Re: [v6ops] A common problem with SLAAC in "renumbering" scenarios

Fernando Gont <fgont@si6networks.com> Thu, 31 January 2019 12:18 UTC

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To: JORDI PALET MARTINEZ <jordi.palet@consulintel.es>, Mikael Abrahamsson <swmike@swm.pp.se>
Cc: IPv6 Operations <v6ops@ietf.org>, "6man@ietf.org" <6man@ietf.org>
References: <60fabe4b-fd76-4b35-08d3-09adce43dd71@si6networks.com> <alpine.DEB.2.20.1901311236320.5601@uplift.swm.pp.se> <A03364DB-B179-43AD-B509-21A429BD3A41@consulintel.es>
From: Fernando Gont <fgont@si6networks.com>
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Date: Thu, 31 Jan 2019 09:18:26 -0300
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Subject: Re: [v6ops] A common problem with SLAAC in "renumbering" scenarios
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On 31/1/19 08:57, JORDI PALET MARTINEZ wrote:
> Exactly, this is the reason why 99% of the CEs don't save this data in the flash, because it is prone to creating troubles and bringing the CE to a "brick" state.
> 
> I've seen that several times, having for example statistics written in the internal router flash, easily will break the router, 

Yes, this has been my point while discussing these issues while working
on the I-D.


> or at least needed a factory reset or something similar. Alternatively using a "good quality" USB stick to save this kind of data, avoids the problem 
>(most of the time, because from time to time I've got also good USBs
being damaged after some months of usage).

Same here. I run a lot of Raspberry Pis for measurement purposes, and
quite often the SD cards get damaged.


> 
> I think for example, RIPE Atlas get the same problem from time to time, so the USBs get wrong. Sometimes reformatting is sufficient, but not always.
> 
> Mandating that in low cost CEs will mean CEs are no longer "low cost", unless new "safe" opensource ways to keep the flash are available and can be included in new firmware releases.

FWIW, i don't think mandating this is the way to go. We were not sure
whether to make this a MUST (and then CPEs might claim whether they
comply with this spec or not), a SHOULD, or have no normative language.

I guess we could elaborate a bit more about the CPEs, discuss why it may
not be feasible to do this, and s/MUST/SHOULD/. What do you think?

Thanks!

Cheers,
-- 
Fernando Gont
SI6 Networks
e-mail: fgont@si6networks.com
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