You can add a pool server to manage and share back-end servers flexibly and efficiently. A pool manages health check monitors and load balancer distribution methods.


  1. Click the Manage & Monitor tab and click Organization VDCs in the left pane.
  2. Double-click the organization virtual datacenter name to open the organization virtual datacenter.
  3. Click the Edge Gateways tab, right-click the edge gateway name, and select Edge Gateway Services.
  4. On the Load Balancer tab, click Pool Servers and click Add.
  5. Type a name and optionally a description for the pool server and click Next.
  6. Click Enable for each service to support.
  7. Select a balancing method from the drop-down menu for each enabled service.
    Option Description
    IP Hash

    Selects a server based on a hash of the source and destination IP address of each packet.

    Round Robin

    Each server is used in turn according to the weight assigned to it. This is the smoothest and fairest algorithm when the server's processing time remains equally distributed.


    The left part of the URI (before the question mark) is hashed and divided by the total weight of the running servers. The result designates which server will receive the request. This ensures that a URI is always directed to the same server as long as no server goes up or down.

    Least Connected

    Distributes client requests to multiple servers based on the number of connections already on the server. New connections are sent to the server with the fewest connections.

  8. (Optional) Change the default port for each enabled service if necessary.
  9. Click Next.
  10. Change the monitor port if required for each service that is to be supported by this pool.
  11. Select the health check mode from the drop-down menu for each service.
    Option Description

    Tests servers using SSLv3 client hello messages. The server is considered valid only when the response contains server hello messages.


    The GET / default method is used to detect server status. Only responses 2xx and 3xx are valid. Other responses (including a lack of response) indicate a server failure.

    TCP TCP connection check.
  12. (Optional) Change the default health check parameters if necessary.
    Option Description
    Interval Interval at which a server is pinged.
    Timeout Time within which a response from the server must be received.
    Health Threshold Number of consecutive successful health checks before a server is declared operational.
    Unhealth Threshold Number of consecutive unsuccessful health checks before a server is declared dead.
  13. For HTTP, type the URI referenced in the HTTP ping requests.
  14. Click Next.
  15. Click Add to add a back-end server to the pool.
  16. Type the IP address of the server.
  17. Type the weight to indicate the ratio of how many requests are to be served by this back-end server.
  18. Change the default port and monitor port for the server if required.
  19. Click OK.
  20. (Optional) Repeat Step 15 through Step 19 to add additional servers.
  21. Click Next.
  22. Verify that the settings for the pool server are correct and click Finish.