Two *.olsr domain name fixes #406
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Queries for *.olsr should never be forwarded to public resolvers. Some resolvers drop queries for unknown TLDs, without a response. As a result, our query waits for a long time and eventually times out. This affects A queries for unknown hosts, and also all AAAA queries. Happy Eyeballs means an AAAA query is sent almost always, even though *.olsr is really only used for our IPv4 networking, and so we get lots of very slow DNS queries... This can be avoided very simply by not forwarding .olsr queries.
Previously, dnsmasq would only pick up our own .olsr domain names once OLSR had first flushed its nameservice hosts file, and once dnsmasq actually reloaded its config. This could take up to 5 minutes. Until then, our own .olsr domains were not resolvable. We now explicitly tell dnsmasq about our own .olsr domain names. As a result, they can be resolved instantly once dnsmasq is running. Neat side effect: proper .olsr hostnames in Reverse DNS and traceroute. Before this patch, the first hop would only report as 'frei.funk'.
| @@ -13,6 +13,7 @@ config dnsmasq | |||
| option noping '{{ dhcp_no_ping|int if dhcp_no_ping is defined else 1 }}' | |||
| option quietdhcp '1' | |||
| option cachesize '{{ dns_cache_size | default(10000) }}' | |||
| list server '/olsr/' | |||
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Can you explain the config syntax? I don't understand why this config option should exclude olsr domains from a lookup.
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I found it: https://openwrt.org/docs/guide-user/base-system/dhcp_configuration#selective_dns_forwarding
Probably you could also do list server '/olsr/127.0.0.1'
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Probably you could also do list server '/olsr/127.0.0.1'
That might do a loop, /olsr/ simply means that *.olsr lookups are forwarded to a "null server" if we don't already know the answer, i.e. they're not forwarded at all.
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If OLSRd served a local DNS server on e.g. port 10053 instead of writing files, we could set it to /olsr/127.0.0.1#10053 instead of refreshing files.
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If OLSRd served a local DNS server on e.g. port 10053 instead of writing files, we could set it to
/olsr/127.0.0.1#10051instead of refreshing files.
That would probably solve OLSR/olsrd#116 along the way.
dnsmasq: define .olsr domains independently of OLSRd
dnsmasq: never forward .olsr queries to public resolvers