the global routing table. That's why there are so many more addresses in IPv6 than there are ever going to be devices. Each provider gets so much address space that nobody needs to come back for more. That means there's no address space fragmentation due to address scarcity, like there is with IPv4, where providers usually have dozens or hundreds of separate allocations which can't be aggregated and must all be entered into the global routing table. IPv6 addresses are four times as long as IPv4 addresses, but there are far more than four times as many routing table entries per ASN with IPv4 than with IPv6

  • Re:Betteridge (Score:5, Informative)

    by devman ( 1163205 ) on Wednesday August 13, 2014 @09:46AM (#47662401)
    Also routing only occurs on the first 64-bits of an IPv6 address, the router doesn't need to store the host last 64-bits of an IPv6 address.
  • Re:Betteridge (Score:5, Informative)

    by Bengie ( 1121981 ) on Wednesday August 13, 2014 @09:52AM (#47662443)
    Core routers only use the first 48bits as that's the smallest block that is routable on the Internet. Which is why IPv4's /24 vs IPv6's /48 explains the routers supporting 1024K IPv4 routes or 512K IPv6 routes or a 512K/256K split. Exactly 2x difference. But IPv6 has sparse allocations resulting in about an effective 10x reduction in the number of routes.
  • I actually bought a new router within the last year. A "nice" Buffalo model with DD-WRT built in. Only to find out DD-WRT doesn't support native IPv6 (which my old, faulty NetGear did, go figure). They just support Toredo or other tunneled IPv6 solutions.

    Man, was I disappointed.

  • Re:Betteridge (Score:1, Informative)

    by Cramer ( 69040 ) on Wednesday August 13, 2014 @02:49PM (#47664873) Homepage

    ABSOLUTELY FUCKING WRONG IPv6 addresses are 128bits with a 128bit mask. Every bit counts.

    You have fallen to a classic blunder. Just because that bullshit SLAAC requires a 64bit prefix does NOT mean the whole damned world is 64+64. This idiot-assumption makes your entire product line completely useless; you have now bankrupt your company.

The best defense against logic is ignorance.