Shaaf's blog

A technical blog about Java, Kubernetes and things that matter

Setup docker on Fedora 33

I use Fedora as my regular Linux. And I have been doing that for years now, even though I am a developer its simple and straight forward enough to get my way around. It has some great features and spins. You should check it out at Fedora project

Here is a quick list of things that worked for me to setup docker on Fedora 33. I followed the guidelines here. Plus some more to config the firewall and user access.


Creating and deploying a Java 8 runtime container image

Orignally posted at Red Hat Developers

A Java runtime environment should be able to run compiled source code, whereas a development kit, for example, OpenJDK, would include all the libraries/binaries to compile and run the source code. Essentially the latter is a superset of the runtime environment. More details on OpenJDK support and lifecycle can be found here.

Red Hat ships and supports container images with OpenJDK for both Java 8 and 11. More details are here. If you are using Red Hat Middleware, the s2i images shipped are also useful to deploy, for example, on Red Hat Openshift Container Platform.


Install log; fedora 23, Virtualbox and windows 10

I have been using Linux for quite some time now, and jumping from windows xp to windows 10 was a huge change for me. Not just that I had completely forgotten what windows was all about, configs, screens, services. Anyways, I made a quick compilation of how you could run Fedora 23 and on VirtualBox running on windows 10.

Software versions

  • Windows: 10
  • VirtualBox: 5.0.16.x
  • Fedora: 23

Sidetrack tip: Even though the installer was in English , it changed my language to Danish. To change it goto indstillinger/sprog and change the options to English. that worked.


Howto setup ssh with selinux and firewalld

While running fedora, if you want to change the port for your ssh, just changing the firewall rules will not make a difference. If you are running selinux its important that you change the policy to allow a different port as well. I did learn it the hard way though, hopefully the following guide should be helpful.

Lets start by an introduction to semanage.

From man

Description

semanage is used to configure certain elements of SELinux policy without requiring modification to or recompilation from policy sources. This includes the mapping from Linux usernames to SELinux user identities (which controls the initial security context assigned to Linux users when they login and bounds their authorized role set) as well as security context mappings for various kinds of objects, such as network ports, interfaces, and nodes (hosts) as well as the file context mapping. See the EXAMPLES section below for some examples of common usage. Note that the semanage login command deals with the mapping from Linux usernames (logins) to SELinux user identities, while the semanage user command deals with the mapping from SELinux user identities to authorized role sets. In most cases, only the former mapping needs to be adjusted by the administrator; the latter is principally defined by the base policy and usually does not require modification.


FedUp and Fedora 18

Just now I made the update from Fedora 17 to 18. I didnt know that fedora 18 has a new update util called fedUp. If you are interested you could read here: https://fedoraproject.org/wiki/FedUp

Just do the following

yum --enablerepo=updates-testing install fedup

And then

fedup --network 18

It should ask for a reboot after some downloads, and that should just do the trick. atleast it did for me.