# Detailed description of a few selected arguments

This list is not the full list, but a few arguments that where chosen.

## admin-access

`admin-access` controls the CIDR which can access the admin endpoints (SSH to each node, HTTPS to the master).

If not specified, no IP level restrictions will apply (though there are still restrictions, for example you need
a permitted SSH key to access the SSH service!).

Examples:

**CLI:**

`--admin-access=18.0.0.0/8` to restrict to IPs in the 18.0.0.0/8 CIDR

`--admin-access=18.0.0.0/8 --admin-access=19.0.0.0/8` to restrict to IPs in the 18.0.0.0/8 and 19.0.0.0/8 CIDR blocks

**YAML:**

See the docs in [cluster_spec.md#adminaccess](cluster_spec.md#adminaccess)

## dns-zone

`dns-zone` controls the Route53 hosted zone in which DNS records will be created.  It can either by the name
of the hosted zone (`example.com`), or it can be the ID of the hosted zone (`Z1GABCD1ABC2DEF`)

Suppose you are creating a cluster named "dev.kubernetes.example.com`:

* You can specify a `--dns-zone=example.com` (you can have subdomains in a hosted zone)
* You could also use `--dns-zone=kubernetes.example.com`

You do have to set up the DNS nameservers so your hosted zone resolves.  kops used to create the hosted
zone for you, but now (as you have to set up the nameservers anyway), there doesn't seem much reason to do so!

If you don't specify a dns-zone, kops will list all your hosted zones, and choose the longest that
is a suffix of your cluster name.  So for `dev.kubernetes.example.com`, if you have `kubernetes.example.com`,
`example.com` and `somethingelse.example.com`, it would choose `kubernetes.example.com`.  `example.com` matches
but is shorter; `somethingelse.example.com` is not a suffix-match.

Examples:

`--dns-zone=example.com` to use the hosted zone with a name of example.com

## cloud-labels

`cloud-labels` specifies tags for instance groups in AWS. The supported format is a CSV list of key=value pairs.
Keys and values must not contain embedded commas but they may contain equals signs ('=') as long as the field is
quoted:
* `--cloud-labels "Project=\"Name=Foo Customer=Acme\",Owner=Jane Doe"` will be parsed as {Project:"Name=Foo Customer=Acme",
Owner: "Jane Doe"}

## UpdatePolicy

Cluster.Spec.UpdatePolicy

Values:

* `external` updates are performed by an external system (or manually), should not be automatically applied

* unset means to use the default policy, which is currently to apply OS security updates unless they require a reboot

## out

`out` determines the directory into which Kops will write the target output for Terraform and CloudFormation.  It defaults to `out/terraform` and `out/cloudformation` respectively.

# API only Arguments

Certain arguments can only be passed via the API, eg, `kops edit cluster`. The following documents some of the more interesting or lesser-known options. See the [Cluster Spec](./cluster_spec.md) page for more fields.

## kubeletPreferredAddressTypes

The apiserver can now select which type of kubelet-reported address to use for apiserver->node communications, using the --kubelet-preferred-address-types flag. (https://github.com/kubernetes/kubernetes/pull/35497, @liggitt)

Example:

```
kubeAPIServer:
	kubeletPreferredAddressTypes:
	- InternalIP
	- ExternalIP
```

More information about using YAML is available [here](manifests_and_customizing_via_api.md).
