Using nscd to reduce DNS lookups with stats scripts (v28 image)

Hi all,

I run pihole on my LAN and see DNS lookups to adsbexchange dot com every 6 seconds. It appears the curl command called from the json-status script isn't honouring DNS TTLs properly.

Installed nscd on the feeder and it's stopped those lookups.

Might be worth checking your own machines if you've added the stats package.

 

It's more a linux sub-system that it doesn't cache DNS.

I'll look to add it to 1.29

 

That'd be great, thanks James!

 

It is for pihole users ;-)
We pay close attention to our stats including blocked sites and busy clients and my ADSBx Pi was the top DNS client before adding nscd.

I'm looking to add other ADSBx boxes at other sites so want them to behave (they'll be guests on other peoples' networks).

 

I really wish Pihole wouldn't make people experts on DNS.

https://netbeez.net/blog/how-dns-cache-works/

Some moron on reddit has a Pihole and thinks he's the haxxor preventing Internet Wizard.

https://www.reddit.com/r/ADSB/comments/cxz2cd/i_dont_trust_adsb_exchange_i_dont_think_you/


"It appears the curl command called from the json-status script isn't honouring DNS TTLs properly."

You're wong. It has nothing to do with curl.


Linux doesn't cache DNS at OS level, so I not sure I'll add another complexity layer to the image. Individuals can do this themselves and if it break their shit - not my problem to support all the Pi holes of the worlds. And there are a lot of Pi hole DNS Wizards ...

I suppose you could just add our static public IP as entries in hosts

http://manpages.ubuntu.com/manpages/trusty/man5/hosts.5.html

Code:

167.114.60.74  feed.adsbexchange.com
167.114.60.76  adsbexchange.com
167.114.60.77  adsbexchange.com

Or install and configure yourself.

Code:

sudo apt update
sudo apt install nscd

 

Thanks James. I'd previously installed nscd which slowed the requests - they now seem to query DNS only on TTL expiry.
So yes, that should work for others too.

 

Excellent.