Cristian Livadaru's Blog

My personal view on things

Postfix complains about Cannot start TLS: handshake failure

Ok, this was a huge waste of time going down this rabbit hole. Postfix complains about handshake failure when trying to send emails over TLS. Non TLS works fine, receiving mails via TLS works fine, what gives?

Backing up databases to Minio S3 with Docker

You have lots of databases and you want to back them up to a central location. You could use a cloud provider, but what if you want to keep the data on your own server? Minio S3 is a great solution for this and with Docker it’s easy to set up.

Generating let's encrypt wildcard SSL certificates with INWX and DNS challenge

Using INWX as a DNS provider for the DNS challenge with nginx-proxy-manager and Let’s Encrypt wildcard SSL certificates is easy, but what the hell is that shared secret?

Generating let's encrypt wildcard SSL certificates with ISPConfig and DNS challenge

Generating wildcard SSL certificates with Let’s Encrypt and DNS challenge is a bit tricky with ISPConfig. It could be very straight forward but there is a little bug in the ISPConfig API or the nginx-proxy-manager that calls the API. Here is how you can work around it.

Happiness is temporary; all scenarios lead to loss

If you could be really happy but knew from the start it would end in sadness, would you choose that happiness or would you avoid it?

Fixing GitLab CI: dial tcp: lookup docker no such host

Another issue I keep encountering with project upgrades, which I tend to forget about, is that during the build phase on GitLab CI, the old dind (Docker in Docker) setup no longer works, resulting in a ’no such host’ error message.

Conferences with childcare

Childcare at conferences is something that I see way to little of but should be done much more often. While kids have fun and learn new things, parents can do the same. We are wasting future talent by not offering parents and children chances to learn new things.

💥Solving max_grant_frames under XEN

Being hit with this problem a second time, I noticed that the initial fix was not enough. There are pieces of informations scattered around several mailinglists, forum posts, blogs and also a very detailed technical explenation on what is happening under the hood, but I couldn’t find a post describing the solution. So here goes my take on how to solve this.

📣 Sensu Notifications

Notifications in sensu can be complicated, but sometimes you just need to think out of the box. Maybe there are better ways to distribute the notifications. Just send them to some central place where you have more control on distributing the notifications. While you could do this in sensu, it definitely is a pain in the ass to constantly run ansible to deploy the changes.

Wish you were here

A wonderful book, a story of someone leaving on a life-changing trip caused by the lockdown. Leaving for a short break, accepting the unknown caused by the lockdown, and getting your life turned upside down, all plans vanished in thin air. Realizing, that everything you planned is all a sham and you were just living that plan but living your life.