Define external addresses of server pools

Define the external address of a server pool as a property of the Server Pool element.

Clients make their incoming connections to the address of the Server Pool. The Firewall decides which server handles the connection and translates (in a NAT operation) the public address to the private IP address of that server. The external address or addresses of the Server Pool are defined as properties of the Server Pool element.

Note: Make sure that other NAT configurations do not overlap with the NAT of the Server Pool.

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

Steps

Select Configuration, then browse to SD-WAN.
Browse to Traffic Handlers.
Right-click a Server Pool element, then select Properties.
In the External Addresses section, click Add.
Select a NetLink element, or if you want to configure load sharing without traffic balancing between NetLinks, select Not Specified.
From the Network drop-down list, select the Network element that is used for the Server Pool’s external NATed address.
In the IP Address field, enter the external NATed destination IP address for the Server Pool.
Client computers contact this address when accessing the service that the servers in the Server Pool offer.
Note: The IP address you enter here must be reserved for NAT and it must not be used by any equipment in your network. Remember to update your DNS server with any changes in IP addressing.
From the Status drop-down list, select Enabled.
(Recommended) Select Proxy ARP Entry Generation to automatically generate a proxy ARP for the NATed address in the selected Network. Otherwise, define the ARP entry manually in the Firewall element properties.
Click OK.

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.

External Address dialog box

Use this dialog box to define the external address of a Server Pool as a property of the Server Pool element.

Option	Definition
NetLink	Select the NetLink you want to use, or if you want to configure load sharing for the servers but no traffic balancing between NetLinks, select Not Specified.
Network	Select the Network element that is used for the Server Pool’s external NATed address.
IP address	Specifies the external NATed destination IP address for the Server Pool.
Status	Select the Netlink status: Enabled or Disabled. Enabled NetLinks are used in the Server Pool.
Proxy ARP Entry Generation	When enabled, automatically generates a proxy ARP for the NATed address in the selected Network.