Homey Community Forum

Tado insane DNS lookups

#1

Unless my Pi-hole DNS server is wrong, the Tado App on my Homey makes 200.000 DNS requests per 24 hours.

Anyone else noticed this?

#2

Not myself but I’ve seen reports in the past where numerous requests for a Philips Hue were done (meethue.com if I remember correctly)
You would expect some dns caching, the ttl on the my.tado.com record is 60 seconds but if your numbers are correct there are (averaged) over 2,3 requests per second and not the 1 per 1440 seconds if the ttl was honored.

#3

I don’t have a tado, but my homey is doing most DNS requests in my environment. I’m working from home and am constantly online, but still the homey does a lot more requests (I now realize it could have something to do why my working pace…).

Most requests within my env go to api.ring.com… so maybe its normal behavior?

#4

Do you have numbers? How many requests are we talking about? api.ring.com has a 5 minute ttl so anything above 288 requests in 24 hours does indicate something fishy is going on with caching of dns information.

#5

there you go

#6

My Homey does also 2 DNS requests each 5 seconds to api.ring.com, 1440 requests each hour. In my opinion there is no way to change this because this is programmed behaviour in the Ring app.

#7

Well yeah, trying to connect to api.ring.com may be programmed to happen 2 times in 5 seconds, but when a request is made and the dns info is retrieved I would not expect another dns request until the ttl on the record expires, I would expect the info to be cached so no new dns query is required.

#8

TTL of 60 seconds… But why?

#9

load balancer?

#10

But thats on the server side, doesn’t have anything to do with a client not doing any caching.
Maybe it’s because apps are sandboxed and there’s no method for caching implemented.

#11

Should be done on OS-level. But the DNS-lookups aren’t an issue in itself, calling the API (using the DNS-lookup) that much is the real issue I think. I did see an app with DNS-caching iirc, I’ll look it up tonight…

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#12

Many clients don’t do DNS caching, they just continue querying the DNS server. The DNS server will probably honor the caching ( so the pi-hole will not forward the DNS query to an outside resolver) .

This is a nice overview of honoring TTL caching: https://www.ctrl.blog/entry/dns-client-ttl

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#13

Yes, here as well. Pi-hole logs an incredible number of DNS requests to tado home base.

#14

In the Release Notes for Homey v2.1.2-rc.3

  • [Core] DNS TTLs are now respected and cached
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