The Tor developers should check if this is a currently unsupported functionality or a bug.
Hello @Dosee, it seems a bug. I created a ticket for this issue. Meanwhile, you can disable your relay IPv6.
Thank you very much
Same problem here behind my AVM Fritzboxq
Nov 25 13:57:23 xxx Tor: Auto-discovered IPv6 address [2003:xx:270a:e300:xx37:2622:a0d9:xxx]:9852 has not been found reachable. However, IPv4 address is reachable. Publishing server descriptor without IPv6 address. [2 similar message(s) suppressed in last 2400 seconds]
is there already a solution?
Thanks and greetings from Bavaria
No, you can disable IPv6 for now.
You actually can run a relay with a dynamic IPv6 prefix. I do it with CenturyLink GPON 6rd:
However, you need to do one of the following:
- Allow incoming connections to your relay ORPort in your router
- Use a static, non-privacy extensions SLAAC, and open up the suffix
Point 1 is likely easier and will work with most firewalls.
Point 2 can be done on Linux-based firewalls like OpenWrt and VyOS and many consumer-level routers, but not BSD-based firewalls like pfSense and OPNsense. Commercial routers may vary, I believe MikroTik and Ubiquiti do allow IPv6 suffix, but maybe not Juniper or Cisco.
If your router is using Point 2, FreeBSD has static SLAAC by default but Linux/OpenBSD/Windows use privacy extensions so in the very likely latter case, disable privacy extensions.
My ipv6 suffix is generated using the EUI64 method (based on MAC address), but the relay is still going offline whenever the ISP sends me a new prefix. Shouldn’t this be working then? Or maybe I misunderstand what point 2 is about.
My router runs OpenWrt, by the way.
I assume your ISP uses DHCP and DHCPv6-PD looking at your message. I use PPPoE with 6rd so my experience is different.
Assuming you aren’t running a relay on Windows, one thing you could do is make a cron script (Linux/BSD/Mac) or systemd timer (Linux-only) that checks if the IPv6 has changed, and if so, restarts Tor.
I can’t code one up, sorry. If you were to code one up, make sure it runs every minute, but not so frequent or so infrequent (to avoid downtime).
I’m not sure how it works on the ISP side, but my router is using SLAAC, definitely not DHCPv6. I also connect via PPPoE.
Sorry for the late reply.
I don’t know if “router” means Tor relay or your NAT/PPP router, so I am assuming your Tor router uses SLAAC.
Your PPPoE session, usually a Wi-Fi router, ISP gateway, pfSense or Ubiquiti box uses DHCPv6-PD on top of the PPPoE session to assign a prefix to your LAN, which in turns assigns the SLAAC to your Tor server.
Some ISPs such as CenturyLink use 6rd instead of DHCPv6-PD on top of PPPoE.
Are you worried that your IPv6 prefix changes so often? If so, a Hurricane Electric IPv6 tunnel is a good choice for your relay while you use your ISP IPv6 for everything else.
The OpenWrt wifi router (which makes the PPPoE call) has these options set:
dhcp.lan.ra='server' dhcp.lan.ra_slaac='1' dhcp.lan.ra_flags='managed-config' 'other-config' dhcp.lan.dhcpv6='disabled'
That’s what I meant.
sorry that I’m answering so late. My now working solution is to use a script in combination with ddclient. Every time the ddclient detects a change of the ipv6 it automatically restarts the tor service. that is atm a working solution for me. the downsite is, that my relay has a much shorter uptime.