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By default, Docker manipulates iptables rules to provide network isolation: Chain FORWARD (policy DROP) target prot opt source destination DOCKER all — 0.0.0.0/0 0.0.0.0/0 […] Chain DOCKER (1 references) target prot opt source destination I don’t mind having my iptables rules for forwarding manipulated, but there is a caveat: when you expose a container (with …
Continue reading “Preventing Docker from manipulating iptables rules”
I am using passwordless login via SSH on every box that I administer. Of course, my private SSH key is protected with a password that must be provided when accessing the key. Modern operating systems incorporate the usage of ssh-agent to “link” the user account to the SSH key(s), in order to unlock the SSH …
Continue reading “Automatically add SSH keys to SSH agent with GNOME and macOS”
Scenario: you are using a remote host as a virtualization host with libvirt and you want to manage it via ”Virtual machine manager” (virt-manager) over SSH. But SSH is listening on a non-standard port, and virt-manager does not offer you to connect to a remote libvirt instance on a non-standard port. Fear not, the option …
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I have a huge collection of bookmarks I collected over the years and I always have had the need to sync my bookmarks between my browsers of choice; Xmarks has always been one of the browser extensions I used for this need. Unfortunately, Xmarks is shutting down on May 1, 2018. I looked for some alternatives, like: …
Continue reading “Replacing Xmarks cross-browser sync service with Eversync”
I’m an avid user of Docker containers, using base images pulled from the public registry DockedHub. As you may know, Docker containers are based on Docked base images, e.g. I run postgres containers that are based on Postgres base image. It occurs that base images could get updated by their respective author (in our case Postgres team) and pushed to DockerHub. …
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Recentemente ho acquistato un iPhone 8 sul sito PuntoCom Shop (linkato in nofollow). Dopo una settimana dall’acquisto, il telefono ha presentato un difetto con la fotocamera, scattando foto con un alone rosa; il difetto è conosciuto da Apple, tant’è che non sono l’unico ad essere stato vittima di questo difetto hardware Apple. Recandomi in un …
Continue reading “Incubo PuntoCom Shop: NON acquistate su questo sito!”
During my usual backup routine, I wanted to gather how a Docker container I started a while ago was run, especially the docker run command; this is required in case I need to re-run that container and I want to preserve the options (e.g. env variables, ports, etc.). Let’s make an example. I run a …
Continue reading “Reverse engineer a Docker run command from an existing container”
I recently encountered a limitation during an experiment I was conducting; after some trial and error, I recognized that the limitation was due to cgroups. But let’s start from the beginning. I open sourced docker-salt, a small pet project I had in mind in order to have a full blown setup for SaltStack: a master …
The problem: SSH can be brute-forced I usually leave an SSH server on a dedicated port on every server I administer and, as you may recall, I even linked two well-written guides to properly configure and harden SSH services. Now, Internet is a notoriously bad place: scanners and exploiters have always been there, but brute-forcers …
Continue reading “Secure your SSH server against brute-force attacks with Fail2ban”
Motivation I switched my distribution of choice to OpenSUSE. There are a lot of motivations behind this choice: I wanted an enterprise-grade quality of software in terms of stability, package choice, and supportability Growing interest in software non-distribution specific and/or customized, e.g. Gnome Dogfooding After nearly one year of usage, I can say that I …
Continue reading “OpenSUSE Leap 42.2: this is how I work (my setup)”