Traffic Manager Failover

When each Traffic Manager in a cluster determines that one of its peers has failed, the Traffic Manager may take over some or all of the traffic shares for which that failed system was responsible.

Each Traffic Manager in a cluster uses its knowledge of which machines are active to determine which Traffic IPs it should be using. The cluster uses a fully deterministic algorithm to determine which Traffic Manager should host the traffic IP address. Because the algorithm is deterministic, the Traffic Managers do not need to negotiate when one of their peers fails or recovers.

When a failed Traffic Manager recovers, it announces that it is able to host a Traffic IP address again but does not automatically take over the address, even if it was hosting it when it failed. Instead, message displays indicating that the Traffic Manager has recovered and can take back the Traffic IP addresses. To reactivate the Traffic Manager, go to the Diagnose page and click the Reactivate this Traffic Manager link.

This behavior exists because each time traffic shares are transferred from one Traffic Manager to another, any connections currently in that share are dropped. Dropped connections are inevitable when a transfer occurs because a Traffic Manager fails, but might not be desirable when a Traffic Manager recovers.

If you would prefer recovering Traffic Manager to take back the Traffic IP addresses automatically, enable the flipper!autofailback setting on the System > Fault Tolerance page.