Passed the Red Hat RHCSA exam

Today I passed the Red Hat RHCSA exam with the maximum 300/300 100% score! 😁 I had a good feeling during the exam, and after about an hour I got the following email from Red Hat. The results of your recent EX200 Red Hat Certified System Administrator Exam are reported below. Passing score: 210 Your score: 300 Result: PASS Congratulations -- you have earned the Red Hat Certified System Administrator certification....

February 6, 2020 · Dennis Kruyt

SUSE SLES 15 Container in LXD

I am a big fan of LXD and lot of my ‘home infra’ and VPS’s are all running LXD container. Also I am using LXD at work to create test setup for al sorts of Linux OS’s and applications. Most “free” Linux OS’s are already in the LXD image repository. But sometime’s I need a non free Linux OS. Such as SUSE Linux Enterprise Server, or SLES for short. Off-course I can run this in a VPS just by installing it from an ISO....

January 20, 2020 · Dennis Kruyt

Ansible CICD pipeline with GitLab

In this post I will show how I use GitLab CICD with Ansible. I’ll show the pipelines and how the merge requests are handled for full control and auditing. GitLab flow The GitLab flow is as following, you have one or more dev/working branches. To push code to the staging environment you do this via an merge request in GitLab, en to get this code in to production. Again via a merge request from the master branch to the production branch....

January 17, 2020 · Dennis Kruyt

3d print project, lampshade

A couple of weeks ago I gave myself a 3d print for a present. 😝 I opted for a Creality Ender 3 pro and order it from Ali Express. With the first print I was amazed how good the quality now is on these budget printers. My last experience with 3d printing was about 10 years ago and the quality was quite different then on budget printers. So I am quite happy with this printer....

December 9, 2019 · Dennis Kruyt

Ghost blog caching with Varnish

In this post I show a few of my tip’s for using Varnish for caching and Ghost together. Don’t cache everything Caching is good, but we don’t want to cache everything in ghost, we don’t want to cache the admin and preview pages in ghost. Add the following in the sub vcl_recv part. # Did not cache the admin and preview pages if (req.url ~ "/(admin|p|ghost)/") { return (pass); } restart Varnish to activate the changes....

October 6, 2019 · Dennis Kruyt

ZeroTier on a Ubiquiti EdgeRouter (part 2)

In my previous post I showed how to install ZeroTier on the EdgeRouter, after installing we need to rename the ZeroTier interface to ethx interface to show up in EdgeOS. ZeroTier on a Ubiquiti EdgeRouter With the new EdgeOS version 2 firmware for the EdgeRouter it is now possible to install ZeroTier on this router. Dennis Kruyt Kruyt.org Now I adopted EdgeOS (which is basically VyOS/Vyatta running on the EdgeRouter) to support ZeroTier from the native CLI with tab completion....

September 27, 2019 · Dennis Kruyt

MySQL tuning

At my work in the past I needed to trouble shoot and tune MySQL installations. Here are some best practises I have used.

September 24, 2019 · Dennis Kruyt

Linux disk performance tuning

Some option in Linux that can be used for disk related performance tuning.

September 22, 2019 · Dennis Kruyt

Instagram/Facebook HELO/SPF fail

I’ve been trying to receive an email from Instagram, but it wasn’t coming through. Upon inspecting my mail logs, I encountered the following log message: Sep 13 03:50:51 mailserver postfix/smtpd[28105]: NOQUEUE: reject: RCPT from 66-220-155-156.mail-mail.facebook.com[66.220.155.156]: 550 5.7.1 <[email protected]>: Recipient address rejected: Message rejected due to: domain owner discourages use of this host. Please see http://www.openspf.net/Why?s=helo;id=mx-out.facebook.com;ip=66.220.155.156;[email protected]; from=<[email protected]> to=<[email protected]> proto=ESMTP helo=<mx-out.facebook.com> This indicates that the email failed due to SPF (Sender Policy Framework) checks....

September 13, 2019 · Dennis Kruyt

ZeroTier on a Ubiquiti EdgeRouter

With the new EdgeOS version 2 firmware for the EdgeRouter it is now possible to install ZeroTier on this router.

August 31, 2019 · Dennis Kruyt