You have already seen what the init command is for, that being to create the swarm cluster, add (this) the first Docker node to it, and then set up and enable all of the swarm features we just covered. The init command can be as simple as using it with no parameters, but there are many optional parameters available to fine-tune the initialization process. You can get a full list of the optional parameters, as usual, by using --help, but let's consider a few of the available parameters now:

• --autolock: Use this parameter to enable manager autolocking.
• --cert-expiry duration: Use this parameter to change the default validity period (of 90 days) for node certificates.
• --external-ca external-ca: Use this parameter to specify one or more certificate-signing endpoints, that is, external CAs.