On 11/28/21 14:58, Masataka Ohta wrote:
Exactly.
That facebook poorly managed their DNS to cause the recent disaster is an important evidence to support my point that DNS, so often, may not be helpful for network operations against disastrous failures, including, but not limited to, DNS failures.
Yes, but that does not mean that DNS is not valuable, or cannot be hardened. Everything can break, even an IPv4 interface on a router port. Good practice in network operations is what keeps these kinds of problems at bay. I mean, why else do we have lists like these? I am certain Facebook have hardened their DNS infrastructure, and that particular failure scenario should not recur, given all the clever people there, and around them.
There was a time when knowing the IP(v4) address of every interface of every router in your network was cool.
I surely acknowledge your point that it is impossible to do so with MAC address based IPv6 addresses, which is why IPv6 opex is so high.
But, with manually configured IP addresses, it is trivially easy to have a rule to assign lower part of IP addresses within a subnet for hosts and upper part for routers, which is enough to troubleshoot most network failures.
That's just satisfying one's mental (or emotional) nits. Routers (and customers) don't care about how anally we assign address space. As long as it is compliant, does not conflict, and is correctly routed. That we cannot transpose our IPv4 mental/emotional habits on to IPv6 does not make IPv6 more complicated. It just makes us more stuck in our ways. After all, DHCPv6 still does not offer a default gateway.
So, you are saying you haven't faced real operational problems to loss DNS information for these 15 years.
Congratulations for your luck!
I am sure I have had a DNS issue of some sort or other in the past 15 years. The fact that I can't remember what it was is telling.
Surely, the recent disaster of facebook happened in the recent past.
So what?
And they have learned from it, and I dare say, fixed it. Facebook will neither be disposing of DNS any time soon, nor will they be dropping IPv6. Mark.