
IPv6 Multi WAN madness - gerdesj
IPv6 is seemingly predicated on a single link - your prefix is delivered from a single ISP which is not generally under your control, unless you buy Provider Independent addresses and use BGP peering with multiple providers.<p>How do you deal with bootstrapping and effectively running a IPV6 network under these conditions without resorting to PI?  How do you migrate from one ISP to another?
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jlgaddis
Router advertisements!

You may consider using RFC4193 addresses inside your network.

There's also NPT but that's basically NAT which I, personally, recommend
avoiding if at all possible.

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gerdesj
Ta for replying.

I have already deployed ULA (and discovered a few wrinkles) and NPT is the
only game in town for getting multiple WANs to work. You _may_ recommend
against it (I hate NAT too) but what is the alternative?

For example, you are a small business (say <£1M t/o pa) You have a 80/20MBs-1
FTTC (UK - VDSL, copper last mile) internet connection and you want to get
some sort of redundancy/backup for your internet connection. So you get
another line in at the same rate. In the UK, we pay around £30-£40 per month
for this (if it is available.)

So, ISPa gives me a prefix and ISPb gives me another prefix. My router, via
SLAAC, causes various addresses to become available but my endpoints are
stupid - OK they do not know what to do because they are not routers. Knock
out ISPa and they will not automatically fail over to ISPb. Nor will they do
the really best thing and use both ISP links simultaneously.

I understand IPv6 very, very deeply (I've used it for years) and it is
wanting. To be fair, the addressing scheme is spot on but the ISP addressing
model is badly wrong and absolutely right at the same time (depending on who
you are).

If you have a multiple GB connection and a /48 prefix through a 99.999%
trusted supplier or a home grade VDSL link that you don't even know what is
happening, then all is probably OK for IPv6. I look after rather a lot of
people and businesses that don't come into those categories.

Is NpT really the best that IPv6 has to offer?

