Unable to access fly.io web and API over IPv6

Hello,

I am not able to access fly.io web OR even the API which client is using. It works fine on IPv4.

My IPv6: 2402:c4c0:2::/48 

curl for web over IPv6:

curl -6 -v https://fly.io
*   Trying 2a09:8280:1::a:791:443...
* Connected to fly.io (2a09:8280:1::a:791) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
*  CAfile: /etc/ssl/cert.pem
*  CApath: none
* (304) (OUT), TLS handshake, Client hello (1):
* error:02FFF036:system library:func(4095):Connection reset by peer
* Closing connection 0
curl: (35) error:02FFF036:system library:func(4095):Connection reset by peer

curl for API over IPv6:

curl -6 -v https://api.fly.io/graphql
*   Trying 2a09:8280:1:f28:246e:d6a:949:dbbf:443...
* Connected to api.fly.io (2a09:8280:1:f28:246e:d6a:949:dbbf) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
*  CAfile: /etc/ssl/cert.pem
*  CApath: none
* (304) (OUT), TLS handshake, Client hello (1):
* error:02FFF036:system library:func(4095):Connection reset by peer
* Closing connection 0
curl: (35) error:02FFF036:system library:func(4095):Connection reset by peer

trace to API end point:

mtr -wr api.fly.io
Start: 2022-08-31T04:42:36+0530
HOST: Anurags-MacBook-Pro.local         Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- router01.rtk.anuragbhatia.com      0.0%    10    2.0  20.2   1.9 158.3  48.8
  2.|-- router01.bom.anuragbhatia.com     10.0%    10   32.7  38.0  32.7  70.6  12.3
  3.|-- host01.bom.anuragbhatia.com        0.0%    10   32.8  34.1  32.8  35.9   1.0
  4.|-- ctpl-demarc.bom.anuragbhatia.com   0.0%    10   36.4  35.0  33.8  36.4   0.8
  5.|-- 2404:a800:7a00::a1                 0.0%    10   34.4  36.4  33.9  52.3   5.6
  6.|-- 2404:a800:0:4::23                  0.0%    10  130.9 132.6 129.4 147.5   5.5
  7.|-- decix6.as36236.net                 0.0%    10  157.8 191.5 156.8 498.2 107.8
  8.|-- 2a00:dd80:20:13::3                 0.0%    10  150.6 176.3 149.3 386.3  74.0
  9.|-- 2a09:8280:1:f28:246e:d6a:949:dbbf  0.0%    10  149.3 176.9 149.3 417.9  84.7

IPv4 works fine and in expected manner. TCP terminates locally at MAA / Chennai, India for IPv4.

Interesting.

nb, Fly’s network once had ipv6 connectivity issue due to misdiscovered (?) MTUs: IPv6 PMTUD issue - #3 by wjordan

Thanks for looking into it. Still getting the same issue.