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DNS and maybe network issue in docker container

Hi !
I had initially the problem with docker-compose, unable to reach a debian update site
Then I was able to build the image with --network host.
Let’s try with a simple container : busybox

Here are the commands tested

docker run busybox nslookup google.com
;; connection timed out; no servers could be reached

docker run busybox ping (the same)
ping: bad address ‘google.com

docker run busybox ping 216.58.213.174
^CPING 216.58.213.174 (216.58.213.174): 56 data bytes
— 216.58.213.174 ping statistics —
51 packets transmitted, 0 packets received, 100% packet loss

docker run --network host busybox ping (the same)
PING (the same) (216.58.213.174): 56 data bytes
64 bytes from 216.58.213.174: seq=0 ttl=54 time=4.205 ms
64 bytes from 216.58.213.174: seq=1 ttl=54 time=4.319 ms
64 bytes from 216.58.213.174: seq=2 ttl=54 time=4.322 ms
^C
— (the same) ping statistics —
3 packets transmitted, 3 packets received, 0% packet loss
round-trip min/avg/max = 4.205/4.282/4.322 ms

Any idea, what is wrong with my setup ?

Debian GNU/Linux 10 (buster) 4.9.137-xxxx-std-ipv6-64

docker version
Client: Docker Engine - Community
Version:           19.03.2
API version:       1.40
Go version:        go1.12.8
Git commit:        6a30dfc
Built:             Thu Aug 29 05:29:29 2019
OS/Arch:           linux/amd64
Experimental:      false

Server: Docker Engine - Community
Engine:
 Version:          19.03.2
 API version:      1.40 (minimum version 1.12)
 Go version:       go1.12.8
 Git commit:       6a30dfc
 Built:            Thu Aug 29 05:28:05 2019
 OS/Arch:          linux/amd64
 Experimental:     false
containerd:
 Version:          1.2.6
 GitCommit:        894b81a4b802e4eb2a91d1ce216b8817763c29fb
runc:
 Version:          1.0.0-rc8
 GitCommit:        425e105d5a03fabd737a126ad93d62a9eeede87f
docker-init:
 Version:          0.18.0
 GitCommit:        fec3683

“When posting issues or feedback, make sure to remove any sensitive information and please provide the following:”

OS Version/build

Docker Engine Type/version

@iloreto sorry I forgot to paste that -> post updated

Similar post without any answer :

Following this :

This first test fails, so it might not be a DNS problem at first …

docker run busybox ping -c 1 192.203.230.10
PING 192.203.230.10 (192.203.230.10): 56 data bytes
— 192.203.230.10 ping statistics —
1 packets transmitted, 0 packets received, 100% packet loss

But this one works :

docker run --network host busybox ping -c 1 192.203.230.10
PING 192.203.230.10 (192.203.230.10): 56 data bytes
64 bytes from 192.203.230.10: seq=0 ttl=57 time=4.450 ms
— 192.203.230.10 ping statistics —
1 packets transmitted, 1 packets received, 0% packet loss
round-trip min/avg/max = 4.450/4.450/4.450 ms

By default the network is set to “bridge” so check the output of “docker network inspect bridge”. Compare it with the output on the host where this is not seen.