Netgear XCM8810 Chassis User Manual - Page 67

NETGEAR 8800 User Manual Relaying Configuration Information To facilitate a failover from the primary node to the backup node, the primary transfers its active configuration to the backup. Relaying configuration information is the first level of checkpointing. During the initial switch boot-up, the primary's configuration takes effect. During the initialization of a node, its configuration is read from the local flash. After the primary and backup nodes have been elected, the primary transfers its current active configuration to the backup. After the primary and backup nodes are synchronized, any configuration change you make to the primary is relayed to the backup and incorporated into the backup's configuration copy. Note: To ensure that all of the configuration commands in the backup's flash are updated, issue the save command after you make any changes. If a failover occurs, the backup node continues to use the primary's active configuration. If the backup determines that it does not have the primary's active configuration because a run-time synchronization did not happen, the switch reboots. Because the backup always uses the primary's active configuration, the active configuration remains in effect regardless of the number of failovers. Note: If you issue the reboot command before you save your configuration changes, the switch prompts you to save your changes. To keep your configuration changes, save them before you reboot the switch. Bulk Checkpointing Bulk checkpointing causes the primary and backup run-time states to be synchronized. Since XCM8800 runs a series of applications, an application starts checkpointing only after all of the applications it depends on have transferred their run-time states to the backup MSM/MM node. After one application completes bulk checkpointing, the next application proceeds with its bulk checkpointing. To monitor the checkpointing status, use the show checkpoint-data {} command. To see if bulk checkpointing is complete, that is, to see if the backup node is fully synchronized (In Sync) with the primary node, use the show switch {detail} command. If a failover occurs before bulk checkpointing is complete, the switch reboots. However, once bulk checkpointing is complete, failover is possible without a switch reboot. Chapter 3. Managing the Switch | 67