NSO does not just fire-off commands to the network, but rather confirms that all changes in the transaction are deployed correctly at the device level. If at any point of the series a device cannot be changed, the entire transaction is automatically roll-backed. This ensures that there is always a consistent network state. Complex rollback-scenarios like correct ordering of CLI commands is handled. The NSO database, the services and the devices configurations are all part of the same transaction.
Users can load network-wide rollback files to undo network changes.