F5 Lab 1.12: High Availability - Active/Active Configuration

As I mention on my last article here about high available options, F5 supports active/standby or active/active mode for handling the traffic. Active/active on the F5 is based on traffic-group perspective. Traffic-group is a "container" of failover objects, it contains self IPs, virtual server, virtual address and so on. On active/active pair of F5 both F5 will act as active for one-or more traffic-group but at the same time it also as standby for the other. So it's different from active/standby mode which only one F5 act as an active device for all traffic-groups and the other one only standby mode.

On my lab, I have scenario for creating two traffic-groups, traffic-group1 will be used for transactional application and traffic-group2 will used for non-transactional application.

• Traffic-group1: Active on F5-HA1 and Standby on F5-HA2
• Traffic-group2: Active on F5-HA2 and Standby on F5-HA1

Here below the diagram of each traffic-group:

• Traffic-group 1: Transactional Application

• Traffic-group 2: Non-Transactional Application

Let's lab the scenario:

1. Verify existing traffic-groups and the objects. On GUI, navigate to Device Management => Traffic Groups

• Traffic Groups Status

From the capture status, on traffic-group-1 bigip1 is currently active device and the bigip2 is on standby. If the system failover, bigip2 will be the active.

• Traffic Groups Object

To view failover objects, click on traffic-group-1 and go to Failover Object tab.

Based on the capture, there are 4 objects existed on the traffic group. It consists of two floating IPs and two virtual addresses. Both virtual-addresses is used on virtual servers below:

As the diagram above, transactional application will remains on traffic-group-1 but the non-transactional will be moved to traffic-group-2. So I will move the floating self IP for WEB_VLAN_2_FLOAT and virtual address for MARKETING_WEB to traffic-group-2.

2. Create new traffic-group. Navigate to Device Management => Traffic Groups. Then click "Create"

3. On the traffic-group creation page, it will need configure some parameters

• Name: Name of configured traffic-group
• Description: Traffic group description for identification
• MAC Masquerade Address: Floating MAC Address of the traffic group. For best practice it should be configured to an address which will minimize failover downtime so when failover, ARP learning process will simplified. For this time, I will not used it.
• HA Group: Assign HA Group health monitor for failover trigger. It will be used on HA Score failover method
• Failover Method: How failover will occur, it will based on HA Score or Preferred Device Order and then Load Aware. I will cover it later on different lab.
• Failover Order: This option will available when choosing Preferred Device Oder and then Load Aware method.
• HA Load Factor: Value that represents the application load for this traffic group relative to other active traffic groups on the local device.

Then click "Create Traffic Group".

4. After it created, let's change the traffic group for WEB_VLAN_2_FLOAT and virtual address for MARKETING_WEB to traffic-group-2.

5. Let's make F5-HA2 to be active device for non-transactional-traffic-group-2.

To make F5-HA2 as active device for non-transactional-traffic-group-2, we should force the bigip1 to standby by selecting the traffic group and then force to standby.

Verify the active device for each traffic-groups:

As we can see from the output, the active device for non-transactional-traffic-group-2 is bigip2.

6. Let's verify from traffic perspective by accessing each virtual server on each traffic group.

• Accessing MARKETING_WEB:

When accessing the MARKETING_WEB VS, the connection table only shows on bigip-2. It proves that bigip-2 is processing the traffic for MARKETING_WEB VS.

• Accessing PAYMENT_WEB:

When accessing the PAYMENT_WEB VS, the connection table only shows on bigip-1. It proves that bigip-1 is processing the traffic for PAYMENT_WEB VS.

Based on the test result, it shows that Active/Active high availability scenario is successfully implemented.

Reference:

• F5-Active/Active
• F5-Failover