REST Resource: regionBackendServices

Resource: BackendService

Represents a Backend Service resource.

A backend service contains configuration values for Google Cloud Platform load balancing services.

Backend services in Google Compute Engine can be either regionally or globally scoped.

For more information, read Backend Services.

JSON representation 
{
  "id": string,
  "creationTimestamp": string,
  "name": string,
  "description": string,
  "selfLink": string,
  "backends": [
    {
      "description": string,
      "group": string,
      "balancingMode": enum,
      "maxUtilization": number,
      "maxRate": integer,
      "maxRatePerInstance": number,
      "maxRatePerEndpoint": number,
      "maxConnections": integer,
      "maxConnectionsPerInstance": integer,
      "maxConnectionsPerEndpoint": integer,
      "capacityScaler": number
    }
  ],
  "healthChecks": [
    string
  ],
  "timeoutSec": integer,
  "port": integer,
  "protocol": enum,
  "fingerprint": string,
  "portName": string,
  "enableCDN": boolean,
  "sessionAffinity": enum,
  "affinityCookieTtlSec": integer,
  "region": string,
  "loadBalancingScheme": enum,
  "connectionDraining": {
    "drainingTimeoutSec": integer
  },
  "iap": {
    "enabled": boolean,
    "oauth2ClientId": string,
    "oauth2ClientSecret": string,
    "oauth2ClientSecretSha256": string
  },
  "cdnPolicy": {
    "cacheKeyPolicy": {
      "includeProtocol": boolean,
      "includeHost": boolean,
      "includeQueryString": boolean,
      "queryStringWhitelist": [
        string
      ],
      "queryStringBlacklist": [
        string
      ]
    },
    "signedUrlKeyNames": [
      string
    ],
    "signedUrlCacheMaxAgeSec": string
  },
  "customRequestHeaders": [
    string
  ],
  "securityPolicy": string,
  "logConfig": {
    "enable": boolean,
    "sampleRate": number
  },
  "localityLbPolicy": enum,
  "consistentHash": {
    "httpCookie": {
      "name": string,
      "path": string,
      "ttl": {
        "seconds": string,
        "nanos": integer
      }
    },
    "httpHeaderName": string,
    "minimumRingSize": string
  },
  "circuitBreakers": {
    "maxRequestsPerConnection": integer,
    "maxConnections": integer,
    "maxPendingRequests": integer,
    "maxRequests": integer,
    "maxRetries": integer
  },
  "outlierDetection": {
    "consecutiveErrors": integer,
    "interval": {
      "seconds": string,
      "nanos": integer
    },
    "baseEjectionTime": {
      "seconds": string,
      "nanos": integer
    },
    "maxEjectionPercent": integer,
    "enforcingConsecutiveErrors": integer,
    "enforcingSuccessRate": integer,
    "successRateMinimumHosts": integer,
    "successRateRequestVolume": integer,
    "successRateStdevFactor": integer,
    "consecutiveGatewayFailure": integer,
    "enforcingConsecutiveGatewayFailure": integer
  },
  "network": string,
  "kind": string
}
Fields
id

string (fixed64 format)

[Output Only] The unique identifier for the resource. This identifier is defined by the server.
creationTimestamp

string

[Output Only] Creation timestamp in RFC3339 text format.
name

string

Name of the resource. Provided by the client when the resource is created. The name must be 1-63 characters long, and comply with RFC1035. Specifically, the name must be 1-63 characters long and match the regular expression [a-z]([-a-z0-9]*[a-z0-9])? which means the first character must be a lowercase letter, and all following characters must be a dash, lowercase letter, or digit, except the last character, which cannot be a dash.
description

string

An optional description of this resource. Provide this property when you create the resource.
backends[]

object

The list of backends that serve this BackendService.
backends[].description

string

An optional description of this resource. Provide this property when you create the resource.
backends[].group

string

The fully-qualified URL of an instance group or network endpoint group (NEG) resource. The type of backend that a backend service supports depends on the backend service's loadBalancingScheme.

  • When the loadBalancingScheme for the backend service is EXTERNAL, INTERNAL_SELF_MANAGED, or INTERNAL_MANAGED, the backend can be either an instance group or a NEG. The backends on the backend service must be either all instance groups or all NEGs. You cannot mix instance group and NEG backends on the same backend service.
  • When the loadBalancingScheme for the backend service is INTERNAL, the backend must be an instance group in the same region as the backend service. NEGs are not supported.

You must use the fully-qualified URL (starting with https://www.googleapis.com/) to specify the instance group or NEG. Partial URLs are not supported.
backends[].balancingMode

enum

Specifies the balancing mode for the backend.

When choosing a balancing mode, you need to consider the loadBalancingScheme, and protocol for the backend service, as well as the type of backend (instance group or NEG).

  • If the load balancing mode is CONNECTION, then the load is spread based on how many concurrent connections the backend can handle.

    You can use the CONNECTION balancing mode if the protocol for the backend service is SSL, TCP, or UDP.

    If the loadBalancingScheme for the backend service is EXTERNAL (SSL Proxy and TCP Proxy load balancers), you must also specify exactly one of the following parameters: maxConnections, maxConnectionsPerInstance, or maxConnectionsPerEndpoint.

    If the loadBalancingScheme for the backend service is INTERNAL (internal TCP/UDP load balancers), you cannot specify any additional parameters.

  • If the load balancing mode is RATE, the load is spread based on the rate of HTTP requests per second (RPS).

    You can use the RATE balancing mode if the protocol for the backend service is HTTP or HTTPS. You must specify exactly one of the following parameters: maxRate, maxRatePerInstance, or maxRatePerEndpoint.

  • If the load balancing mode is UTILIZATION, the load is spread based on the CPU utilization of instances in an instance group.

    You can use the UTILIZATION balancing mode if the loadBalancingScheme of the backend service is EXTERNAL, INTERNAL_SELF_MANAGED, or INTERNAL_MANAGED and the backends are instance groups. There are no restrictions on the backend service protocol.
backends[].maxUtilization

number

Defines the maximum average CPU utilization of a backend VM in an instance group. The valid range is [0.0, 1.0]. This is an optional parameter if the backend's balancingMode is UTILIZATION.

This parameter can be used in conjunction with maxRate, maxRatePerInstance, maxConnections, or maxConnectionsPerInstance.
backends[].maxRate

integer

The max requests per second (RPS) of the group. Can be used with either RATE or UTILIZATION balancing modes, but required if RATE mode. For RATE mode, either maxRate or maxRatePerInstance must be set.

This cannot be used for internal load balancing.
backends[].maxRatePerInstance

number

Defines a maximum target for requests per second (RPS) for a single VM in a backend instance group. This is multiplied by the number of instances in the instance group to implicitly calculate a target maximum rate for the whole instance group.

If the backend's balancingMode is UTILIZATION, this is an optional parameter. If the backend's balancingMode is RATE, you must specify either this parameter, maxRate, or maxRatePerEndpoint.

Not available if the backend's balancingMode is CONNECTION.
backends[].maxRatePerEndpoint

number

Defines a maximum target for requests per second (RPS) for an endpoint of a NEG. This is multiplied by the number of endpoints in the NEG to implicitly calculate a target maximum rate for the NEG.

If the backend's balancingMode is RATE, you must specify either this parameter, maxRate, or maxRatePerInstance.

Not available if the backend's balancingMode is CONNECTION.
backends[].maxConnections

integer

Defines a maximum target for simultaneous connections for the entire backend (instance group or NEG). If the backend's balancingMode is UTILIZATION, this is an optional parameter. If the backend's balancingMode is CONNECTION, and backend is attached to a backend service whose loadBalancingScheme is EXTERNAL, you must specify either this parameter, maxConnectionsPerInstance, or maxConnectionsPerEndpoint.

Not available if the backend's balancingMode is RATE. If the loadBalancingScheme is INTERNAL, then maxConnections is not supported, even though the backend requires a balancing mode of CONNECTION.
backends[].maxConnectionsPerInstance

integer

Defines a maximum target for simultaneous connections for a single VM in a backend instance group. This is multiplied by the number of instances in the instance group to implicitly calculate a target maximum number of simultaneous connections for the whole instance group. If the backend's balancingMode is UTILIZATION, this is an optional parameter. If the backend's balancingMode is CONNECTION, and backend is attached to a backend service whose loadBalancingScheme is EXTERNAL, you must specify either this parameter, maxConnections, or maxConnectionsPerEndpoint.

Not available if the backend's balancingMode is RATE. Internal TCP/UDP load balancing does not support setting maxConnectionsPerInstance even though its backends require a balancing mode of CONNECTION.
backends[].maxConnectionsPerEndpoint

integer

Defines a maximum target for simultaneous connections for an endpoint of a NEG. This is multiplied by the number of endpoints in the NEG to implicitly calculate a maximum number of target maximum simultaneous connections for the NEG. If the backend's balancingMode is CONNECTION, and the backend is attached to a backend service whose loadBalancingScheme is EXTERNAL, you must specify either this parameter, maxConnections, or maxConnectionsPerInstance.

Not available if the backend's balancingMode is RATE. Internal TCP/UDP load balancing does not support setting maxConnectionsPerEndpoint even though its backends require a balancing mode of CONNECTION.
backends[].capacityScaler

number

A multiplier applied to the group's maximum servicing capacity (based on UTILIZATION, RATE or CONNECTION). Default value is 1, which means the group will serve up to 100% of its configured capacity (depending on balancingMode). A setting of 0 means the group is completely drained, offering 0% of its available Capacity. Valid range is [0.0,1.0].

This cannot be used for internal load balancing.
healthChecks[]

string

The list of URLs to the HttpHealthCheck or HttpsHealthCheck resource for health checking this BackendService. Currently at most one health check can be specified. Health check is optional for Compute Engine backend services if there is no backend. A health check must not be specified when adding Internet Network Endpoint Group or Serverless Network Endpoint Group as backends. In all other cases, a health check is required for Compute Engine backend services.

For internal load balancing, a URL to a HealthCheck resource must be specified instead.
timeoutSec

integer

The backend service timeout has a different meaning depending on the type of load balancer. For more information read, Backend service settings The default is 30 seconds.
port
(deprecated)

integer

Deprecated in favor of portName. The TCP port to connect on the backend. The default value is 80.

This cannot be used if the loadBalancingScheme is INTERNAL (Internal TCP/UDP Load Balancing).
protocol

enum

The protocol this BackendService uses to communicate with backends.

Possible values are HTTP, HTTPS, HTTP2, TCP, SSL, or UDP. depending on the chosen load balancer or Traffic Director configuration. Refer to the documentation for the load balancer or for Traffic Director for more information.
fingerprint

string (bytes format)

Fingerprint of this resource. A hash of the contents stored in this object. This field is used in optimistic locking. This field will be ignored when inserting a BackendService. An up-to-date fingerprint must be provided in order to update the BackendService, otherwise the request will fail with error 412 conditionNotMet.

To see the latest fingerprint, make a get() request to retrieve a BackendService.

A base64-encoded string.
portName

string

A named port on a backend instance group representing the port for communication to the backend VMs in that group. Required when the loadBalancingScheme is EXTERNAL and the backends are instance groups. The named port must be defined on each backend instance group. This parameter has no meaning if the backends are NEGs.

Must be omitted when the loadBalancingScheme is INTERNAL (Internal TCP/UDP Load Blaancing).
enableCDN

boolean

If true, enables Cloud CDN for the backend service. Only applicable if the loadBalancingScheme is EXTERNAL and the protocol is HTTP or HTTPS.
sessionAffinity

enum

Type of session affinity to use. The default is NONE. Session affinity is not applicable if the --protocol is UDP.

When the loadBalancingScheme is EXTERNAL, possible values are NONE, CLIENT_IP, or GENERATED_COOKIE. You can use GENERATED_COOKIE if the protocol is HTTP or HTTPS.

When the loadBalancingScheme is INTERNAL, possible values are NONE, CLIENT_IP, CLIENT_IP_PROTO, or CLIENT_IP_PORT_PROTO.

When the loadBalancingScheme is INTERNAL_SELF_MANAGED, or INTERNAL_MANAGED, possible values are NONE, CLIENT_IP, GENERATED_COOKIE, HEADER_FIELD, or HTTP_COOKIE.
region

string

[Output Only] URL of the region where the regional backend service resides. This field is not applicable to global backend services. You must specify this field as part of the HTTP request URL. It is not settable as a field in the request body.
loadBalancingScheme

enum

Specifies the load balancer type. Choose EXTERNAL for load balancers that receive traffic from external clients. Choose INTERNAL for Internal TCP/UDP Load Balancing. Choose INTERNAL_MANAGED for Internal HTTP(S) Load Balancing. Choose INTERNAL_SELF_MANAGED for Traffic Director. A backend service created for one type of load balancing cannot be used with another. For more information, refer to Choosing a load balancer.
connectionDraining

object
connectionDraining.drainingTimeoutSec

integer

The amount of time in seconds to allow existing connections to persist while on unhealthy backend VMs. Only applicable if the protocol is not UDP. The valid range is [0, 3600].
iap

object
iap.enabled

boolean
iap.oauth2ClientId

string
iap.oauth2ClientSecret

string
iap.oauth2ClientSecretSha256

string

[Output Only] SHA256 hash value for the field oauth2ClientSecret above.
cdnPolicy

object

Cloud CDN configuration for this BackendService.
cdnPolicy.cacheKeyPolicy

object

The CacheKeyPolicy for this CdnPolicy.
cdnPolicy.cacheKeyPolicy.includeProtocol

boolean

If true, http and https requests will be cached separately.
cdnPolicy.cacheKeyPolicy.includeHost

boolean

If true, requests to different hosts will be cached separately.
cdnPolicy.cacheKeyPolicy.includeQueryString

boolean

If true, include query string parameters in the cache key according to queryStringWhitelist and queryStringBlacklist. If neither is set, the entire query string will be included. If false, the query string will be excluded from the cache key entirely.
cdnPolicy.cacheKeyPolicy.queryStringWhitelist[]

string

Names of query string parameters to include in cache keys. All other parameters will be excluded. Either specify queryStringWhitelist or queryStringBlacklist, not both. '&' and '=' will be percent encoded and not treated as delimiters.
cdnPolicy.cacheKeyPolicy.queryStringBlacklist[]

string

Names of query string parameters to exclude in cache keys. All other parameters will be included. Either specify queryStringWhitelist or queryStringBlacklist, not both. '&' and '=' will be percent encoded and not treated as delimiters.
cdnPolicy.signedUrlKeyNames[]

string

[Output Only] Names of the keys for signing request URLs.
cdnPolicy.signedUrlCacheMaxAgeSec

string (int64 format)

Maximum number of seconds the response to a signed URL request will be considered fresh. After this time period, the response will be revalidated before being served. Defaults to 1hr (3600s). When serving responses to signed URL requests, Cloud CDN will internally behave as though all responses from this backend had a "Cache-Control: public, max-age=[TTL]" header, regardless of any existing Cache-Control header. The actual headers served in responses will not be altered.
customRequestHeaders[]

string

Headers that the HTTP/S load balancer should add to proxied requests.
securityPolicy

string

[Output Only] The resource URL for the security policy associated with this backend service.
logConfig

object

This field denotes the logging options for the load balancer traffic served by this backend service. If logging is enabled, logs will be exported to Stackdriver.
logConfig.enable

boolean

This field denotes whether to enable logging for the load balancer traffic served by this backend service.
logConfig.sampleRate

number

This field can only be specified if logging is enabled for this backend service. The value of the field must be in [0, 1]. This configures the sampling rate of requests to the load balancer where 1.0 means all logged requests are reported and 0.0 means no logged requests are reported. The default value is 1.0.
localityLbPolicy

enum

The load balancing algorithm used within the scope of the locality. The possible values are:

  • ROUND_ROBIN: This is a simple policy in which each healthy backend is selected in round robin order. This is the default.
  • LEAST_REQUEST: An O(1) algorithm which selects two random healthy hosts and picks the host which has fewer active requests.
  • RING_HASH: The ring/modulo hash load balancer implements consistent hashing to backends. The algorithm has the property that the addition/removal of a host from a set of N hosts only affects 1/N of the requests.
  • RANDOM: The load balancer selects a random healthy host.
  • ORIGINAL_DESTINATION: Backend host is selected based on the client connection metadata, i.e., connections are opened to the same address as the destination address of the incoming connection before the connection was redirected to the load balancer.
  • MAGLEV: used as a drop in replacement for the ring hash load balancer. Maglev is not as stable as ring hash but has faster table lookup build times and host selection times. For more information about Maglev, refer to https://ai.google/research/pubs/pub44824

    • This field is applicable to either:

    • A regional backend service with the serviceProtocol set to HTTP, HTTPS, or HTTP2, and loadBalancingScheme set to INTERNAL_MANAGED.
    • A global backend service with the loadBalancingScheme set to INTERNAL_SELF_MANAGED.

    If sessionAffinity is not NONE, and this field is not set to >MAGLEV or RING_HASH, session affinity settings will not take effect.
consistentHash

object

Consistent Hash-based load balancing can be used to provide soft session affinity based on HTTP headers, cookies or other properties. This load balancing policy is applicable only for HTTP connections. The affinity to a particular destination host will be lost when one or more hosts are added/removed from the destination service. This field specifies parameters that control consistent hashing. This field is only applicable when localityLbPolicy is set to MAGLEV or RING_HASH.

This field is applicable to either:

  • A regional backend service with the serviceProtocol set to HTTP, HTTPS, or HTTP2, and loadBalancingScheme set to INTERNAL_MANAGED.
  • A global backend service with the loadBalancingScheme set to INTERNAL_SELF_MANAGED.
consistentHash.httpCookie

object

Hash is based on HTTP Cookie. This field describes a HTTP cookie that will be used as the hash key for the consistent hash load balancer. If the cookie is not present, it will be generated. This field is applicable if the sessionAffinity is set to HTTP_COOKIE.
consistentHash.httpCookie.name

string

Name of the cookie.
consistentHash.httpCookie.path

string

Path to set for the cookie.
consistentHash.httpCookie.ttl

object

Lifetime of the cookie.
consistentHash.httpCookie.ttl.seconds

string (int64 format)

Span of time at a resolution of a second. Must be from 0 to 315,576,000,000 inclusive. Note: these bounds are computed from: 60 sec/min * 60 min/hr * 24 hr/day * 365.25 days/year * 10000 years
consistentHash.httpCookie.ttl.nanos

integer

Span of time that's a fraction of a second at nanosecond resolution. Durations less than one second are represented with a 0 seconds field and a positive nanos field. Must be from 0 to 999,999,999 inclusive.
consistentHash.httpHeaderName

string

The hash based on the value of the specified header field. This field is applicable if the sessionAffinity is set to HEADER_FIELD.
consistentHash.minimumRingSize

string (int64 format)

The minimum number of virtual nodes to use for the hash ring. Defaults to 1024. Larger ring sizes result in more granular load distributions. If the number of hosts in the load balancing pool is larger than the ring size, each host will be assigned a single virtual node.
circuitBreakers

object

Settings controlling the volume of connections to a backend service. If not set, this feature is considered disabled.

This field is applicable to either:

  • A regional backend service with the serviceProtocol set to HTTP, HTTPS, or HTTP2, and loadBalancingScheme set to INTERNAL_MANAGED.
  • A global backend service with the loadBalancingScheme set to INTERNAL_SELF_MANAGED.
circuitBreakers.maxRequestsPerConnection

integer

Maximum requests for a single connection to the backend service. This parameter is respected by both the HTTP/1.1 and HTTP/2 implementations. If not specified, there is no limit. Setting this parameter to 1 will effectively disable keep alive.
circuitBreakers.maxConnections

integer

The maximum number of connections to the backend service. If not specified, there is no limit.
circuitBreakers.maxPendingRequests

integer

The maximum number of pending requests allowed to the backend service. If not specified, there is no limit.
circuitBreakers.maxRequests

integer

The maximum number of parallel requests that allowed to the backend service. If not specified, there is no limit.
circuitBreakers.maxRetries

integer

The maximum number of parallel retries allowed to the backend cluster. If not specified, the default is 1.
outlierDetection

object

Settings controlling the eviction of unhealthy hosts from the load balancing pool for the backend service. If not set, this feature is considered disabled.

This field is applicable to either:

  • A regional backend service with the serviceProtocol set to HTTP, HTTPS, or HTTP2, and loadBalancingScheme set to INTERNAL_MANAGED.
  • A global backend service with the loadBalancingScheme set to INTERNAL_SELF_MANAGED.
outlierDetection.consecutiveErrors

integer

Number of errors before a host is ejected from the connection pool. When the backend host is accessed over HTTP, a 5xx return code qualifies as an error. Defaults to 5.
outlierDetection.interval

object

Time interval between ejection analysis sweeps. This can result in both new ejections as well as hosts being returned to service. Defaults to 1 second.
outlierDetection.interval.seconds

string (int64 format)

Span of time at a resolution of a second. Must be from 0 to 315,576,000,000 inclusive. Note: these bounds are computed from: 60 sec/min * 60 min/hr * 24 hr/day * 365.25 days/year * 10000 years
outlierDetection.interval.nanos

integer

Span of time that's a fraction of a second at nanosecond resolution. Durations less than one second are represented with a 0 seconds field and a positive nanos field. Must be from 0 to 999,999,999 inclusive.
outlierDetection.baseEjectionTime

object

The base time that a host is ejected for. The real ejection time is equal to the base ejection time multiplied by the number of times the host has been ejected. Defaults to 30000ms or 30s.
outlierDetection.baseEjectionTime.seconds

string (int64 format)

Span of time at a resolution of a second. Must be from 0 to 315,576,000,000 inclusive. Note: these bounds are computed from: 60 sec/min * 60 min/hr * 24 hr/day * 365.25 days/year * 10000 years
outlierDetection.baseEjectionTime.nanos

integer

Span of time that's a fraction of a second at nanosecond resolution. Durations less than one second are represented with a 0 seconds field and a positive nanos field. Must be from 0 to 999,999,999 inclusive.
outlierDetection.maxEjectionPercent

integer

Maximum percentage of hosts in the load balancing pool for the backend service that can be ejected. Defaults to 50%.
outlierDetection.enforcingConsecutiveErrors

integer

The percentage chance that a host will be actually ejected when an outlier status is detected through consecutive 5xx. This setting can be used to disable ejection or to ramp it up slowly. Defaults to 0.
outlierDetection.enforcingSuccessRate

integer

The percentage chance that a host will be actually ejected when an outlier status is detected through success rate statistics. This setting can be used to disable ejection or to ramp it up slowly. Defaults to 100.
outlierDetection.successRateMinimumHosts

integer

The number of hosts in a cluster that must have enough request volume to detect success rate outliers. If the number of hosts is less than this setting, outlier detection via success rate statistics is not performed for any host in the cluster. Defaults to 5.
outlierDetection.successRateRequestVolume

integer

The minimum number of total requests that must be collected in one interval (as defined by the interval duration above) to include this host in success rate based outlier detection. If the volume is lower than this setting, outlier detection via success rate statistics is not performed for that host. Defaults to 100.
outlierDetection.successRateStdevFactor

integer

This factor is used to determine the ejection threshold for success rate outlier ejection. The ejection threshold is the difference between the mean success rate, and the product of this factor and the standard deviation of the mean success rate: mean - (stdev * successRateStdevFactor). This factor is divided by a thousand to get a double. That is, if the desired factor is 1.9, the runtime value should be 1900. Defaults to 1900.
outlierDetection.consecutiveGatewayFailure

integer

The number of consecutive gateway failures (502, 503, 504 status or connection errors that are mapped to one of those status codes) before a consecutive gateway failure ejection occurs. Defaults to 3.
outlierDetection.enforcingConsecutiveGatewayFailure

integer

The percentage chance that a host will be actually ejected when an outlier status is detected through consecutive gateway failures. This setting can be used to disable ejection or to ramp it up slowly. Defaults to 100.
network

string

The URL of the network to which this backend service belongs. This field can only be spcified when the load balancing scheme is set to INTERNAL.
kind

string

[Output Only] Type of resource. Always compute#backendService for backend services.

Methods

delete

 Deletes the specified regional BackendService resource.

get

 Returns the specified regional BackendService resource.

getHealth

 Gets the most recent health check results for this regional BackendService.

insert

 Creates a regional BackendService resource in the specified project using the data included in the request.

list

 Retrieves the list of regional BackendService resources available to the specified project in the given region.

patch

 Updates the specified regional BackendService resource with the data included in the request.

update

 Updates the specified regional BackendService resource with the data included in the request.