This section displays all the settings available for the current GSLB farm, organized into four tabs: Global, Services, Zones, and IPDS. To apply any changes made in this section, click the Submit button.

Global Settings for GSLB Farms #

When creating this form, you will encounter the following fields:

Name. This is the identification field and description of a virtual service. It is only editable if the GSLB farm is down. Ensure the new farm name is available before configuring it, or an error message will appear.

Virtual IP. The IP address used by the GSLB service. Ensure the new virtual IP is not already in use before making changes to this field.

Virtual Port. The IP port used by the GSLB service. Ensure the new virtual port is not already in use before making changes to this field.

The Actions buttons at the top right corner can also be used to manage the GSLB farm.

These icons allow you to restart (small curved arrows) or start/stop the farm (green triangle or square).

The Status is indicated using the following colors:

• Green: UP. The farm is running, and all backends are UP.
• Red: DOWN. The farm has stopped.
• Black: CRITICAL. The farm is UP, but no backend is available, or they are in maintenance mode.
• Blue: PROBLEM. The farm is running, but at least one backend is down.
• Orange: MAINTENANCE. The farm is running, but at least one backend is in maintenance mode.

These color codes are consistent throughout the graphical user interface. For more details, see the LSLB Farms Section.

Services Section in GSLB Farms #

Adding a New Service requires the following details:

Service Name: A short descriptive name for the new service.
Algorithm: The preferred load balancing method for the new service.

• Round Robin: Equal Sharing. Balances the traffic equally among all the active servers at the DNS layer. For every incoming connection, the balancer assigns the next round to a server.
  
• Priority: Connections forwarded to the backend with the highest priority. All connections are directed to the highest priority server. If this server is down, connections switch to the next highest priority server. This algorithm allows you to build an Active-Passive high availability cluster service with several real servers. The GSLB Priority service enables the creation of a global DNS clustering service at the domain name level. This service permits the same configuration options as Round Robin but allows only 2 backends to create a two-node cluster. By default, the local IP address 127.0.0.1 is configured and should be modified with the real server’s IP address.
  

Configuration options for both service types include:

Default TCP Port Health Check: The TCP port that the service will check to determine if the backend service is alive. This field cannot be left blank.
Farmguardian: Configure the default health check for the backends. More information is provided below.

Farmguardian #

Health Checks for the backend performed by Farmguardian are an optional advanced feature. Even if you do not enable it, a simple check will be performed every 5 seconds to monitor the backend status.

Some built-in or customized advanced health checks can be assigned to this service from the already created Farmguardian checks.

For further information about Farmguardian, refer to the Monitoring > Farmguardian section.

Once a Farmguardian is selected, it will be automatically applied to the farm.

Backends #

In the Backends section, at least one backend must be configured. By default, the 127.0.0.1 local IP address is set, but you will need to change it later.

GSLB farms allow you to configure the following real server properties:

Alias. If an alias has been defined for the backend, this field will show it.
IP. The IP address of the backend. If an alias is selected, this field will not be editable. To change it, modify the alias field instead. If Custom IP is selected in the alias field, this field will be editable for entering a custom IP address.
Action. Use the following actions for the selected backends.

• Add Backend. Opens the form to add a new backend to the service.
• Edit. Opens the backend form to change the backend configuration.
• Delete. Deletes the real server from the virtual service. The alias is not deleted. Note that deleting the first backend from the list is not allowed.

The backends of Priority services lack available actions. You can only Edit them.

GSLB Farms Zones #

A GSLB Zone describes a DNS domain name, including subdomains and aliases, necessary for generating a complete DNS zone with additional load balancing records using the defined services.

Once a new Zone is created for a specific domain, additional configuration options become available. Details are provided below.

Default Name Server: This sets the root name server entry point, also known as the Start Of Authority (SOA) DNS record. By default, it is set to ns1.

Zone Resources Configuration #

Every Zone requires creating Resources to configure the dynamic DNS:

Name: The resource name of the DNS entry.
TTL: Optional Time to Live (TTL) value for the current record, determining how long the name will be cached.
Type: DNS record type. Options include:

• A: Address type record returns an IPv4 address of a host.
• NS: Name Server type record delegates a DNS zone to use the given authoritative name servers.
• AAAA: Address type record returns an IPv6 address of a host.
• CNAME: Canonical name type record represents an alias of a given name.
• MX: Mail exchange type record maps a domain name to a list of message transfer agents for that domain.
• SRV: Generalized service location record used for newer protocols instead of creating protocol-specific records such as MX.
• TXT: Text type record used to store any text-based information, commonly for SPF data and domain ownership verification.
• PTR: Pointer record, a pointer to a canonical name used for reverse DNS lookups.
• NAPTR: Naming Authority Pointer allows regular-expression-based rewriting of domain names for URIs and domain name lookups.
• Services: Dynamic address (DYNA) type record returns a dynamic address specified by a Service already created within the farm configuration, according to the selected algorithm for that service. The TTL syntax for DYNA/DYNC records is MAX[/MIN], where MIN defaults to half of MAX if not explicitly specified.

Data: This field contains the actual data required by the record type. The input value depends on the type of Resource Name. The following example illustrates the various types of Resource Names and the permissible data values for each.

Allowed Data are:

• IPv4 address for A type.
• IPv6 address for AAAA type.
• Name server for NS type.
• Domain format for CNAME type (e.g., foo.bar.com).
• Domain format for MX type (e.g., mail.example.com).
• <priority> <weight> <port> <target> separated by blank spaces for SRV type (e.g., 20 30 334 my.target.com).
• Domain format for PTR type (e.g., foo.bar.com).
• <order> <preference|flags|services|regexp|replacement> for NAPTR type.
• Service name for Service type.

Action:

• Create Resource. Create a new resource record for a certain zone.
• Delete. Delete a resource record for a certain zone.
• Edit. Modify a certain resource value and apply.

IPDS #

This section allows you to enable IPDS rules. The list displays various types of protection with a select box to activate them. For detailed information, refer to the IPDS > Blacklists rules, IPDS > DoS rules, or IPDS > RBL rules specific documentation.

Each type of IPDS rule (Blacklist, DoS, RBL) features two tables: Available and Enabled, along with a chain icon that directs to its respective IPDS section. The Available table lists all applicable rules that can be applied to the farm. In the Enabled table, each rule applied to the farm is listed with a status indicator: red for stopped and green for running.

Clicking on the rule’s name allows modification of its parameters or the ability to start/stop the rule. Rules cannot be created directly from this farm view; instead, use the IPDS section.

To add a rule, select the desired rule and click the right single arrow. For multiple rules, hold the shift key while selecting and then click the right single arrow. To add all available blacklists, click the right double arrow.

To delete one or more rules, select them and click the left arrow. Use the double arrow to remove all selected rules.

Next step, check out the GSLB Stats and Graphs.