Dell SMA 200 Administration Manual page 197

6 Select Enable Failover to enable probing, monitoring, and failover features.
NOTE: It is important to ensure that the same member receives all cookies to keep the user
authenticated. However, for improved performance in certain situations, all backend
members might be able to accept the session cookies of all users. In this case, the
administrator can decide to turn off Session persistence. The Load Balancer then strictly
adheres to the LB method and LB factors in distributing the load.
7 To add a new member to the group, see
Configuring Probe Settings
To configure probe settings for this load balancing group in the Probe Settings section of the Portals > Load
Balancing screen:
1 Select a Probe Method from the drop-down list. Options include:
• HTTP/HTTPS GET – The Load Balancer sends a HTTP(S) GET request periodically (based on the
configured Probe interval) to see if the HTTP response status code is not greater than or equal to
500 to ensure there are no Web server errors. This is the most reliable method to determine if a
Web server is alive. This method ignores SSL Certificate warnings while probing.
• TCP Connect – The Load Balancer completes a 3-way TCP handshake periodically to monitor the
health of a backend node.
• ICMP Ping – The Load Balancer sends a simple ICMP Ping request to monitor if a backend node is
alive.
2 In the Deactivate Member after field, enter the number of missed intervals required to fail the node.
The default value is 2.
3 In the Reactivate Member after field, enter the number of successful intervals required to reinstate
the node as functional. The default value is 2.
4 In the Display error page when there is no resource available to fail over text box, enter a custom
message or Web page to display in the event that all of the configured backend nodes have failed. HTML
formatting is allowed in this field.
Adding New Members to a Load Balancing Group
To add members to a new or existing load balancing group:
1 When editing or adding a group from the Portals > Load Balancing page, click Add Member. The Load
Balancing Member screen displays.
2 Enter a Member Name to uniquely identify this member within the Load Balancing Group.
3 Enter a friendly name or description in the Comment field to identify this group by mousing over the
group's page.
Adding New Members to a Load Balancing Group
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Administration Guide