Category Archives: Linux

Suricata and fail2ban

Posted on March 23, 2023 by blogger

In case you want to ban IP addresses based on Suricata fast.log, here is the filter you need: In the jail configuration, I suggest you change the default blocktype from REJECT to DROP. Edit 2023-03-24: you may want to use … Continue reading →

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Traefik & Grafana: auto-login based on source IP

Posted on October 19, 2022 by blogger

If you want to automatically (or force a specific) login requests to Grafana coming from a given source IP with Traefik, you can do it with a separate router and a middleware. This requires basic authentication to be enabled on … Continue reading →

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CentOS 8 End of Life: upgrade to CentOS Stream

Posted on February 15, 2022 by blogger

CentOS 8 End of Life has been effective since January 31 2021, official mirrors do not provide any packages anymore. Here is how to upgrade to latest release of CentOS 8 and switch to Stream. As always, prior to any … Continue reading →

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Elasticsearch in Docker: threat intelligence with filebeat

Posted on January 23, 2022 by blogger

Goals: collect observables from supported feeds collect observables from unsupported feeds with elastic-tip

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Elasticsearch in Docker: quick notes

Posted on January 23, 2022 by blogger

Goals: single node elasticsearch single node kibana password for all accounts https between all components behind traefik future post: collect network logs (routers) future post: collect application logs (web servers, dns servers, docker) future post: collect application metrics future post: … Continue reading →

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Traefik reverse-proxy with ModSecurity

Posted on January 22, 2022 by blogger

Traefik itself does not include WAF capabilities. If you want to add this capability, you can opt to replace Traefik with Apache httpd or nginx coupled with ModSecurity, however you loose the autoconfiguration of Traefik. Fortunately, Alexis Couvreur has developed … Continue reading →

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Backup gitea container

Posted on January 15, 2022 by blogger

Gitea is great when you want a fast, light and yet user-friendly git repositories. Alternatives would be Gogs, Gitlab or even Github. Gitea documentation tells you to use docker exec to perform a backup. However, this prevents you from using … Continue reading →

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A Raspberry Pi, a UPS and a couple of ESXi servers walk into a bar

Posted on December 16, 2021 by blogger

If you have the power of multiple servers connected to a UPS, you probably need to shut them down when the power goes down and before the UPS runs out of juice. Unless your UPS can be connected to the … Continue reading →

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Running a PKI using Smallstep certificates with Docker

Posted on September 12, 2021 by blogger

Recently, I had to set up a new PKI. I was going to go with the good old OpenSSL but it’s 2021, there must be a more userfriendly and, more importantly, automated approach. There are many open-source possibilities: EJBCA, cfssl, … Continue reading →

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Deprecation of apt-key in Debian-based distributions

Posted on August 7, 2021 by blogger

I recently installed an Ubuntu 21.04 and when I wanted to install Atom editor, I was given the following warning about apt-key being deprecated: After a bit of Googling around, I stumbled on this post on askubuntu.com explaining why apt-key … Continue reading →

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