Boot sequence

After you install an OPX image, the system automatically loads the image and boots.

1. After the switch powers up or reboots, the boot menu displays. After a short delay, the system auto boots by loading the image — in this case OPX-A partition. If required, during the delay you can interrupt the auto boot and select other options to select OPX-B to load another software image, or go back to ONIE for upgrades, system recovery, and so on.

+--------------------------------------------------------+
| *OPX-A                                                 |
| OPX-B                                                  |
| ONIE                                                   |
+--------------------------------------------------------+

2. Linux boots from the OPX-A partition on the disk and starts the systemd daemon in the root file system as part of the initial setup before the Linux login displays.

The systemd daemon starts custom services during initialization:

• PAS service initializes the platform and devices on the system
• NAS service initializes the NPU and system interfaces
• Other OPX services create Linux interfaces that map to physical, front-panel ports on the switch

After OPX custom services run successfully and the system boots up, the Linux prompt displays on the console for you to log in.

NOTE: If the service that creates internal Linux interfaces is unsuccessful, the system bootup waits 300 seconds before timing out and displays the Linux login prompt. Log into OPX and use the troubleshooting steps to determine the cause of the failure. You can use systemctl to determine if any services have failed, and journalctl to inspect the log contents.