Today I learnt

Today I learned the order Ansible follows to get variable values. Command line option -e vars_files: vars: host_vars/ group_vars/ Role specific vars (role/default/main.yml) … Source

Today I learned that when performing SSH key authentication with OpenSSH. The client will look for the default key names id_rsa or id_dsa. If you want to use a custom name you should specify it in the command line via the -i option or reference it in the config file ssh_config. More

Today I learned that swarn node does not support specifying the pid namespace unlike docker-compose. Docker does not support a lot of other option in swarm mode. The whole list here

Today I learned, how Gluster Prometheus Exporter determine the leader node (peer). It simply compares the peers UUIDs alphabetically and elect the peer with the highest UUID as the cluster leader. We should note that healing and profile metrics can only be scraped from the leader node. Source

Today I learned how to update docker configs on stack deploy. Docker configs are immutable meaning when re-deploying a stack they can not be updated. The way to update configs on re-deploys is to create a new one each time a docker stack deploy is triggered. And a good way to to that is to template the config name using a unique value like (current system time). configs: settings.yml: name: settings-${SETTINGS_TIMESTAMP}....

Podman and Skopeo default to https for image pull and push. We can change this behaviour for specific registries. # /etc/containers/registries.conf (root) # ~/.config/containers/registries.conf (user) [registries.insecure] registries = ['localhost:5000'] More here

Today I learned how to synchronize multiple Tmux panes. So useful when in need of multi-machine/cluster setups. <Leader> : setw synchronize-panes on More