Pinging c.root-servers.net (2001:500:2::c) via Frankfurt tunnel does not work

[Zandalari]

When I try to ping c.root-servers.net (2001:500:2::c) it ends at 2001:470:0:69::1 (ve399.core1.fra1.he.net).

1  [private] 0.350 ms  0.505 ms  0.611 ms
2  [private.tunnel.tserv6.fra1.ipv6.he.net] 34.272 ms  34.217 ms  34.220 ms
3  ve399.core1.fra1.he.net (2001:470:0:69::1)  38.999 ms  39.004 ms  38.996 ms
4  * * *
5  * * *
6  * * *
7  * * *
8  * * *
9  * * *
10  * * *
11  * * *
12  * * *
13  * * *

Pinging from native IPv6 works, of course.

1  [private]  0.821 ms  0.796 ms  0.69 ms
2  2a01:7e01:2::2 (2a01:7e01:2::2)  0.682 ms * *
3  2001:978:2:7::7b:1 (2001:978:2:7::7b:1)  1.387 ms  0.94 ms  0.95 ms
4  be2501.ccr41.fra03.atlas.cogentco.com (2001:550:0:1000::9a36:27b1)  1.386 ms  1.244 ms  1.266 ms
5  be2533.agr22.fra03.atlas.cogentco.com (2001:550:0:1000::8275:309d)  1.516 ms  1.454 ms  1.435 ms
6  2001:978:2:7::1a (2001:978:2:7::1a)  1.061 ms  0.957 ms  1.002 ms
7  c.root-servers.net (2001:500:2::c)  0.797 ms  0.837 ms  0.854 ms

[trevorwarwick]

This happens via tun5.lon1 as well - not sure it's ever worked.  I wouldn't have noticed, but it's a built-in test on  the Ripe Atlas probe I'm hosting.

[broquea]

That server is single-homed behind a network that doesn't have any routes back to Hurricane Electric.