Drift and Reconcile

The drift and reconcile feature helps you identify device drift and reconcile out-of-sync device configuration.

EFA provides APIs to initiate drift and reconcile requests. Drift and reconcile support is provided at the device level. The unit of comparison is a single device whose configuration is compared with EFA and reconciled in case of a drift in the configuration.

Drift and reconcile is used during the following operations:

Switch replacement
After the reboot of a device in maintenance mode

Drift and Reconciliation Engine

The APIs for Drift and Reconcile perform the following operations:

Note

If maintenance-mode-enable-on-reboot is not set on the devices, Data Consistency is not guaranteed and Drift And Reconciliation operation is skipped.

If both maint-mode-enable and maintenance-mode-enable-on-reboot are set on the devices, the Drift and Reconciliation operation is skipped.

Raslog received from the switch starts the state engine for reconciliation of the device.
1. Initiate reconciliation of the Fabric Service
2. Initiate reconciliation of the Tenant Service
Identify the drift in configuration by comparing the fabric configurations in Fabric Service with configurations in Asset service. Fabric service performs reconciliation and pushes the intended configuration from fabric to the device.
Identify the drift in configuration by comparing the Tenant configurations in Tenant Service with configurations in Asset service. Tenant service performs reconciliation and pushes the intended configuration from fabric to the device.

The reconcile API/CLI performs drift-only operation by default that only identifies the configuration drift and displays the information. The reconcile operation, if required has to be specified explicitly. The device discovery is performed as part of the drift reconcile operations.

To improve performance, the drift computation is done in multiple go-routines and bulk switch configurations per device as applicable.