apt-get errors building Ubuntu based Docker images from old images

Turns out if you have an older base image downloaded locally and you try to rebuild your own image based on it a couple of years later, you could get errors running apt-get in your own Dockerfiles. I just got errors like this rebuilding an image that I first created 2 years ago:

Err http://archive.ubuntu.com/ubuntu/ trusty-updates/main libcurl3 amd64 7.35.0-1ubuntu2.14
404  Not Found [IP: 91.189.88.149 80]
Get:16 http://archive.ubuntu.com/ubuntu/ trusty-updates/main ca-certificates all 20170717~14.04.1 [167 kB]
Err http://archive.ubuntu.com/ubuntu/ trusty-updates/main krb5-locales all 1.12+dfsg-2ubuntu5.3
404  Not Found [IP: 91.189.88.149 80]
Get:17 http://archive.ubuntu.com/ubuntu/ trusty/main libsasl2-modules amd64 2.1.25.dfsg1-17build1 [64.3 kB]
Err http://security.ubuntu.com/ubuntu/ trusty-security/main libcurl3 amd64 7.35.0-1ubuntu2.14
  404  Not Found [IP: 91.189.88.31 80]
Err http://security.ubuntu.com/ubuntu/ trusty-security/main openssl amd64 1.0.1f-1ubuntu2.23
  404  Not Found [IP: 91.189.88.31 80]
Err http://security.ubuntu.com/ubuntu/ trusty-security/main curl amd64 7.35.0-1ubuntu2.14
  404  Not Found [IP: 91.189.88.31 80]
Fetched 1375 kB in 7s (175 kB/s)
E: Failed to fetch http://archive.ubuntu.com/ubuntu/pool/main/k/krb5/libkrb5support0_1.12+dfsg-2ubuntu5.3_amd64.deb  404  Not Found [IP: 91.189.88.149 80]

If you delete the base ubuntu image you have cached locally, and try again, you’ll pull down a latest image, and now your build should continue as expected.

Next steps: From NGINX WordPress and MySQL running on Docker, to Kubernetes

This website running this blog has been running in Docker containers on a small-ish 4GB VPS for the past 9 months pretty much issue free. You can follow by journey to migrate this site to Docker in posts here and here.

Since I’ve been spending time recently getting up to speed with Kubernetes, the next logic step would be to deploy to a Kubernetes cluster, which would give me an opportunity to find out what it takes to run Kubernetes. I’ve looked at managed offerings on Google and AWS, but the cost for a few small personal projects is a little more than I want to spend.

I have a 8GB VPS ready to go, so far installed with Docker and Kubernetes running as a single node cluster, and I’m starting to plan my strategy for migrating to this new server. The first thing I’ve been thinking about is whether I should take my existing Docker images and just deploy to Kubernetes as is. Where I’ve got stuck so far is I don’t know enough about how to run NGINX with WordPress and MySQL in multiple pods, so I think I might install the WordPress Chart using Helm and for the time being not worry about how to do this myself.

The next thing I’ve been looking at is how to configure an Ingress to access different deployed services via different urls. I’ve been looking at setting up Traefik as the Ingress Controller to do this, and will be sharing a post about that config shortly. What I’m interested in is being able to deploy a number of different projects, including my WordPress site, and have them accessed via different urls, and it looks like Traefik will handle this fine.

I plan on writing some further posts as I make this transition over the next couple of weeks.

Running GitLab in a Docker container on a different port

Gitlab by default runs on port 80. GitLab in a Docker container runs the same as a when natively installed, but to change the port you need to change the config, and change the exposed ports on the container.

First, per steps here, start the container with:

docker run --detach \	
--hostname gitlab.example.com \
--publish host-https-port:container-https-port
--publish host-http-port:container-http-port
--publish 22:22 \
--name gitlab \
--restart always \
--volume /srv/gitlab/config:/etc/gitlab \
--volume /srv/gitlab/logs:/var/log/gitlab \
--volume /srv/gitlab/data:/var/opt/gitlab \
gitlab/gitlab-ce:latest

By default host-http-port and container-http-port are 80, and host-https-port container-https-port are 443. Change these to be whatever port you want to run on, but keep each pair the same (e.g. host-http-port and container-http-port = 8090)

When the container is up, start a shell into the running container:

docker exec -it containerid sh

and then edit the config file:

vi /etc/gitlab/gitlab.rb

and add line (at the top is ok):

external_url 'http://localhost:your-new-port-here

setting your-new-port-here to the new port.

Reconfigure the server:

gitlab-ctl reconfigure
gitlab-ctl restart

Done!

Updating rke created Kubernetes cluster from 1.11.3 to 1.11.5

There was a vulnerability found today in some older Kubernetes versions. There are already patched versions available. If you have 1.11.3 installed from rke, you can update to 1.11.5 by editing your cluster.yml, replacing the kubernetes image:

kubernetes: rancher/hyperkube:v1.11.3-rancher1

with

kubernetes: rancher/hyperkube:v1.11.5-rancher1

And then run ‘rke up’ again.

This is from this Github ticket.