DNS and maybe network issue in docker container

@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