Profile Ansible playbooks
Install profiling module:
ansible-galaxy collection install ansible.posix
Enable profiling in ansible.cfg in [defaults] section:
callback_whitelist = ansible.posix.profile_tasks
linux/
Unable to start Podman containers in LXD
[root@fe ~]# podman run hello-world
ERRO[0000] 'overlay' is not supported over extfs at "/var/lib/containers/storage/overlay"
Error: kernel does not support overlay fs: 'overlay' is not supported over extfs at "/var/lib/containers/storage/overlay": backing file system is unsupported for this graph driver
To fix this error, you’ll need to edit /etc/containers/storage.conf file and make sure that it contains the following options:
[storage]
driver = "overlay"
[storage.options]
mount_program = "/usr/bin/fuse-overlayfs"
Run the following command to verify the result:
podman --log-level=debug ps -a
How to check which cipher suites are supported by a website
sudo dnf install sslscan
sslscan example.com
Ansible: List all vars of the host
ansible stag-s4 -m debug -a "var=hostvars[inventory_hostname]"
Change DNS nameservers using NetworkManager
sudo nmcli connection modify <connection name> ipv4.dns "1.1.1.1 8.8.8.8"
Apply changes:
sudo nmcli dev reapply <interface>
How to reload the connection with NetworkManager
Reload interface configuration:
sudo nmcli connection reload
This command will ONLY make NetworkManager aware of new configuration changes. To apply the new changes, run the following command:
sudo nmcli dev reapply <interface>
Wait until DNS propagates
until [[ -n $(dig new.mydomain.com A +short @1.1.1.1) ]]; do echo "waiting..." && sleep 5; done
-n flag stands for non-empty string
Install module (collection) in Ansible
ansible-galaxy collection install containers.podman
Log Varnish hash data
When starting Varnish, add -p vsl_mask=+Hash argument to the command. Print
varnish logs with this command:
sudo varnishlog -n /opt/varnish -q 'ReqURL ~ "my_request"'