Add HighestRandomWeight Loadbalancing Algorithm

2025-09-08 12:00:42 +02:00 · 2025-09-08 12:00:42 +02:00 · 02443545e7
commit 02443545e7
parent 9b42b5b930
10 changed files with 936 additions and 112 deletions
--- a/docs/content/routing/services/index.md
+++ b/docs/content/routing/services/index.md
@ -175,6 +175,7 @@ Two load balancing algorithms are supported:

 - Weighed round-robin (wrr)
 - Power of two choices (p2c)
+- Highest Random Weight (hrw)

 ##### WRR

@ -242,6 +243,34 @@ Power of two choices algorithm is a load balancing strategy that selects two ser
          url = "http://private-ip-server-3/"
    ```

+##### HRW
+
+HighestRandomWeight, also called RendezVous hashing allows to loadbalance clients in a pool of services or servers.
+
+??? example "Load Balancing HRW with-- Using the [File Provider](../../providers/file.md)"
+
+    ```yaml tab="YAML"
+    ## Dynamic configuration
+    http:
+      services:
+        my-service:
+          loadBalancer:
+            type: hrw
+            servers:
+            - url: "http://private-ip-server-1/"
+            - url: "http://private-ip-server-2/"
+    ```
+
+    ```toml tab="TOML"
+    ## Dynamic configuration
+    [http.services]
+      [http.services.my-service.loadBalancer]
+        [[http.services.my-service.loadBalancer.servers]]
+          url = "http://private-ip-server-1/"
+        [[http.services.my-service.loadBalancer.servers]]
+          url = "http://private-ip-server-2/"
+    ```
+
 #### Sticky sessions

 When sticky sessions are enabled, a `Set-Cookie` header is set on the initial response to let the client know which server handles the first response.
@ -1253,6 +1282,147 @@ http:
        url = "http://private-ip-server-2/"
 ```

+### Highest Random Weight (service)
+
+The HRW is able to load balance the requests between multiple services based on weights.
+
+This strategy is only available to load balance between [services](./index.md) and not between [servers](./index.md#servers).
+
+!!! info "Supported Providers"
+
+    This strategy can be defined currently with the [File](../../providers/file.md) or [IngressRoute](../../providers/kubernetes-crd.md) providers.
+
+```yaml tab="YAML"
+## Dynamic configuration
+http:
+  services:
+    app:
+      highestRandomWeight:
+        services:
+        - name: appv1
+          weight: 3
+        - name: appv2
+          weight: 1
+
+    appv1:
+      loadBalancer:
+        type: hrw
+        servers:
+        - url: "http://private-ip-server-1/"
+
+    appv2:
+      loadBalancer:
+        type: hrw
+        servers:
+        - url: "http://private-ip-server-2/"
+```
+
+```toml tab="TOML"
+## Dynamic configuration
+[http.services]
+  [http.services.app]
+    [[http.services.app.highestRandomWeight.services]]
+      name = "appv1"
+      weight = 3
+    [[http.services.app.highestRandomWeight.services]]
+      name = "appv2"
+      weight = 1
+
+  [http.services.appv1]
+    [http.services.appv1.loadBalancer]
+      type = "hrw"
+      [[http.services.appv1.loadBalancer.servers]]
+        url = "http://private-ip-server-1/"
+
+  [http.services.appv2]
+    [http.services.appv2.loadBalancer]
+      type = "hrw"
+      [[http.services.appv2.loadBalancer.servers]]
+        url = "http://private-ip-server-2/"
+```
+
+#### Health Check
+
+HealthCheck enables automatic self-healthcheck for this service, i.e. whenever
+one of its children is reported as down, this service becomes aware of it, and
+takes it into account (i.e. it ignores the down child) when running the
+load-balancing algorithm. In addition, if the parent of this service also has
+HealthCheck enabled, this service reports to its parent any status change.
+
+!!! info "All or nothing"
+
+    If HealthCheck is enabled for a given service, but any of its descendants does
+    not have it enabled, the creation of the service will fail.
+
+    HealthCheck on Weighted services can be defined currently only with the [File](../../providers/file.md) provider.
+
+```yaml tab="YAML"
+## Dynamic configuration
+http:
+  services:
+    app:
+      highestRandomWeight:
+        healthCheck: {}
+        services:
+        - name: appv1
+          weight: 3
+        - name: appv2
+          weight: 1
+
+    appv1:
+      loadBalancer:
+        type: hrw
+        healthCheck:
+          path: /status
+          interval: 10s
+          timeout: 3s
+        servers:
+        - url: "http://private-ip-server-1/"
+
+    appv2:
+      loadBalancer:
+        type: hrw
+        healthCheck:
+          path: /status
+          interval: 10s
+          timeout: 3s
+        servers:
+        - url: "http://private-ip-server-2/"
+```
+
+```toml tab="TOML"
+## Dynamic configuration
+[http.services]
+  [http.services.app]
+    [http.services.app.highestRandomWeight.healthCheck]
+    [[http.services.app.highestRandomWeight.services]]
+      name = "appv1"
+      weight = 3
+    [[http.services.app.highestRandomWeight.services]]
+      name = "appv2"
+      weight = 1
+
+  [http.services.appv1]
+    [http.services.appv1.loadBalancer]
+      type="hrw"
+      [http.services.appv1.loadBalancer.healthCheck]
+        path = "/health"
+        interval = "10s"
+        timeout = "3s"
+      [[http.services.appv1.loadBalancer.servers]]
+        url = "http://private-ip-server-1/"
+
+  [http.services.appv2]
+    [http.services.appv2.loadBalancer]
+      type="hrw"
+      [http.services.appv2.loadBalancer.healthCheck]
+        path = "/health"
+        interval = "10s"
+        timeout = "3s"
+      [[http.services.appv2.loadBalancer.servers]]
+        url = "http://private-ip-server-2/"
+```
+
 ### Mirroring (service)

 The mirroring is able to mirror requests sent to a service to other services.