Recommended Settings and Best Practices for Generic Implementation of a NetScaler Appliance

This article contains recommended settings and best practices for a generic implementation of a NetScaler appliance.

Recommended Settings for a Generic Implementation of a NetScaler Appliance

The following sections contain the recommended settings for a generic implementation of a few features of a NetScaler appliance:

• Modes

• Features

• Global System Settings

• HTTP Parameters

• SNMP Alarms

• Network Interfaces

Modes

To configure the modes on an appliance, complete the following procedure:

1. Expand the System node of the Navigation pane on the appliance.

2. Select the Settings node.

3. Click the Change modes link on the Settings page, as shown in the following screen shot.

   

4. Select the Fast Ramp option.
   Note: With Fast-Ramp enabled the NetScaler starts with the congestion window of the freshest server connection. For more information refer to Citrix Blog.

5. Clear the Layer 2 Mode option.
   Note: Select this mode if servers are connected directly to the appliance or if the appliance is used as a transparent bridge.

6. Select the Use Source IP option.
   Note: Select this mode only if an application requires the source IP address.

7. Clear the Client Keep-Alive option.
   Note: Applications can stop working due to optimization. Select this option only when there are performance issues.

8. Clear the TCP Buffering option.
   Note: If the network does not support Window Scaling and there are performance issues, select this option.

9. Clear the MAC Based Forwarding option.
   Note: If you are using one-arm configuration, then select this option.

10. Select the Use Subnet IP option.
    Note: Always select this option unless specific requirements of the network set up do not require it.

11. Select the Layer 3 Mode (IP Forwarding) option.
    Note: If there are security issues and you want to use the appliance as a firewall, then clear this option.

12. Select the Path MTU Discovery option. This mode helps avoid fragmentation of packets.

13. Clear the Static Route Advertisement option.
    Note: If you are using the dynamic routing feature, select this option.

14. Clear the Direct Route Advertisement option.

15. Clear the Intranet Route Advertisement option.

16. Clear the Ipv6 Static Route Advertisement option.

17. Clear the Ipv6 Direct Route Advertisement option.

18. Clear the Bridge BPDUs option.

19. Clear the Bridge BPDUs option.
    The following is a sample screen shot that displays the recommended settings in the Configure Modes dialog box for a generic implementation of an appliance.

    

Features

Enabling features impacts the performance of the NetScaler appliance. Enable only the features that you want to use.

Global System Settings

To configure the global system settings on an appliance, complete the following procedure:

1. Expand the System node of the Navigation pane on the appliance.

2. Select the Settings node.

3. Click the Change global system settings link on the Settings page, as shown in the following screen shot.

   

4. Select the Window Scaling option.
   Note: Clear the Window Scaling option only if it is not supported by the network.

5. Select the Selective Acknowledgment option.
   Note: Clear this option only if the Window Scaling option is clear.

6. Select the Use Nagle’s algorithm option.
   Note: Select this option to use ICA or for heavy flow of small packets.

7. Select the Enable RNAT TCP Proxy option.
   The following is a sample screen shot that displays the recommended settings in the Configure Global Settings dialog box for a generic implementation of an appliance.

   

HTTP Parameters

To configure the HTTP parameters of an appliance, complete the following procedure:

1. Expand the System node of the Navigation pane on the appliance.

2. Select the Settings node.

3. Click the Change HTTP parameters link on the Settings page, as shown in the following screen shot.

   

4. Select the Version 1 option, as shown in the following screen shot:
   Note: Select the Version 0 option only if the environment has earlier releases of Web browser that do not support Cookie Version 1.

5. Select the Drop invalid HTTP requests option, as shown in the following screen shot.

   

   Ensure that you always select this option. It helps in detecting the invalid HTTP headers.

SNMP Alarms

To configure the recommended settings for Simple Network Management Protocol (SNMP) Alarms on an appliance, complete the following procedure:

1. Expand the System node of the Navigation pane on the appliance.

2. Expand the SNMP node.

3. Select the Alarms node.

4. Select the CPU-USAGE alarm in the SNMP Alarms page and click Open.

5. Configure the following options in the Configure SNMP Alarm dialog box:

   • Type 95 in the Alarm Threshold field.

   • Type 35 in the Normal Threshold field.

   • Select Informational from the Severity list.

   • Select the Enable option, as shown in the following screen shot.

     

6. Click OK.

7. Select the MEMORY alarm and click Open.

8. Configure the following options in the Configure SNMP Alarm dialog box:

   • Type 95 in the Alarm Threshold field.
     Note: If this threshold is reached, then force failover the appliance. If it happens again, then contact Citrix Technical Support.

   • Type 35 in the Normal Threshold field.

   • Select Critical from the Severity list.

   • Select Enabled from the Logging list.

   • Enable the Enable option, as shown in the following screen shot.

     

Network Interfaces

To configure the network interfaces on an appliance, complete the following procedure:

1. Expand the Network node of the Navigation pane on the appliance.

2. Select the Interfaces node.

3. Select the interface not in use and click Disable.
   Repeat this step for each interface that is not in use.

4. Disable High Availability Monitoring on all disabled interfaces and on the enabled interface that does not require High Availability Monitoring. To disable High Availability Monitoring on an interface, complete the following procedure:

   1. Select the interface and click Open.

   2. Select the OFF option for HA Monitoring, as shown in the following screen shot.

      

   3. Click OK.

Best Practices

The following is a list of best practices for a generic implementation of an appliance:

• Disable any feature or option that you are not using on the appliance.

• In NetScaler MPX appliance models, management ports 0/1 and 0/2 are only intended for administration of the appliance.

• In NetScaler 9000, 9010, and 10000 appliances, rear facing management port 0/1 is only intended for administration of the appliance.

• In NetScaler 7000 appliance, ports 1/1 through 1/6 are designed to function as 100 Mbps ports.

Additional Resources

For command reference, refer to Citrix Documentation - Command Reference.