Can I get ip address inside my docker container?

Question

How to get container ip address inside this container?

\'docker inspect $hostname ...\' not suitable, because I don\'t share /var/run/docker.sock host file to contai

Answer 1

FROM alpine

# Upgrade grep so that it supports -Po flags
RUN apk add --no-cache --upgrade grep

ENV IPADDRESS "ip a show eth0 | grep -Po 'inet \K[\d.]+'"

Answer 2

I found solution to my problem:

/sbin/ip route|awk '/scope/ { print $9 }'

It's print something like: '172.17.0.135'

Answer 3

Why not something as simple as:

grep "`hostname`" /etc/hosts|awk '{print $1}'

or

grep "$HOSTNAME" /etc/hosts|awk '{print $1}'

Answer 4

This may work on some containers if it has the "hostname" command.

docker ps to get the (container id)

docker exec -it (container id) hostname -i

Answer 5

I can find the IP address with

hostname -i

Of course, that may not be completely accurate if there is more than one interface.

Edit

Note: According to the hostname man page, hostname -i uses DNS to resolve the ip address, where hostname -I displays all the addresses except loopback, does not depend on DNS, and is recommended.

In all my Docker containers, -i and -I return the same results (but this is not the case on my desktop).

Answer 6

You could also look for a line in /etc/hosts that ends with a container id and print the first field:

sed -n 's/^\([0-9\.]*\)[[:blank:]]*[0-9a-f]\{12,\}$/\1/p' /etc/hosts

I'd use awk, but standard awk in dedian:jessie doesn't support regex quantifiers like {12,}.