There is still something very weird going on. My IPv6 BQM graph is now showing substantial amounts of blue (average latency increase) as well as tons of yellow (peak latency), but I don't really notice anything wrong in practice.
Testing with pings, to Google IPv6 it's as flat as a pancake at 5ms latency:
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6 | root@nuc1:~# ping6 -q -c100 -i0.1 2001:4860:4860::8888
PING 2001:4860:4860::8888(2001:4860:4860::8888) 56 data bytes
--- 2001:4860:4860::8888 ping statistics ---100 packets transmitted, 100 received, 0% packet loss, time 9943ms
rtt min/avg/max/mdev = 4.981/5.175/5.390/0.125 ms |
But to the BQM server it's terrible: average latency 33ms and highly variable
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| root@nuc1:~# ping6 -q -c100 -i0.1 -c500 2a02:68:1::164
PING 2a02:68:1::164(2a02:68:1::164) 56 data bytes
--- 2a02:68:1::164 ping statistics ---500 packets transmitted, 500 received, 0% packet loss, time 50184ms
rtt min/avg/max/mdev = 4.357/33.327/115.437/19.528 ms, pipe 2root@nuc1:~# |
Trying to another destination, one of bytemark's nameservers:
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6 | root@nuc1:~# ping6 -q -c100 -i0.1 a.ns.bytemark.co.uk.
PING a.ns.bytemark.co.uk.(a.ns.bytemark.co.uk (2001:41c8:2::3)) 56 data bytes
--- a.ns.bytemark.co.uk. ping statistics ---100 packets transmitted, 100 received, 0% packet loss, time 9977ms
rtt min/avg/max/mdev = 9.607/9.827/10.132/0.164 ms |
That's perfectly flat too (higher average latency, since their data centre is further up North, but that's just the laws of Physics)
I can't help thinking that:
1. This is nothing to do with Cerberus' BRASes - since a BRAS problem would affect all destinations, not just some
2. It must be a network problem do with transit to specific sites only (including TBB BQM)