Re: [v6ops] SLAAC renum: Problem Statement & Operational workarounds

Fernando Gont <> Sat, 26 October 2019 18:24 UTC

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To: Brian E Carpenter <>, Mark Smith <>
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From: Fernando Gont <>
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Subject: Re: [v6ops] SLAAC renum: Problem Statement & Operational workarounds
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On 25/10/19 22:30, Brian E Carpenter wrote:
>>>     Renumbering is not "common" but it certainly happens.
> ....> People imply it is a regular and routine event...
> Sadly, it is. For example, at my previous apartment there was a badly waterproofed joint somewhere between me and the nearest street cabinet, so for months I frequently lost ADSL synch... and when it came back, I got new IPv6 prefix. After a heavy rainstorm, this would happen many times a day.
> Yes, OK, there was a copper cable fault and it took <unmentionable company> many months to fix it. OK, maybe the ISP shouldn't regenerate a prefix every time. But that's real life and I suspect I am one of millions.

Indeed you are. In fact, I presented this topic at a recent LACNOG
meeting, and we had at least three guys, from different countries,
coming to the mike, noting they have experienced this, noting that they
wished we did something about it. The document itself is a product of a
conversation with an ISP (from a completely different geographical zone).

Particularly when it's the user that experiences the problem, I think we
are not of much help when instead of improving robustness, we complain
about how the world should be a different places.

Fernando Gont
SI6 Networks
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