Reinstall package and recreate files
apt-get -o Dpkg::Options::="--force-confmiss" install --reinstall PACKAGE_NAME

ansible-playbook --limit '!hoost1:!host2' yourPlaybook.yml

Move shards from one node to another
curl -XPOST 'http://localhost:9200/_cluster/reroute' -d '{"commands" : [{"move" :{"index" : "indexname", "shard" : 1,"from_node" : "nodename", "to_node" : "nodename"}}]}'

Get docker ip addresses
docker inspect -f '{{.Name}} - {{range .NetworkSettings.Networks}}{{.IPAddress}}{{end}}' $(docker ps -aq)

In order to download only package via apt, with a particular version

apt-get install --download-only metricbeat=7.6.1

.deb package you'll find at
ls -l /var/cache/apt/archives

Show cert names
certbot certificates

Delete standalone certificate with:
certbot delete --cert-name CERT_NAME

In order to clean up journalctl logs use

Set time retention
journalctl --vacuum-time=2d

Set size retention
journalctl --vacuum-size=500M

Set rate limmiting

in nginx.conf http block set:
limit_req_zone $binary_remote_addr zone=mylimit:10m rate=10r/s;

Show docker swarm nodes labels
docker node ls -q | xargs docker node inspect -f '{{ .ID }} [{{ .Description.Hostname }}]: {{ .Spec.Labels }}'

Check node id
docker node ls