X forwarding over ssh and sudo

This has bugged me for years – with random success depending on sudo, su – etc.

The proper solution:-

steve@studio:~$ ssh -X 192.168.0.201
Last login: Fri Feb 10 21:54:11 2017 from 192.168.0.247
[steve@fleabox ~]$ xauth list
fleabox.track3.org.uk/unix:12  MIT-MAGIC-COOKIE-1  b4339e07fb0e4febdde6128fc56419e4
[steve@fleabox ~]$ sudo su -
[sudo] password for steve: 
[root@fleabox ~]# xauth add fleabox.track3.org.uk/unix:12  MIT-MAGIC-COOKIE-1  b4339e07fb0e4febdde6128fc56419e4
[root@fleabox ~]# virt-manager &
[1] 7168

Success!

Docker and Apache QuickStart

mkdir -p dockerfile/C7httpd; cd dockerfile/C7httpd
vi Dockerfile

FROM centos:7
MAINTAINER "Steve Netting" steve@netting.org.uk
ENV container docker
RUN yum -y --setopt=tsflags=nodocs update && \
yum -y --setopt=tsflags=nodocs install httpd && \
yum clean all

EXPOSE 80

ADD run-httpd.sh /run-httpd.sh
RUN chmod -v +x /run-httpd.sh

CMD ["/run-httpd.sh"]

vi run-httpd.sh

#!/bin/bash

# Make sure we're not confused by old, incompletely-shutdown httpd
# context after restarting the container. httpd won't start correctly
# if it thinks it is already running.
rm -rf /run/httpd/* /tmp/httpd*

exec /usr/sbin/apachectl -DFOREGROUND

docker build .
docker images
docker run -d -p:8082:80 steve/httpd:latest
docker ps
curl http://localhost:8082

... If you can read this page it means that this site is working properly ...

To start interactive shell from inside running container:
docker exec -i -t romantic_noyce /bin/bash