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gcloud compute instance-groups managed resize

NAME
gcloud compute instance-groups managed resize - set managed instance group size
SYNOPSIS
gcloud compute instance-groups managed resize NAME --size=SIZE [--region=REGION     | --zone=ZONE] [GCLOUD_WIDE_FLAG …]
DESCRIPTION
gcloud compute instance-groups managed resize resize a managed instance group to a provided size.

If you resize down, the Instance Group Manager service deletes instances from the group until the group reaches the desired size. Instances are deleted in arbitrary order but the Instance Group Manager takes into account some considerations before it chooses which instance to delete. For more information, see https://cloud.google.com/compute/docs/reference/rest/v1/instanceGroupManagers/resize.

If you resize up, the service adds instances to the group using the current instance template until the group reaches the desired size.
POSITIONAL ARGUMENTS
NAME
Name of the managed instance group to operate on.
REQUIRED FLAGS
--size=SIZE
Target number of running instances in managed instance group.
OPTIONAL FLAGS
At most one of these can be specified:
--region=REGION
Region of the managed instance group to operate on. If not specified, you might be prompted to select a region (interactive mode only).

A list of regions can be fetched by running: 

gcloud compute regions list
 Overrides the default compute/region property value for this command invocation.
--zone=ZONE
Zone of the managed instance group to operate on. If not specified, you might be prompted to select a zone (interactive mode only).

A list of zones can be fetched by running: 

gcloud compute zones list
 Overrides the default compute/zone property value for this command invocation.
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 managed resize
 
gcloud beta compute instance-groups managed resize
 
gcloud preview compute instance-groups managed resize