Cloudflare (AS13335) broken - only on IPv6?

ignatios at ignatios at
Thu Jan 24 14:22:39 CET 2019


we've got reports that 

- (104.17.N.77, 2606:4700::ip.v4.adr.ess)

(and later:
- (104.24.10[23].152, 2606:4700:30::6818:6[6]98)
- (104.25.17[45].13, 2606:4700:20::6819:a[ef]0d)

"don't work but work when IPv6 is switched off"

Careful scrutinizing revealed that this was only the case for one
or two of the used address group.

Detailed symptom: TCP opens, but the first data segment written
gets a RST back.

I first reported to, but it seems to be a generic
problem to me now (who else is seeing this?)

So, if any colleague @ cloudflare (AS13335) reads this: 
please make work again.

Ignatios Souvatzis, Chief IPv6 enabler		RFC 6540
Gemeinsame Systemgruppe b-it + Informatik	Tel. +49 228 73-60701
gsg at

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