Hi!
I’m running HA as docker image and since ever I noticed that certain devices, e.g. my UPS via nut integration does not deliver values during the night when I turn of my Internet connection. I traced it down to a DNS resolving issue which I do not understand.
To be on the safe side I installed dnsmasq and set my internal DNS server:
[16:17:59] INFO: Configuring dnsmasq...
[16:17:59] INFO: Starting dnsmasq...
dnsmasq[6]: started, version 2.80 cachesize 150
dnsmasq[6]: compile time options: IPv6 GNU-getopt no-DBus no-i18n no-IDN DHCP DHCPv6 no-Lua TFTP no-conntrack ipset auth no-DNSSEC loop-detect inotify dumpfile
dnsmasq[6]: using nameserver 192.168.110.1#53
dnsmasq[6]: cleared cache
When I log into the container everything is fine (kvm.lan is the host that runs upsd):
~ $ ping kvm.lan
PING kvm.lan (192.168.110.5): 56 data bytes
64 bytes from 192.168.110.5: seq=0 ttl=63 time=0.447 ms
64 bytes from 192.168.110.5: seq=1 ttl=63 time=0.370 ms
--- kvm.lan ping statistics ---
2 packets transmitted, 2 packets received, 0% packet loss
round-trip min/avg/max = 0.370/0.408/0.447 ms
~ $ dig kvm.lan
; <<>> DiG 9.14.12 <<>> kvm.lan
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 56123
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;kvm.lan. IN A
;; ANSWER SECTION:
kvm.lan. 5 IN A 192.168.110.5
;; Query time: 5 msec
;; SERVER: 127.0.0.11#53(127.0.0.11)
;; WHEN: Sun Jul 19 16:11:59 CEST 2020
;; MSG SIZE rcvd: 52
When I turn off the Internet connection it takes some time but then it gets strange. Ping stops working:
~ $ ping kvm.lan
ping: bad address 'kvm.lan'
The DNS of the container cannot resolve the address any more:
~ $ dig kvm.lan
; <<>> DiG 9.14.12 <<>> kvm.lan
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 52586
;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1
;; WARNING: recursion requested but not available
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
; COOKIE: d1426e27e7f4d858 (echoed)
;; QUESTION SECTION:
;kvm.lan. IN A
although my configured (internal) DNS does answer without issues:
~ $ dig kvm.lan @192.168.110.1
; <<>> DiG 9.14.12 <<>> kvm.lan @192.168.110.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 55099
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;kvm.lan. IN A
;; ANSWER SECTION:
kvm.lan. 0 IN A 192.168.110.5
;; Query time: 1 msec
;; SERVER: 192.168.110.1#53(192.168.110.1)
;; WHEN: Sun Jul 19 16:27:19 CEST 2020
;; MSG SIZE rcvd: 52
Does anyone have good ideas on that? Why does dnsmasq (of the container) not answer although I configured only one upstream DNS which obviously does answer? I had a look at other posts with similar issues but couldn’t find a solution and some are already quite old.
Here is my setup if that helps tracing down the issue:
| arch | x86_64 |
| chassis | vm |
| dev | false |
| docker | true |
| docker_version | 19.03.8 |
| hassio | true |
| host_os | Debian GNU/Linux 10 (buster) |
| installation_type | Home Assistant Supervised |
| os_name | Linux |
| os_version | 5.4.0-0.bpo.2-amd64 |
| python_version | 3.7.7 |
| supervisor | 229 |
| timezone | Europe/Vienna |
| version | 0.112.4 |
| virtualenv | false |
I have a few further issues when being offline (mainly GUI) but I would like to go one by one and continuously getting values from my sensors has highest priority.
Thanks a lot,
Patrick