It appears that IPv6 is 'broken' when using thunderbolt-net connections. ICMPv6 works.
Repro ------- - Take two machines each with debian on them with a thunderbolt TB4 connection. - Ensure there are no IPTABLES filtering rules in place - configure ssh to listen on all ports, all protocols - Connect the two machines with a TB cable. - Statically address each interface on each machine with an IPv6 address in the same subnet - ping machine 1 IPv6 from machine 2 (this will work) - try to ssh from machine 1 to machine 2 using IPv6 (this will not work) note: this seems to affect other traffic other than SSH too (like ceph cluster traffic) This has been reproduced on promox ve 8 and vanilla debian 12 (by two people) Also on the same machines i repeated the same steps with a direct connected ethernet cable and had zero issues (in my mind this validates the basic configuration is ok). This is my first time using a mailing list, so apologies if i have taken the wrong approach. alex
