[Документация Yandex Cloud](../../index.md) > [Yandex Managed Service for Kubernetes](../index.md) > Инструменты Application Load Balancer > Gwin > Конфигурация ресурсов (англ.) > GRPCRoute
# GRPCRoute
GRPCRoute provides a way to route gRPC requests. This includes the capability to match requests by hostname, gRPC service, or method. Requests are routed to backend services that support gRPC.
GRPCRoute is a [Kubernetes Gateway API](https://gateway-api.sigs.k8s.io/) project resource. Below, we describe its fields and annotations used by Gwin. For configuration details, see the [upstream documentation](https://gateway-api.sigs.k8s.io/reference/spec/#gateway.networking.k8s.io/v1.GRPCRoute).
GRPCRoute resources must be attached to [Gateway](gateway.md) resources to function properly.
* [Cheatsheet](#cheatsheet)
* [GRPCRouteMeta](#grpcroutemeta)
* [Annotations cheatsheet](#annotations-cheatsheet)
* [Annotations reference](#annotations-reference)
* [GRPCRouteSpec](#grpcroutespec)
* [ParentReference](#parentreference)
* [GRPCRouteRule](#grpcrouterule)
* [GRPCRouteMatch](#grpcroutematch)
* [GRPCMethodMatch](#grpcmethodmatch)
* [GRPCHeaderMatch](#grpcheadermatch)
* [GRPCRouteFilter](#grpcroutefilter)
* [GRPCHeaderFilter](#grpcheaderfilter)
* [GRPCBackendRef](#grpcbackendref)
## Cheatsheet
{% note info %}
Specification provided below is not valid configuration.
It's just demonstration of all `GRPCRoute` fields.
{% endnote %}
```yaml
apiVersion: gateway.networking.k8s.io/v1
kind: GRPCRoute
metadata:
name: example-grpc-route
namespace: example-ns
annotations: ... # see annotations example below
spec:
parentRefs: # attach to Gateway resources
- group: gateway.networking.k8s.io
kind: Gateway
namespace: gateway-ns
name: example-gateway
sectionName: grpc-listener # specific listener name
hostnames: # domains this route handles
- "grpc.example.com" # gRPC service domain
- "api.example.com" # API domain
rules:
- name: service-rule # rule identifier
matches: # conditions for this rule
- method:
type: Exact # exact method match
service: "example.UserService" # gRPC service
method: "GetUser" # gRPC method
- method:
type: RegularExpression # regex method match
method: "List.*" # match List* methods
- headers: # header matching
- name: "grpc-timeout"
value: "30s"
filters: # modify requests before routing
- type: RequestHeaderModifier
requestHeaderModifier:
set: # replace header values
- name: "x-custom-header"
value: "custom-value"
add: # add new headers
- name: "x-added-header"
value: "added-value"
remove: # remove headers
- "x-remove-header"
- type: ResponseHeaderModifier
responseHeaderModifier: ... # same as RequestHeaderModifier
backendRefs: # where to route requests
- group: "" # core Kubernetes API
kind: Service # Kubernetes service
name: grpc-service
namespace: grpc-ns
port: 9090
weight: 80 # 80% of traffic
- group: gwin.yandex.cloud # Gwin custom resources
name: grpc-backends
weight: 20 # 20% of traffic
```
| Field | Description |
|-------|-------------|
| metadata | **[GRPCRouteMeta](#grpcroutemeta)**
Name, namespace and annotations. |
| spec | **[GRPCRouteSpec](#grpcroutespec)**
Resource specification. |
## GRPCRouteMeta
*Appears in:* [GRPCRoute](#cheatsheet)
| Field | Description |
|-------|-------------|
| name | **string**
Name of the GRPCRoute. |
| namespace | **string**
Namespace of the GRPCRoute. |
| annotations | **map[string]string**
Annotations of the GRPCRoute. |
### Annotations cheatsheet
{% note info %}
You can also set policy parameters using [RoutePolicy](routepolicy.md) resource. The RoutePolicy resource parameters and GRPCRoute annotations are equivalent.
{% endnote %}
Specification provided below is not valid configuration.
It's just demonstration of all `GRPCRoute` annotations.
```yaml
apiVersion: gateway.networking.k8s.io/v1
kind: GRPCRoute
metadata:
annotations:
# Backend group configuration
gwin.yandex.cloud/rules.backends.balancing.mode: "ROUND_ROBIN" # load balancing algorithm
gwin.yandex.cloud/rules.backends.balancing.localityAwareRouting: "80" # prefer same zone
gwin.yandex.cloud/rules.backends.balancing.strictLocality: "false" # allow cross-zone routing
gwin.yandex.cloud/rules.backends.balancing.panicThreshold: "50" # panic mode threshold
# Health checks
gwin.yandex.cloud/rules.backends.hc.timeout: "5s" # health check timeout
gwin.yandex.cloud/rules.backends.hc.interval: "10s" # check interval
gwin.yandex.cloud/rules.backends.hc.healthyThreshold: "2" # checks to mark healthy
gwin.yandex.cloud/rules.backends.hc.unhealthyThreshold: "3" # checks to mark unhealthy
gwin.yandex.cloud/rules.backends.hc.port: "9090" # health check port
gwin.yandex.cloud/rules.backends.hc.grpc.serviceName: "health.HealthService" # gRPC service
# Health check transport settings
gwin.yandex.cloud/rules.backends.hc.transportSettings.plaintext: "true" # use plaintext for health checks
gwin.yandex.cloud/rules.backends.hc.transportSettings.tls.sni: "health.example.com" # SNI for health check TLS
gwin.yandex.cloud/rules.backends.hc.transportSettings.tls.trustedCA.id: "health-cert-123" # health check TLS cert ID
gwin.yandex.cloud/rules.backends.hc.transportSettings.tls.trustedCA.bytes: "-----BEGIN CERTIFICATE-----..." # health check TLS cert PEM
# Backend TLS configuration
gwin.yandex.cloud/rules.backends.tls.sni: "grpc.example.com" # SNI for TLS
gwin.yandex.cloud/rules.backends.tls.trustedCA.id: "cert-123456" # cloud certificate ID
gwin.yandex.cloud/rules.backends.tls.trustedCA.bytes: "-----BEGIN CERTIFICATE-----..." # PEM certificate
# Session affinity
gwin.yandex.cloud/rules.sessionAffinity.header.name: "X-Session-ID" # header-based affinity
gwin.yandex.cloud/rules.sessionAffinity.cookie.name: "session" # cookie name
gwin.yandex.cloud/rules.sessionAffinity.cookie.ttl: "3600s" # cookie lifetime
gwin.yandex.cloud/rules.sessionAffinity.cookie.path: "/app" # cookie path attribute
gwin.yandex.cloud/rules.sessionAffinity.sourceIP: "true" # IP-based affinity
# Route timeouts
gwin.yandex.cloud/rules.timeout: "60s" # overall connection timeout
gwin.yandex.cloud/rules.idleTimeout: "300s" # idle connection timeout
# Host rewriting
gwin.yandex.cloud/rules.hostRewrite.auto: "true" # automatically rewrite host to backend target
gwin.yandex.cloud/rules.hostRewrite.replace: "grpc.backend.example.com" # static host replacement
# Security
gwin.yandex.cloud/hosts.securityProfileID: "host-security-profile-1" # Yandex Smart Web Security profile for hosts
# Rate limiting
gwin.yandex.cloud/rules.rateLimit.allRequests.perSecond: "100" # route-level rate limit for all requests
gwin.yandex.cloud/rules.rateLimit.allRequests.perMinute: "6000" # route-level rate limit for all requests
gwin.yandex.cloud/rules.rateLimit.requestsPerIP.perSecond: "10" # route-level rate limit per IP
gwin.yandex.cloud/rules.rateLimit.requestsPerIP.perMinute: "600" # route-level rate limit per IP
gwin.yandex.cloud/hosts.rateLimit.allRequests.perSecond: "100" # host-level rate limit for all requests
gwin.yandex.cloud/hosts.rateLimit.allRequests.perMinute: "6000" # host-level rate limit for all requests
gwin.yandex.cloud/hosts.rateLimit.requestsPerIP.perSecond: "10" # host-level rate limit per IP
gwin.yandex.cloud/hosts.rateLimit.requestsPerIP.perMinute: "600" # host-level rate limit per IP
# RBAC configuration
gwin.yandex.cloud/rules.rbac.action: "ALLOW" # default RBAC action
gwin.yandex.cloud/rules.rbac.principals.admin.check-token.header.name: "authorization" # header to check
gwin.yandex.cloud/rules.rbac.principals.admin.check-token.header.exact: "Bearer admin123" # required value
gwin.yandex.cloud/rules.rbac.principals.admin.check-ip.ip.remoteIp: "10.0.0.0/8" # allowed IP range
gwin.yandex.cloud/hosts.rbac.action: "DENY" # host-level RBAC action
# Rule-specific configuration (conflict with global settings is an error)
gwin.yandex.cloud/rule.service-rule.backends.balancing.mode: "LEAST_REQUEST" # per-rule balancing
gwin.yandex.cloud/rule.service-rule.timeout: "30s" # per-rule timeout
gwin.yandex.cloud/rule.service-rule.idleTimeout: "120s" # per-rule idle timeout
gwin.yandex.cloud/rule.service-rule.attach.backendGroup.id: "backend-group-id-1" # per-rule attach
# Per-backend configuration by index
gwin.yandex.cloud/rule.service-rule.backend.0.tls.sni: "backend-0.example.com" # TLS SNI for first backend
gwin.yandex.cloud/rule.service-rule.backend.0.albBackendName: "my-backend-0" # custom name for first backend
# ALB resource naming
gwin.yandex.cloud/hosts.albVirtualHostName: "my-virtual-host" # custom virtual host name
gwin.yandex.cloud/rule.service-rule.albRouteName: "my-route" # custom route name
gwin.yandex.cloud/rule.service-rule.albBackendGroupName: "my-backend-group" # custom backend group name
```
### Annotations reference
#### Backend group configuration
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rules.backends.balancing.mode`
_(string)_
Load balancing mode for backend group. Possible values: `RANDOM`, `ROUND_ROBIN`, `LEAST_REQUEST`, `MAGLEV_HASH`.
Example: `ROUND_ROBIN` |
| `gwin.yandex.cloud/rules.backends.balancing.localityAwareRouting`
_(number)_
Percentage of traffic sent to backends in the same availability zone.
Example: `80` |
| `gwin.yandex.cloud/rules.backends.balancing.strictLocality`
_(boolean)_
Route traffic only to backends in the same availability zone.
Example: `false` |
| `gwin.yandex.cloud/rules.backends.balancing.panicThreshold`
_(number)_
Panic mode threshold percentage for load balancing.
Example: `50` |
#### Health check configuration
##### Common health check settings
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rules.backends.hc.timeout`
_(duration)_
Health check timeout.
Example: `5s` |
| `gwin.yandex.cloud/rules.backends.hc.interval`
_(duration)_
Interval between health checks.
Example: `10s` |
| `gwin.yandex.cloud/rules.backends.hc.healthyThreshold`
_(number)_
Number of successful checks to mark backend as healthy.
Example: `2` |
| `gwin.yandex.cloud/rules.backends.hc.unhealthyThreshold`
_(number)_
Number of failed checks to mark backend as unhealthy.
Example: `3` |
| `gwin.yandex.cloud/rules.backends.hc.port`
_(number)_
Port for health checks.
Example: `9090` |
##### gRPC health checks
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rules.backends.hc.grpc.serviceName`
_(string)_
gRPC service name for health checks.
Example: `health.HealthService` |
##### Health check transport settings
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rules.backends.hc.transportSettings.plaintext`
_(boolean)_
Use plaintext protocol for health checks. Set to `true` to force HTTP health checks even for HTTPS backends.
Example: `true` |
| `gwin.yandex.cloud/rules.backends.hc.transportSettings.tls.sni`
_(string)_
Server Name Indication (SNI) for health check TLS connections.
Example: `health.example.com` |
| `gwin.yandex.cloud/rules.backends.hc.transportSettings.tls.trustedCA.id`
_(string)_
Cloud certificate ID for health check TLS validation.
Example: `health-cert-123` |
| `gwin.yandex.cloud/rules.backends.hc.transportSettings.tls.trustedCA.bytes`
_(string)_
X.509 certificate contents in PEM format for health check TLS validation.
Example: `-----BEGIN CERTIFICATE-----...` |
#### Backend TLS configuration
TLS settings for backend connections. \
Use when the load balancer must connect to its targets over TLS. \
If you only need “TLS as is” (no SNI and no backend certificate verification), set `gwin.yandex.cloud/rules.backends.tls.sni: ""`. \
Health check TLS settings work the same way, but are configured separately.
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rules.backends.tls.sni`
_(string)_
Server Name Indication (SNI) for TLS connections to backends.
Example: `grpc.example.com` |
| `gwin.yandex.cloud/rules.backends.tls.trustedCA.id`
_(string)_
Cloud certificate ID for backend TLS validation.
Example: `cert-123456` |
| `gwin.yandex.cloud/rules.backends.tls.trustedCA.bytes`
_(string)_
X.509 certificate contents in PEM format for backend TLS validation.
Example: `-----BEGIN CERTIFICATE-----...` |
#### Session affinity
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rules.sessionAffinity.header.name`
_(string)_
HTTP header name for session affinity.
Example: `X-Session-ID` |
| `gwin.yandex.cloud/rules.sessionAffinity.cookie.name`
_(string)_
Cookie name for session affinity.
Example: `session` |
| `gwin.yandex.cloud/rules.sessionAffinity.cookie.ttl`
_(duration)_
Cookie TTL for session affinity.
Example: `3600s` |
| `gwin.yandex.cloud/rules.sessionAffinity.cookie.path`
_(string)_
Path attribute for the generated session cookie. If unspecified or empty, no path is set for the cookie.
Example: `/app` |
| `gwin.yandex.cloud/rules.sessionAffinity.sourceIP`
_(boolean)_
Use source IP for session affinity.
Example: `true` |
#### Route configuration
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rules.timeout`
_(duration)_
Overall timeout for gRPC connection between load balancer and backend.
Example: `60s` |
| `gwin.yandex.cloud/rules.idleTimeout`
_(duration)_
Idle timeout for gRPC connection.
Example: `300s` |
#### Route rate limiting
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rules.rateLimit.allRequests.perSecond`
_(number)_
Route-level rate limit for all requests per second.
Example: `100` |
| `gwin.yandex.cloud/rules.rateLimit.allRequests.perMinute`
_(number)_
Route-level rate limit for all requests per minute.
Example: `6000` |
| `gwin.yandex.cloud/rules.rateLimit.requestsPerIP.perSecond`
_(number)_
Route-level rate limit per IP address per second.
Example: `10` |
| `gwin.yandex.cloud/rules.rateLimit.requestsPerIP.perMinute`
_(number)_
Route-level rate limit per IP address per minute.
Example: `600` |
#### Host rewriting
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rules.hostRewrite.auto`
_(boolean)_
Automatically replaces the host with that of the target backend. Cannot be used together with `hostRewrite.replace`.
Example: `true` |
| `gwin.yandex.cloud/rules.hostRewrite.replace`
_(string)_
Static host replacement value for gRPC :authority pseudo-headers. Cannot be used together with `hostRewrite.auto`.
Example: `grpc.backend.example.com` |
#### Security configuration
| Annotation and description |
|------------|
| `gwin.yandex.cloud/hosts.securityProfileID`
_(string)_
Security profile ID for host-level protection.
Example: `host-security-profile-1` |
#### Rate limiting
| Annotation and description |
|------------|
| `gwin.yandex.cloud/hosts.rateLimit.allRequests.perSecond`
_(number)_
Rate limit for all requests per second.
Example: `100` |
| `gwin.yandex.cloud/hosts.rateLimit.allRequests.perMinute`
_(number)_
Rate limit for all requests per minute.
Example: `6000` |
| `gwin.yandex.cloud/hosts.rateLimit.requestsPerIP.perSecond`
_(number)_
Rate limit per IP address per second.
Example: `10` |
| `gwin.yandex.cloud/hosts.rateLimit.requestsPerIP.perMinute`
_(number)_
Rate limit per IP address per minute.
Example: `600` |
#### RBAC configuration
RBAC allows controlling access to routes or hosts based on request attributes.
Annotations follow the pattern:
`gwin.yandex.cloud/{resource}.rbac.principals.{principal-group}.{principal}.{rule-type}`
Where:
* `{resource}` — resource type (`rules`, `hosts`);
* `{principal-group}` — logical group of checks (e.g. `admin`);
* `{principal}` — specific principal identifier (e.g. `check-token`);
* `{rule-type}` — matching rule type (`header`, `ip`, etc.).
##### Combination Rules
* All checks within the same principal group are combined with AND logic.
* Different principal groups are combined with OR logic.
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rules.rbac.action`
_(string)_
Action when principals match (ALLOW/DENY) for route access control.
Example: `ALLOW` |
| `gwin.yandex.cloud/rules.rbac.principals.{group}.{principal}.header.name`
_(string)_
Header name to match for route RBAC.
Example: `authorization` |
| `gwin.yandex.cloud/rules.rbac.principals.{group}.{principal}.header.exact`
_(string)_
Exact header value match for route RBAC.
Example: `Bearer admin123` |
| `gwin.yandex.cloud/rules.rbac.principals.{group}.{principal}.header.regex`
_(string)_
Regex pattern for header value match for route RBAC.
Example: `^Bearer .*` |
| `gwin.yandex.cloud/rules.rbac.principals.{group}.{principal}.header.prefix`
_(string)_
Header value prefix match for route RBAC.
Example: `Bearer ` |
| `gwin.yandex.cloud/rules.rbac.principals.{group}.{principal}.ip.remoteIp`
_(string)_
IP address or CIDR block for route RBAC.
Example: `10.0.0.0/8` |
| `gwin.yandex.cloud/rules.rbac.principals.{group}.{principal}.any`
_(boolean)_
Match any request for route RBAC.
Example: `true` |
| `gwin.yandex.cloud/hosts.rbac.action`
_(string)_
Action when principals match (ALLOW/DENY) for host access control.
Example: `DENY` |
#### Rule-specific configuration
{% note info %}
Any `rules` option can be applied to a specific rule by prefixing with `rule.{rule-name}`.
For example: `gwin.yandex.cloud/rule.service-rule.backends.balancing.mode: "LEAST_REQUEST"`.
{% endnote %}
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rule.{rule-name}.backends.balancing.mode`
_(string)_
Load balancing mode for specific rule.
Example: `LEAST_REQUEST` |
| `gwin.yandex.cloud/rule.{rule-name}.timeout`
_(duration)_
Timeout for specific rule.
Example: `30s` |
| `gwin.yandex.cloud/rule.{rule-name}.idleTimeout`
_(duration)_
Idle timeout for specific rule.
Example: `120s` |
| `gwin.yandex.cloud/rule.{rule-name}.attach.backendGroup.id`
_(string)_
Cloud backend group ID for specific rule attachment.
Example: `backend-group-id-1` |
#### Per-backend configuration by index
{% note info %}
Any `rules.backends` option can be applied to a specific backend within a rule by using `rule.{rule-name}.backend.{index}`, where `{index}` is the zero-based position of the backend in the rule's `backendRefs` list.
For example: `gwin.yandex.cloud/rule.service-rule.backend.0.tls.sni: "backend-0.example.com"`.
{% endnote %}
| Annotation and description |
|------------|
| `gwin.yandex.cloud/rule.{rule-name}.backend.{index}.tls.sni`
_(string)_
SNI for TLS connections to the specific backend.
Example: `backend-0.example.com` |
| `gwin.yandex.cloud/rule.{rule-name}.backend.{index}.hc.grpc.serviceName`
_(string)_
gRPC health check service name for the specific backend.
Example: `health.HealthService` |
#### ALB resource naming
Custom names for ALB resources created by the controller. By default, the controller generates names automatically.
| Annotation and description |
|------------|
| `gwin.yandex.cloud/hosts.albVirtualHostName`
_(string)_
Custom name for the ALB virtual host.
Example: `my-virtual-host` |
| `gwin.yandex.cloud/rule.{rule-name}.albRouteName`
_(string)_
Custom name for the ALB route for the specified rule.
Example: `my-route` |
| `gwin.yandex.cloud/rule.{rule-name}.albBackendGroupName`
_(string)_
Custom name for the ALB backend group for the specified rule.
Example: `my-backend-group` |
| `gwin.yandex.cloud/rule.{rule-name}.backend.{index}.albBackendName`
_(string)_
Custom name for the ALB backend at the specified zero-based index within the rule's `backendRefs`.
Example: `my-backend` |
For the target group name, see [`gwin.yandex.cloud/albTargetGroupName`](service.md) on the Service resource.
## GRPCRouteSpec
GRPCRoute specification defines the desired state of GRPCRoute.
*Appears in:* [GRPCRoute](#cheatsheet)
| Field | Description |
|-------|-------------|
| parentRefs | **[[]ParentReference](#parentreference)**
References to Gateway resources that this GRPCRoute should attach to. |
| hostnames | **[]string**
Hostnames that should match against the gRPC :authority header. |
| rules | **[[]GRPCRouteRule](#grpcrouterule)**
Rules for routing gRPC requests. |
### ParentReference
Reference to a Gateway resource that this route should attach to.
*Appears in:* [GRPCRouteSpec](#grpcroutespec)
| Field | Description |
|-------|-------------|
| group | **string**
API group of the parent resource.
Example: `gateway.networking.k8s.io` |
| kind | **string**
Kind of the parent resource.
Example: `Gateway` |
| namespace | **string**
Namespace of the parent resource.
Example: `gateway-ns` |
| name | **string**
Name of the parent resource.
Example: `example-gateway` |
| sectionName | **string**
Name of the specific listener to attach to.
Example: `grpc-listener` |
| port | **int32**
Port number of the listener to attach to.
Example: `80` |
### GRPCRouteRule
GRPCRouteRule defines semantics for matching a gRPC request based on conditions (matches), processing it (filters), and forwarding the request to an API object (backendRefs).
*Appears in:* [GRPCRouteSpec](#grpcroutespec)
| Field | Description |
|-------|-------------|
| name | **string**
Name of the route rule. Must be unique within a Route if set.
Example: `service-rule` |
| matches | **[[]GRPCRouteMatch](#grpcroutematch)**
Conditions required for a request to match this rule. |
| filters | **[[]GRPCRouteFilter](#grpcroutefilter)**
Filters to modify requests before forwarding to backends. |
| backendRefs | **[[]GRPCBackendRef](#grpcbackendref)**
Backend services to route requests to. |
| sessionPersistence | **SessionPersistence**
Session persistence configuration for the route rule. |
### GRPCRouteMatch
GRPCRouteMatch defines the predicate used to match requests to a given action. Multiple match types are ANDed together.
*Appears in:* [GRPCRouteRule](#grpcrouterule)
| Field | Description |
|-------|-------------|
| method | **[GRPCMethodMatch](#grpcmethodmatch)**
gRPC method matcher. |
| headers | **[[]GRPCHeaderMatch](#grpcheadermatch)**
gRPC header matchers. |
### GRPCMethodMatch
GRPCMethodMatch describes how to select a gRPC route by matching the gRPC request method.
*Appears in:* [GRPCRouteMatch](#grpcroutematch)
| Field | Description |
|-------|-------------|
| type | **string**
Method match type. `Exact` for exact method match, `RegularExpression` for regex match.
Example: `Exact`, `RegularExpression`. |
| service | **string**
gRPC service name to match against.
Example: `example.UserService` |
| method | **string**
gRPC method name to match against. For regex type, this is a regular expression pattern.
Example: `GetUser`, `List.*`. |
### GRPCHeaderMatch
GRPCHeaderMatch describes how to select a gRPC route by matching gRPC request headers.
*Appears in:* [GRPCRouteMatch](#grpcroutematch)
| Field | Description |
|-------|-------------|
| type | **string**
Header match type. `Exact` for exact match, `RegularExpression` for regex match.
Example: `Exact`, `RegularExpression`. |
| name | **string**
Name of the gRPC header to be matched.
Example: `grpc-timeout` |
| value | **string**
Value of the gRPC header to be matched.
Example: `30s` |
### GRPCRouteFilter
GRPCRouteFilter defines processing steps that must be completed during the request or response lifecycle.
*Appears in:* [GRPCRouteRule](#grpcrouterule), [GRPCBackendRef](#grpcbackendref)
| Field | Description |
|-------|-------------|
| type | **string**
Filter type. Supported: `RequestHeaderModifier`, `ResponseHeaderModifier`, `RequestMirror`, `ExtensionRef`
Example: `RequestHeaderModifier` |
| requestHeaderModifier | **[GRPCHeaderFilter](#grpcheaderfilter)**
Request header modification configuration. |
| responseHeaderModifier | **[GRPCHeaderFilter](#grpcheaderfilter)**
Response header modification configuration. |
### GRPCHeaderFilter
GRPCHeaderFilter defines configuration for header modification filters (both RequestHeaderModifier and ResponseHeaderModifier).
*Appears in:* [GRPCRouteFilter](#grpcroutefilter)
| Field | Description |
|-------|-------------|
| set | **[]GRPCHeader**
Headers to set, replacing any existing values. |
| add | **[]GRPCHeader**
Headers to add to the request/response. |
| remove | **[]string**
Header names to remove from the request/response. |
### GRPCBackendRef
GRPCBackendRef defines how a GRPCRoute forwards a gRPC request.
*Appears in:* [GRPCRouteRule](#grpcrouterule)
| Field | Description |
|-------|-------------|
| group | **string**
API group of the backend resource.
Example: `""`, `gwin.yandex.cloud`. |
| kind | **string**
Kind of the backend resource.
Example: `Service` |
| name | **string**
Name of the backend resource.
Example: `grpc-service` |
| namespace | **string**
Namespace of the backend resource.
Example: `grpc-ns` |
| port | **int32**
Port of the backend service (for Service kind only).
Example: `9090` |
| weight | **int32**
Weight for traffic distribution between backends.
Example: `80` |