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Failed to build docker image with warning message "IPv4 forwarding is disabled. Networking will not work"
Problem
Step 3/12 : RUN apk add openjdk11
---> [Warning] IPv4 forwarding is disabled. Networking will not work.
---> Running in 0f20ee3ab3eb
fetch https://dl-cdn.alpinelinux.org/alpine/v3.16/main/x86_64/APKINDEX.tar.gz
ERROR: https://dl-cdn.alpinelinux.org/alpine/v3.16/main: temporary error (try again later)
WARNING: Ignoring https://dl-cdn.alpinelinux.org/alpine/v3.16/main: No such file or directory
fetch https://dl-cdn.alpinelinux.org/alpine/v3.16/community/x86_64/APKINDEX.tar.gz
ERROR: https://dl-cdn.alpinelinux.org/alpine/v3.16/community: temporary error (try again later)
WARNING: Ignoring https://dl-cdn.alpinelinux.org/alpine/v3.16/community: No such file or directory
ERROR: unable to select packages:
openjdk11 (no such package):
required by: world[openjdk11]
The command '/bin/sh -c apk add openjdk11' returned a non-zero code: 1
Solution
Update configuration
sysctl -w net.ipv4.ip_forward=1
Read configuration
sysctl net.ipv4.ip_forward