difficulty with alpine update calls on linux with proxy

[tmills]

In trying to build any of the containers on my work desktop (xubuntu 16.06) I get errors in the docker build process when trying to update the packages. I know the servers are working because I can successfully download the files in question with wget manually. I tried setting proxy settings everywhere (linux, docker config files, docker build command line). Maybe there is a way to set them in the alpine container?

Sending build context to Docker daemon   2.79MB
Step 1/25 : FROM openjdk:8-alpine
 ---> 478bf389b75b
Step 2/25 : RUN apk update && apk add ca-certificates openssl wget unzip python git perl
 ---> Running in 1dad7ef9b453
fetch http://dl-cdn.alpinelinux.org/alpine/v3.6/main/x86_64/APKINDEX.tar.gz
ERROR: http://dl-cdn.alpinelinux.org/alpine/v3.6/main: No such file or directory
WARNING: Ignoring APKINDEX.84815163.tar.gz: No such file or directory
fetch http://dl-cdn.alpinelinux.org/alpine/v3.6/community/x86_64/APKINDEX.tar.gz
ERROR: http://dl-cdn.alpinelinux.org/alpine/v3.6/community: No such file or directory
WARNING: Ignoring APKINDEX.24d64ab1.tar.gz: No such file or directory
2 errors; 51 distinct packages available
The command '/bin/sh -c apk update && apk add ca-certificates openssl wget unzip python git perl' returned a non-zero code: 2

[MatthewVita]

Dang, it looks like we're doing the right thing with https://github.com/gliderlabs/docker-alpine/issues/207#issuecomment-241308729

Other threads on the www suggesting using a mirror, but it's strange that this server is up?

[MatthewVita]

Oh, actually this comment makes sense: https://github.com/gliderlabs/docker-alpine/issues/207#issuecomment-325156744

Perhaps it's a messed up container cache issue. Try this.

This would explain why things are working for me. If all else fails, you can also take the nuclear option to rebuild from a fresh canvas: https://github.com/MatthewVita/zshrc/blob/master/.zshrc#L81-L88

[tmills]

This workaround works: https://github.com/gliderlabs/docker-alpine/issues/191#issuecomment-314148406

but not sure how reliable it is to put urls with specific version numbers inside the docker file.