Knowledge Base

Split-brain Avoidance can be configured during the installation of VMware vCenter Server Heartbeat via the Configure Server wizard or post installation via the VMware vCenter Server Heartbeat Console. Split-brain Avoidance is used in WAN installations to ensure that only one server becomes active if the channel connection is lost, but both servers are still connected to the corporate (public) network. Split-brain Avoidance works by pinging from the passive server to the active server across the corporate (public) network. If the active server responds, the passive does not failover, even if the VMware Channel connection is lost. This feature requires that the active and passive servers have different IP addresses on the corporate (public) network, which is typically the case for WAN installations.

Configure Server Wizard

To enable this feature, Click the Network Monitoring tab of the Configure Server wizard and enable Split brain avoidance (Recommended for WAN) option. Enter the principal (public) IP address used by each server. You also need to configure auxiliary IP addresses on both principal (public) network cards. This is required to allow the passive server to send a ping. To configure auxiliary IP address on the principal (public) network cards, follow the procedure below.

Auxiliary IP addresses are additional IP addresses that are assigned to the network card, which is connected to the corporate (public) network. They are used to allow the passive server to communicate, because unlike the principal (public) network address, they are not filtered. This allows the passive server to send pings, and is also required to allow the passive server to send email alerts.

To configure an auxiliary IP address:

1. Open the network properties for the principal (public) network connection.
2. Double-click TCP/IP to display the properties.
3. Click Advanced.
4. Enter an additional (currently unused) IP address in the table.
5. Reposition the IP addresses in the list so that the additional (auxiliary) IP address appears first, and the principal (public) network address, by which clients connect to the server, appears second.
6. Click OK on all three dialogs to accept the configuration changes to the network connection.
7. After completing all of the steps, click Next or Finish.

vCenter Server Heartbeat Console

To configure Split-Brain Avoidance using the vCenter Server Heartbeat Console:

1. Open the vCenter Server Heartbeat Console.
2. Click Advanced > Communication.
3. Click the Split-Brain Avoidance Configuration tab.
4. Enable Split-Brain Avoidance.
5. Configure the Ping Interval and Timeout for Ping Echoes fields.
6. Enter the IP addresses for both the Primary and Secondary server principal (public) NICs.
7. Click Apply.