gcloud alpha compute backend-services update-backend - update an existing backend in a backend service
gcloud alpha compute backend-services update-backend BACKEND_SERVICE_NAME ([--instance-group=INSTANCE_GROUP : --instance-group-region=INSTANCE_GROUP_REGION | --instance-group-zone=INSTANCE_GROUP_ZONE] | [--network-endpoint-group=NETWORK_ENDPOINT_GROUP : --network-endpoint-group-zone=NETWORK_ENDPOINT_GROUP_ZONE]) [--balancing-mode=BALANCING_MODE] [--capacity-scaler=CAPACITY_SCALER] [--description=DESCRIPTION] [--failover] [--max-utilization=MAX_UTILIZATION] [--global | --region=REGION] [--max-connections=MAX_CONNECTIONS | --max-connections-per-endpoint=MAX_CONNECTIONS_PER_ENDPOINT | --max-connections-per-instance=MAX_CONNECTIONS_PER_INSTANCE | --max-rate=MAX_RATE | --max-rate-per-endpoint=MAX_RATE_PER_ENDPOINT | --max-rate-per-instance=MAX_RATE_PER_INSTANCE] [GCLOUD_WIDE_FLAG ...]
(ALPHA) gcloud alpha compute backend-services update-backend updates a backend that is part of a backend service. This is useful for changing the way a backend behaves. Example changes that can be made include changing the load balancing policy and draining a backend by setting its capacity scaler to zero.
Backends are instance groups or network endpoint groups. One of the --network-endpoint-group or --instance-group flags is required to identify the backend that you are modifying. You cannot change the instance group or network endpoint group associated with a backend, but you can remove a backend and add a new one with backend-services remove-backend and backend-services add-backend.
The gcloud compute backend-services edit command can also update a backend if the use of a text editor is desired.
For more information about the available settings, see https://cloud.google.com/load-balancing/docs/backend-service.
- BACKEND_SERVICE_NAME
Name of the backend service to operate on.
- Exactly one of these must be specified:
- Instance Group
- --instance-group=INSTANCE_GROUP
Name of the instance group to update in the backend service. For details on valid instance names, refer to the criteria documented under the field 'name' at: https://cloud.google.com/compute/docs/reference/rest/v1/instances
This flag argument must be specified if any of the other arguments in this group are specified.
- At most one of these can be specified:
- --instance-group-region=INSTANCE_GROUP_REGION
Region of the instance group to update in the backend service. If not specified, you might be prompted to select a region (interactive mode only).
To avoid prompting when this flag is omitted, you can set the compute/region property:
$ gcloud config set compute/region REGION
A list of regions can be fetched by running:
$ gcloud compute regions list
To unset the property, run:
$ gcloud config unset compute/region
Alternatively, the region can be stored in the environment variable CLOUDSDK_COMPUTE_REGION.
- --instance-group-zone=INSTANCE_GROUP_ZONE
Zone of the instance group to update in the backend service. 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.
- Network Endpoint Group
- --network-endpoint-group=NETWORK_ENDPOINT_GROUP
Name of the network endpoint group to update in the backend service.
This flag argument must be specified if any of the other arguments in this group are specified.
- --network-endpoint-group-zone=NETWORK_ENDPOINT_GROUP_ZONE
Zone of the network endpoint group to update in the backend service. 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.
- --balancing-mode=BALANCING_MODE
Defines how to measure whether a backend can handle additional traffic or is fully loaded. For more information, see https://cloud.google.com/load-balancing/docs/backend-service#balancing-mode. BALANCING_MODE must be one of:
- CONNECTION
Available if the backend service's load balancing scheme is either INTERNAL or EXTERNAL. Available if the backend service's protocol is one of SSL, TCP, or UDP.
Spreads load based on how many concurrent connections the backend can handle.
For backend services with --load-balancing-scheme EXTERNAL, you must specify exactly one of these additional parameters: --max-connections, --max-connections-per-instance, or --max-connections-per-endpoint.
For backend services where --load-balancing-scheme is INTERNAL, you must omit all of these parameters.
- RATE
Available if the backend service's load balancing scheme is INTERNAL_MANAGED, INTERNAL_SELF_MANAGED, or EXTERNAL. Available if the backend service's protocol is one of HTTP, HTTPS, or HTTP/2.
Spreads load based on how many HTTP requests per second (RPS) the backend can handle.
You must specify exactly one of these additional parameters: --max-rate, --max-rate-per-instance, or --max-rate-per-endpoint.
- UTILIZATION
Available if the backend service's load balancing scheme is INTERNAL_MANAGED, INTERNAL_SELF_MANAGED, or EXTERNAL. Available only for managed or unmanaged instance group backends.
Spreads load based on the backend utilization of instances in a backend instance group.
The following additional parameters may be specified: --max-utilization, --max-rate, --max-rate-per-instance, --max-connections, --max-connections-per-instance. For valid combinations, see --max-utilization.
- --capacity-scaler=CAPACITY_SCALER
Scales down the target capacity (max utilization, max rate, or max connections) without changing the target capacity. For usage guidelines and examples, see Capacity scaler https://cloud.google.com/load-balancing/docs/backend-service#capacity_scaler.
- --description=DESCRIPTION
An optional, textual description for the backend.
- --failover
Designates whether this is a failover backend. More than one failover backend can be configured for a given BackendService. Not compatible with the --global flag
- --max-utilization=MAX_UTILIZATION
Defines the maximum target for average utilization of the backend instance group. Supported values are 0.0 (0%) through 1.0 (100%). This is an optional parameter for the UTILIZATION balancing mode.
You can use this parameter with other parameters for defining target capacity. For usage guidelines, see Balancing mode combinations https://cloud.google.com/load-balancing/docs/backend-service#balancing-mode-combos.
- At most one of these can be specified:
- --global
If set, the backend service is global.
- --region=REGION
Region of the backend service to operate on. Overrides the default compute/region property value for this command invocation.
- At most one of these can be specified:
- --max-connections=MAX_CONNECTIONS
Maximum concurrent connections that the backend can handle. Valid for network endpoint group and instance group backends (except for regional managed instance groups).
- --max-connections-per-endpoint=MAX_CONNECTIONS_PER_ENDPOINT
Only valid for network endpoint group backends. Defines a maximum number of connections per endpoint if all endpoints are healthy. When one or more endpoints are unhealthy, an effective maximum average number of connections per healthy endpoint is calculated by multiplying MAX_CONNECTIONS_PER_ENDPOINT by the number of endpoints in the network endpoint group, and then dividing by the number of healthy endpoints.
- --max-connections-per-instance=MAX_CONNECTIONS_PER_INSTANCE
Only valid for instance group backends. Defines a maximum number of concurrent connections per instance if all instances in the instance group are healthy. When one or more instances are unhealthy, an effective average maximum number of connections per healthy instance is calculated by multiplying MAX_CONNECTIONS_PER_INSTANCE by the number of instances in the instance group, and then dividing by the number of healthy instances.
- --max-rate=MAX_RATE
Maximum number of HTTP requests per second (RPS) that the backend can handle. Valid for network endpoint group and instance group backends (except for regional managed instance groups). Must not be defined if the backend is a managed instance group using load balancing-based autoscaling.
- --max-rate-per-endpoint=MAX_RATE_PER_ENDPOINT
Only valid for network endpoint group backends. Defines a maximum number of HTTP requests per second (RPS) per endpoint if all endpoints are healthy. When one or more endpoints are unhealthy, an effective maximum rate per healthy endpoint is calculated by multiplying MAX_RATE_PER_ENDPOINT by the number of endpoints in the network endpoint group, and then dividing by the number of healthy endpoints.
- --max-rate-per-instance=MAX_RATE_PER_INSTANCE
Only valid for instance group backends. Defines a maximum number of HTTP requests per second (RPS) per instance if all instances in the instance group are healthy. When one or more instances are unhealthy, an effective maximum RPS per healthy instance is calculated by multiplying MAX_RATE_PER_INSTANCE by the number of instances in the instance group, and then dividing by the number of healthy instances. This parameter is compatible with managed instance group backends that use autoscaling based on load balancing.
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.
This command is currently in alpha and might change without notice. If this command fails with API permission errors despite specifying the correct project, you might be trying to access an API with an invitation-only early access allowlist. These variants are also available:
$ gcloud compute backend-services update-backend
$ gcloud beta compute backend-services update-backend