# SyncThing Relay Not Binding to IPv6 on OpenBSD
**URL:** https://forum.syncthing.net/t/syncthing-relay-not-binding-to-ipv6-on-openbsd/24150
**Category:** Support
**Created:** [April 11, 2025, 8:01am UTC](https://forum.syncthing.net/t/syncthing-relay-not-binding-to-ipv6-on-openbsd/24150 "2025-04-11T08:01:11Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@myusername](https://forum.syncthing.net/u/myusername)
#### Post date: [April 11, 2025, 8:01am UTC](https://forum.syncthing.net/t/syncthing-relay-not-binding-to-ipv6-on-openbsd/24150/1 "2025-04-11T08:01:11Z")
I’ve been running a relay for this for quite a while, probably years, on OpenBSD. Two days ago it stopped working and I’ve been down a bit or a rabbit hole debugging.
I think there are two things.
Firstly -protocol tcp (which is default) doesn’t bind to an IPv6 address and neither does “-protocol tcp6” - is this a bug with the OpenBSD AMD64 build?
Secondly -protocol tcp4 doesn’t prevent the relay from trying to join using it’s IPv6 endpoint, so you get something like:
2025/04/09 13:50:28 pool.go:87: Failed to join [https://relays.syncthing.net/endpoint:](https://relays.syncthing.net/endpoint:) request or check error
2025/04/09 13:50:28 pool.go:88: Response data: getting invitation: dial tcp [2001:8b0:f10:IPREMOVED::::338e]:22067: connect: connection refused (It’s refused because it never opens an IPv6 listen port)
If you specify your external IP with -ext-address xxx.xxx.xxx.xxx:22067 you get:
2025/04/09 14:38:11 pool.go:22: Joining [https://relays.syncthing.net/endpoint](https://relays.syncthing.net/endpoint)
2025/04/09 14:38:11 pool.go:98: Failed to join [https://relays.syncthing.net/endpoint:](https://relays.syncthing.net/endpoint:) IP address not matching external address
I think what’s happened is that:
[https://relays.syncthing.net/endpoint](https://relays.syncthing.net/endpoint) now resolves both as IPv4 and IPv6
I manually downloaded the latest build v1.29.4 and that doesn’t bind to IPv6 either and still tries to register it’s IPv6 IP when you specify -protocol tcp4
I assume “-protocol tcp4” only influences the listenning part and registering the endpoint does a gethostbyname and if IPv6 is working uses that to connect to the relay registry?
My work around for today was to build a fresh VM and not enable IPv6 on it and that’s restored the relay.
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### Author:  [@bt90](https://forum.syncthing.net/u/bt90)
#### Post date: [April 11, 2025, 10:27am UTC](https://forum.syncthing.net/t/syncthing-relay-not-binding-to-ipv6-on-openbsd/24150/2 "2025-04-11T10:27:01Z")
Are IPv6 relays even a thing?
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### Author:  [@myusername](https://forum.syncthing.net/u/myusername)
#### Post date: [April 11, 2025, 10:36am UTC](https://forum.syncthing.net/t/syncthing-relay-not-binding-to-ipv6-on-openbsd/24150/3 "2025-04-11T10:36:47Z")
Yes. but that’s not my point. my point is, if you have an IPv6 host you can’t run a relay, any relay.
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### Author:  [@bt90](https://forum.syncthing.net/u/bt90)
#### Post date: [April 11, 2025, 10:57am UTC](https://forum.syncthing.net/t/syncthing-relay-not-binding-to-ipv6-on-openbsd/24150/4 "2025-04-11T10:57:30Z")
Oh, that’s a bug for sure.
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### Author:  [@AudriusButkevicius](https://forum.syncthing.net/u/AudriusButkevicius)
#### Post date: [April 12, 2025, 11:18pm UTC](https://forum.syncthing.net/t/syncthing-relay-not-binding-to-ipv6-on-openbsd/24150/5 "2025-04-12T23:18:34Z")
Worth opening on github
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### Author:  [@calmh](https://forum.syncthing.net/u/calmh)
#### Post date: [April 18, 2025, 2:43am UTC](https://forum.syncthing.net/t/syncthing-relay-not-binding-to-ipv6-on-openbsd/24150/6 "2025-04-18T02:43:37Z")
We used to only have an A record and no AAAA on relays.s.n, that changed somewhere during all the migrations I’m doing but probably worth reverting. I think v6 only public relays are not enormously useful.
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### Author:  [@danhusan](https://forum.syncthing.net/u/danhusan)
#### Post date: [April 18, 2025, 5:02am UTC](https://forum.syncthing.net/t/syncthing-relay-not-binding-to-ipv6-on-openbsd/24150/7 "2025-04-18T05:02:26Z")
I see the AAAA is gone now and my (linux) relay is back online again, thanks!
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### Author:  [@myusername](https://forum.syncthing.net/u/myusername)
#### Post date: [April 22, 2025, 8:41am UTC](https://forum.syncthing.net/t/syncthing-relay-not-binding-to-ipv6-on-openbsd/24150/8 "2025-04-22T08:41:23Z")
Thanks for that - was away over the weekend, without email but noticed the number or relays bump up to over 700 again.
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### Author:  [@system](https://forum.syncthing.net/u/system)
#### Post date: [May 22, 2025, 8:41am UTC](https://forum.syncthing.net/t/syncthing-relay-not-binding-to-ipv6-on-openbsd/24150/9 "2025-05-22T08:41:34Z")
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