Add members to Server Pool elements

Add Host elements to Server Pool elements to balance traffic between the servers.

Before you begin

You must have a Host element for the internal IP address of each member of the server pool.

The Firewall uses the internal IP address of each member of the server pool to select which server handles which traffic that arrives at the server pool’s external address. When you define a Host element, you enter the IP address that the firewall uses to contact the server. Only Hosts with IPv4 addresses can be used in the server pool.

The server pool can have any number of members. If you have only one server and you want to balance the inbound traffic between your NetLinks, you can define a server pool with just one Host. This approach allows dynamic DNS update Information to be used to prevent contacting clients from attempting to use a NetLink that is out of service.

  For more details about the product and how to configure features, click Help or press F1.

Steps

  1. Select Configuration, then browse to SD-WAN.
  2. Browse to Traffic Handlers.
  3. Right-click Traffic Handlers and select New > Server Pool.
  4. In the Server Pool Members section, click Add.
  5. Select the elements for the members of the server pool.
    • Select an existing Server element (for servers that have some special role in the SMC configuration) or Host element (for other servers).
    • Select Tools > New to create an element.
  6. From the Allocate Traffic to Servers by drop-down list, select the granularity for the server selection.
    The granularity defines how likely it is that traffic is redirected to a particular server. Usually it is best to choose the least granular option that still produces an acceptable distribution of traffic. The options are (from least granular to most granular):
    Note:

    Consider the type of traffic when selecting the allocation method. Connections from the same source might be directed to different servers in the following cases:

    • Using the Host setting if the host’s IP address apparent to the SMC can change.
    • Using the Connection setting in all cases.

    Depending on the services offered, this behavior might deteriorate service quality.

Server Pool Properties dialog box

Use this dialog box to define Server Pools.

Option Definition
General tab
Name

(Optional)

Specifies the Server Pool name.
Category Categories allow you to flexibly filter your Management Client view.
Select

(Optional)

Opens the Category Selection dialog box.
Comment An optional comment for your own reference.
Option Definition
External Addresses section
NetLink Specifies the NetLink you want to use.
IP Address Specifies the external NATed destination IP address for the Server Pool.
Status Shows the NetLink status: Enabled or Disabled. Enabled NetLinks are used in the Server Pool.
Proxy ARP Entry When enabled, automatically generates a proxy ARP for the NATed address in the selected Network.
Add Opens the External Address dialog box.
Edit Opens the External Address dialog box and allows you to change the settings for the selected NetLink.
Remove Removes the selected external address.
Enable Dynamic DNS Updates Enables Dynamic DNS Updates from the Server Pool to the DNS Server.
DNS Server Select the External DNS Server element to which the DDNS updates are sent.
Fully Qualified Domain Name

Enter the Fully Qualified Domain Name for the Server Pool service (for example, “www.example.com”).

Option Definition
Server Pool Members section
Element Shows the names of the elements selected as pool members.
IP Address Shows the IP addresses of the elements selected as pool members.
Up Moves the element up the list.
Down Moves the rule position down the list.
Add Opens the Select Element dialog box.
Remove Removes the selected element from the Server Pool Members list.
Allocate Traffic to Servers by

Select the granularity for the server selection (defines how likely it is that traffic is redirected to a particular server). Usually it is best to choose the least granular option that still produces an acceptable distribution of traffic. The options are (from least granular to most granular):

  • Not Defined — Not Defined has the same effect as the Source Network option.
  • Source Network — Source Network directs traffic coming from the same C-class network to the same server. This option is a good choice when connections come from many different networks.
  • Host — Host directs traffic coming from the same IP address to the same server. This option is a good choice when a large portion of connections come from different hosts in the same C-class network.
  • Connection — Connection makes a new traffic management decision for each new connection. This choice might be necessary if a large portion of connections uses just one IP address.
  • Order — Allocate Traffic based on the order of the elements on the list.
Option Definition
Monitoring tab
Frequency Check Specifies how often you want the availability to be checked.
Method Specifies the method for monitoring the availability of the servers in the Server Pool.
  • Ping — Uses ICMP echo request (ping) messages to monitor the availability of the servers.
  • Agent — Uses the Server Pool Monitoring Agent feature. Before enabling this method, make sure that you have installed and configured the Monitoring Agents on all servers.
  • TCP — Checks that a specific TCP service is available.
  • HTTP — Checks that the HTTP service is available.
Option Definition
When Method is Agent
Port Defines the port number.
Option Definition
When Method is TCP
Port Defines the port number.
Request

(Optional)

 Specifies the string of ASCII text that the firewall sends.
Response

(Optional)

 Specifies the string of ASCII text that you expect to receive.
Option Definition
When Method is HTTP
Port Defines the port number.
Path Specifies the path to the webpage.
Host Header

(Optional)

 Specifies the host name of the web server.
Response

(Optional)

 Specifies the string of ASCII text that you expect to receive.