[homeassistant.components.ssdp] Failed to setup listener for fe80::60e2:2d3d:142c:a92e: [Errno -2] Name does not resolve

Configuration
1

I configured my HA to run on multiple interfaces (2 to be exact).
These interfaces are given IPv4 & IPv6 addresses by the DHCP.

However some of these IP’s (seem only to be the local IPv6 addresses) render warnings in my logs:

2022-01-04 15:55:39 WARNING (MainThread) [homeassistant.components.ssdp] Failed to setup listener for fda8:1129:473c::db2: [Errno -2] Name does not resolve
2022-01-04 15:55:39 WARNING (MainThread) [homeassistant.components.ssdp] Failed to setup listener for fe80::60e2:2d3d:142c:a92e: [Errno -2] Name does not resolve
2022-01-04 15:55:39 WARNING (MainThread) [homeassistant.components.ssdp] Failed to setup listener for fe80::6a96:2e14:4ed4:c46a: [Errno -2] Name does not resolve

Running trace of core and ssdp does not provide any additional troubleshooting information.

Anyone else facing this ?

2

Are they also set up in DNS? If not that is where the errors originate. They need names in DNS in order to resolve.Some DNS servers have an option to automatically update DNS.

3

Why should HA bother about DNS resolution of its own host… ?
I’ve setup my DNS to resolve to the public IP’s, but I can’t restrict HA to only listen to those, it will automatically attempt to listen on all assigned IP’s of the interface.

In addition, some local IP’s may vary depending on the DHCP server. Hence maintaining the DNS would be a nightmare.

4

That is part of the network functionality of the OS so you do not need to memorize ip addresses for all the Internet sites you visit, for instance. DNS names are MUCH easier to remember & type,

5

I’m aware of all that… i’ve setup my own DNS with master forward and reverse zones…
But HA running on a host should not care about reverse lookups of its own IPs…

6

Here is one reason for reverse DNS lookups. Remember the host OS generally does monitoring, not necessarily HA although it can specify WHAT to monitor.

  • System logging or monitoring tools often receive entries with the relevant devices specified only by IP addresses. To provide more human-usable data, these programs often perform a reverse lookup before writing the log, thus writing a name rather than the IP address.
7

As a former directory services engineer i vehemently disagree.

ALL problems are name resolution problems until proven otherwise…

What a developer needs wuth a particular name resolution is immaterial, they asked, it wasnt provided. Error happens.

If you want to use an address space you need to be prepared to resolve DNS for any records you name in that address space even if its just a hosts file doing the lookup. The solution is to either provide DNS for that IPv6 subnet or eliminate tbe address.

1 Like
8

I wholeheartedly concur. I spent 2 weeks in DNS training by an instructor who later went to reorganize the root nameservers. The error refers to name resolution ( DNS) which is not happening.

9

So I did some further digging by performing some traces…
I’ve ran a tcpdump -i any port 53 on the hassio_dns container and my external DNS server.

I can say with 100% certainty, that there is no reverse lookup for the mentioned IPv6 addresses…
hence it doesn’t sound like a DNS issue…

10

There were some IPv4 / IPv6 related issues patched in 2021.12.8 You might want to try updating.

11

Already running that version

12

I’ve now setup all zones and reverse zones for all the IPv6 addresses mentioned… doing nslookup on each of them does properly return a hostname, hence all are now resolvable.
Still I get these warnings in my logs…

Any further suggestions from anyone?