A few days ago I noticed that my pihole.logs are huge. We are two adults and a 12yo with a limited usage of 1 hour / day on his mobile.
The log was about 10MB / day.
The first thing I noted was that we got a huge number of requests from our fire tv stick.
I used to have like 2.500 requests but suddenly this rose to 10.000 requests / day. The same requests over and over again while we are all asleep and the stick should be idling.
About every two minutes especially to firetvcaptiveportal.com and cnd.optimizely.com. The thing is that a single one of those requests easily spans 20 lines, e.g.
Dec 18 00:11:06 dnsmasq[587]: query[AAAA] firetvcaptiveportal.com from 192.168.178.30
Dec 18 00:11:06 dnsmasq[587]: forwarded firetvcaptiveportal.com to 2001:1608:xx:xx::xxxx:xxxx
Dec 18 00:11:06 dnsmasq[587]: forwarded firetvcaptiveportal.com to 84.200.70.40
Dec 18 00:11:06 dnsmasq[587]: forwarded firetvcaptiveportal.com to 2620:119:35::35
Dec 18 00:11:06 dnsmasq[587]: forwarded firetvcaptiveportal.com to 208.67.222.222
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 2600:1f18:1805:8601:713b:508e:a786:40c9
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 2600:1f18:1805:8601:5848:6783:9bd8:44fa
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 2600:1f18:1805:8601:c6d0:b5b9:75f4:46f6
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 2600:1f18:1805:8604:d526:6df6:c2eb:6fe7
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 2600:1f18:1805:8607:6b66:a51c:1259:d4bf
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 2600:1f18:1805:8604:d45f:8661:c361:4e7a
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 2600:1f18:1805:8601:8248:14c:b359:beb3
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 2600:1f18:1805:8604:5ec7:f25a:d2b:8995
Dec 18 00:11:06 dnsmasq[587]: query[A] firetvcaptiveportal.com from 192.168.178.30
Dec 18 00:11:06 dnsmasq[587]: forwarded firetvcaptiveportal.com to 2001:1608:xx:xx::xxxx:xxxx
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 52.86.185.40
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 52.1.167.159
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 174.129.230.26
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 34.192.235.166
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 52.1.182.127
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 52.4.27.132
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 23.20.191.165
Dec 18 00:11:06 dnsmasq[587]: reply firetvcaptiveportal.com is 34.238.204.58
Now imagine 10.000 requests of that kind and you get the picture. Any ideas about the rise of numbers? What numbers should I expect for a fire tv stick?
Anyway I bypassed pihole for the fire tv stick and expected a much smaller log from now on.
To my surprise there are other spammers. Yesterday evening my missus watched the voice of Germany on her android tablet and between 20:22 and 23:58 I have 1849 of those lookups.
3 Times a second then about 20 secs break and then again and again...
Dec 20 22:27:01 dnsmasq[587]: query[A] e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com from 192.168.178.33
Dec 20 22:27:01 dnsmasq[587]: forwarded e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com to 2001:1608:xx:xx::xxxx:xxxx
Dec 20 22:27:01 dnsmasq[587]: reply e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com is <CNAME>
Dec 20 22:27:01 dnsmasq[587]: reply cws.conviva.com is blocked during CNAME inspection
Dec 20 22:27:01 dnsmasq[587]: query[A] e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com from fd00::xxxx:xxxx:xxxx:xxxx
Dec 20 22:27:01 dnsmasq[587]: forwarded e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com to 2001:1608:xx:xx::xxxx:xxxx
Dec 20 22:27:01 dnsmasq[587]: reply e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com is <CNAME>
Dec 20 22:27:01 dnsmasq[587]: reply cws.conviva.com is blocked during CNAME inspection
Dec 20 22:27:01 dnsmasq[587]: query[A] e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com from 192.168.178.33
Dec 20 22:27:01 dnsmasq[587]: forwarded e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com to 2001:1608:xx:xx::xxxx:xxxx
Dec 20 22:27:01 dnsmasq[587]: reply e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com is <CNAME>
Dec 20 22:27:01 dnsmasq[587]: reply cws.conviva.com is blocked during CNAME inspection
Dec 20 22:27:01 dnsmasq[587]: query[A] e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com from fd00::xxxx:xxxx:xxxx:xxxx
Dec 20 22:27:01 dnsmasq[587]: forwarded e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com to 2001:1608:xx:xx::xxxx:xxxx
Dec 20 22:27:01 dnsmasq[587]: reply e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com is <CNAME>
Dec 20 22:27:01 dnsmasq[587]: reply cws.conviva.com is blocked during CNAME inspection
Dec 20 22:27:01 dnsmasq[587]: query[A] e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com from 192.168.178.33
Dec 20 22:27:01 dnsmasq[587]: forwarded e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com to 2001:1608:xx:xx::xxxx:xxxx
Dec 20 22:27:01 dnsmasq[587]: reply e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com is <CNAME>
Dec 20 22:27:01 dnsmasq[587]: reply cws.conviva.com is blocked during CNAME inspection
Dec 20 22:27:01 dnsmasq[587]: query[A] e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com.fritz.box from fd00::xxxx:xxxx:xxxx:xxxx
Dec 20 22:27:01 dnsmasq[587]: forwarded e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com.fritz.box to 192.168.178.1
Dec 20 22:27:01 dnsmasq[587]: reply e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com.fritz.box is NXDOMAIN
Dec 20 22:27:01 dnsmasq[587]: query[A] e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com.fritz.box from 192.168.178.33
Dec 20 22:27:01 dnsmasq[587]: cached e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com.fritz.box is NXDOMAIN
Dec 20 22:27:01 dnsmasq[587]: query[A] e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com.fritz.box from fd00::xxxx:xxxx:xxxx:xxxx
Dec 20 22:27:01 dnsmasq[587]: cached e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com.fritz.box is NXDOMAIN
Dec 20 22:27:01 dnsmasq[587]: query[A] e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com.fritz.box from 192.168.178.33
Dec 20 22:27:01 dnsmasq[587]: cached e1cd4958785f7e0dcfaee56d57a7db4096b34051.cws.conviva.com.fritz.box is NXDOMAIN
My questions:
- Does anyone have reliable info about the DNS TTL on android devices? Why does the android tablet not keep the dns entries in its dns cache?
- Why do I see 3 requests within one second? Each time from the IPv4, the IPv6 and the link local address, so overall 9 requests / sec?
- Can dnsmasq be adjusted so that it does not log the cached queries and results? How?
- At the moment I have pihole as the local DNS-Server. If I set it as the upstream DNS server on the internet connection and use the internal Fritzbox DNS-Server as my local DNS-Server:
All that excessive logging should be gone, right? As the Fritzbox-DNS-Server would answer out of its cache and would not have to talk to the pihole dnsmasq. Correct? - What will I loose if I disable logging to my /var/log/pihole.log and will there anything be missing in my pihole-FTL.db? How to disable logging to only the /var/log/pihole.log and not to pihole-FTL.db?
Thx in advance