This section provides examples that illustrate how to set Edge-LB pool configuration options for path-based routing of inbound traffic.

Before you begin

Before you create Edge-LB pools and pool configuration files, you should have DC/OS™ Enterprise cluster nodes installed and ready to use and have previously downloaded and installed the latest Edge-LB packages.

• Edge-LB installed as described in the Edge-LB installation instructions.
• The core DC/OS command-line interface (CLI) installed and configured to communicate with the DC/OS cluster.
• The edgelb command-line interface (CLI) installed.
• An active and properly-configured DC/OS Enterprise cluster, with at least one DC/OS private agent node to run the load-balanced service and at least one DC/OS public agent node for exposing the load-balanced service.

For information about installing Edge-LB packages, see the installation instructions.

Path-based routing

This pool configures a load balancer which sends traffic to the httpd backend unless the path begins with /nginx, in which case it sends traffic to the nginx backend. The path in the request is rewritten before getting sent to nginx.

{
  "apiVersion": "V2",
  "name": "path-routing",
  "count": 1,
  "haproxy": {
    "frontends": [{
      "bindPort": 80,
      "protocol": "HTTP",
      "linkBackend": {
        "defaultBackend": "httpd",
        "map": [{
          "pathBeg": "/nginx",
          "backend": "nginx"
        }]
      }
    }],
    "backends": [{
      "name": "httpd",
      "protocol": "HTTP",
      "services": [{
        "marathon": {
          "serviceID": "/host-httpd"
        },
        "endpoint": {
          "portName": "web"
        }
      }]
    },{
      "name": "nginx",
      "protocol": "HTTP",
      "rewriteHttp": {
        "path": {
          "fromPath": "/nginx",
          "toPath": "/"
        }
      },
      "services": [{
        "mesos": {
          "frameworkName": "marathon",
          "taskName": "bridge-nginx"
        },
        "endpoint": {
          "portName": "web"
        }
      }]
    }]
  }
}

Modifying path values

The following examples illustrate how the path would be changed for different fromPath and toPath values:

• fromPath: "/nginx", toPath: "", request: /nginx --> /
• fromPath: "/nginx", toPath: "/", request: /nginx --> /
• fromPath: "/nginx", toPath: "/", request: /nginx/ --> /
• fromPath: "/nginx", toPath: "/", request: /nginx/index.html --> /index.html
• fromPath: "/nginx", toPath: "/", request: /nginx/subpath/index.html --> /subpath/index.html
• fromPath: "/nginx/", toPath: "", request: /nginx --> /nginx (The path is not rewritten in this case because the request did not match /nginx/)
• fromPath: "/nginx/", toPath: "", request: /nginx/ --> /
• fromPath: "/nginx", toPath: "/subpath", request: /nginx --> /subpath
• fromPath: "/nginx", toPath: "/subpath", request: /nginx/ --> /subpath/
• fromPath: "/nginx", toPath: "/subpath", request: /nginx/index.html --> /subpath/index.html
• fromPath: "/nginx", toPath: "/subpath/", request: /nginx/index.html --> /subpath//index.html (Note that for cases other than toPath: "" or toPath: "/", it is suggested that the fromPath and toPath either both end in /, or neither do, because the rewritten path could otherwise end up with a double slash.)
• fromPath: "/nginx/", toPath: "/subpath/", request: /nginx/index.html --> /subpath/index.html

This example uses pool.haproxy.frontend.linkBackend.pathBeg to match on the beginning of a path. Other useful fields are:

• pathBeg: Match on path beginning
• pathEnd: Match on path ending
• pathReg: Match on a path regular expression