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gcloud compute instance-groups unmanaged add-instances

NAME
gcloud compute instance-groups unmanaged add-instances - adds instances to an unmanaged instance group by name
SYNOPSIS
gcloud compute instance-groups unmanaged add-instances NAME --instances=INSTANCE,[INSTANCE,…] [--zone=ZONE] [GCLOUD_WIDE_FLAG …]
DESCRIPTION
gcloud compute instance-groups unmanaged add-instances adds existing instances to an unmanaged instance group by name. For example: 
gcloud compute instance-groups unmanaged add-instances my-group --instances my-instance-1,my-instance-2 --zone us-central1-a
POSITIONAL ARGUMENTS
NAME
Name of the instance group to operate on.
REQUIRED FLAGS
--instances=INSTANCE,[INSTANCE,…]
A list of names of instances to add to the instance group. These must exist beforehand and must live in the same zone as the instance group.
OPTIONAL FLAGS
--zone=ZONE
Zone of the instance group to operate on. If not specified and the compute/zone property isn't set, you might be prompted to select a zone (interactive mode only).

To avoid prompting when this flag is omitted, you can set the compute/zone property: 

gcloud config set compute/zone ZONE

A list of zones can be fetched by running: 

gcloud compute zones list

To unset the property, run: 

gcloud config unset compute/zone
 Alternatively, the zone can be stored in the environment variable CLOUDSDK_COMPUTE_ZONE.
GCLOUD WIDE FLAGS
These flags are available to all commands: --access-token-file, --account, --billing-project, --configuration, --flags-file, --flatten, --format, --help, --impersonate-service-account, --log-http, --project, --quiet, --trace-token, --user-output-enabled, --verbosity.

Run $ gcloud help for details.

NOTES
These variants are also available: 
gcloud alpha compute instance-groups unmanaged add-instances
 
gcloud beta compute instance-groups unmanaged add-instances
 
gcloud preview compute instance-groups unmanaged add-instances