« on: March 14, 2017, 02:55:18 PM »
the issue is finally fixed in build 14393.953 (March CU update)
Welcome to Hurricane Electric's Tunnelbroker.net forums!
The fix should be expected to release with the March 20107 CU for 1607 clients if everything goes well.
So the fix for RS2 should be in the WIP builds, if not, should be in the next few build releases.
In regards to the RS1 code fix, we are targeting Q1 of 2017 as long as testing/validation are successful. Once I have an exact date and KB article, I will update this thread again.
For temporary workaround, would recommend to configure a startup script to do ipconfig /renew6 on the machines.
Thank you to the folks who have reached out to me with the logs and data. At this time, the product group is investigating further to determine root cause. I will update this thread as soon as I have some more information.EDIT: also reported in ipv6-ops mail list
Avatar of ARUDELL
ARUDELLMicrosoft (MSFT) 975 Point
I have noticed that on all my Windows 10 machines with the Anniversary Update, they no longer receive IPv6 DNS from DHCPv6 servers if network is configured for Stateless DHCP (Managed Flag unset, Other Flag Set in RA). They receive IPv6 information correctly if the network is configured for Stateful DHCP.https://social.technet.microsoft.com/Forums/windows/en-US/b16e7d78-e390-4ada-a24b-3ccba60fa571/no-ipv6-dns-statelessdhcp-since-windows-10-anniversary-update?forum=win10itpronetworking
It isn't just you. DNS servers aren't picked up after the AU via either RDNSS (which never worked) or stateless DHCPv6. Several others have made the same observation - something is clearly broken.
Today Apple released the first public seeds of iOS 9 and OS X El Capitan.
These seeds (and the third developer seeds released yesterday) include an improved version of Happy Eyeballs.
Based on our testing, this makes our Happy Eyeballs implementation go from roughly 50/50 IPv4/IPv6 in iOS 8 and Yosemite
to ~99% IPv6 in iOS 9 and El Capitan betas.
While our previous implementation from four years ago was designed to select the connection with lowest latency
no matter what, we agree that the Internet has changed since then and reports indicate that biasing towards IPv6 is now
beneficial for our customers: IPv6 is now mainstream instead of being an exception, there are less broken IPv6 tunnels,
IPv4 carrier-grade NATs are increasing in numbers, and throughput may even be better on average over IPv6.
The updated implementation performs the following:
- Query the DNS resolver for A and AAAA.
If the DNS records are not in the cache, the requests are sent back to back on the wire, AAAA first.
- If the first reply we get is AAAA, we send out the v6 SYN immediately
- If the first reply we get is A and we're expecting a AAAA, we start a 25ms timer
- If the timer fires, we send out the v4 SYN
- If we get the AAAA during that 25ms window, we move on to address selection
- When we have a list of IP addresses (either from the DNS cache or by receiving them close together with v4 before v6),
we perform our own address selection algorithm to sort them. This algorithm uses historical RTT data to prefer addresses
that have lower latency - but has a 25ms leeway: if the historical RTT of two compared address are within 25ms of each
other, we use RFC3484 to pick the best one.
- Once the list is sorted, we send out the SYN for the first address and start timers based on average and variance of the
historical TCP RTT. Roughly speaking, we start the second address around the same time we send out a SYN retransmission
for the first address.
- The first address to reply with a SYN-ACK wins the race, we then cancel the other TCP connection attempts.
If this behavior proves successful during the beta period, you should expect more IPv6 traffic from Apple products in the future.
Note however that this only describes the current beta and all these details are subject to change.
Please test this out if you have the means to, we'd love to see test results and receive feedback!
I would like to personally thank Jason Fesler and Paul Saab for their help investigating these issues and testing this.
CoreOS Networking Engineer