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Overview of Phone-Home Provisioning for a Virtual Chassis


With phone-home provisioning, a phone-home client (PHC) on a device initially provisions the device with a software image and configuration from a central network management data source called the phone-home server (PHS), requiring little or no user intervention at the remote site.

A Virtual Chassis consists of a set of devices interconnected together using ports called Virtual Chassis ports (VCPs). You configure and manage the Virtual Chassis as a single device. Starting with Junos OS Release 20.3R1, we’ve made extensions to the phone-home provisioning process for a standalone device so it can also work on a Virtual Chassis. The PHC on a Virtual Chassis requires extra steps to coordinate and manage bootstrapping the member devices.

The PHS is usually part of a network management system (NMS) that supports phone-home provisioning. Your network administrator enters the intended provisioning data that directs how devices and Virtual Chassis at remote sites should be set up. Your organization might have more than one PHS for redundancy.

You can check Feature Explorer and search for phone-home to see the Virtual Chassis platforms that support phone-home provisioning.

Benefits of Phone-Home Provisioning on a Virtual Chassis

  • Simplifies provisioning by launching the process automatically from the remote site, while securely obtaining bootstrap information from a central management system (the PHS) on your network or in the cloud.

  • Doesn’t require in-depth experience with the Junos OS CLI to coordinate the provisioning of multiple devices that make up a Virtual Chassis.

Overview of the Phone-Home Provisioning Process on a Virtual Chassis

On a Virtual Chassis that supports phone-home provisioning, for the process to work, you must set up the Virtual Chassis according to the requirements outlined in How To Enable Phone-Home Provisioning on a Virtual Chassis.

When the Virtual Chassis initially forms, the PHC process starts up automatically on the Virtual Chassis primary member and takes it from there:

  1. The PHC connects to a PHS.

    The PHC sends a provisioning request to a default redirect server URL,, which redirects the request to an available PHS controlled by your network administrator or NMS. This step is the same as phone-home provisioning on a single device.

  2. The PHS responds to the PHC provisioning request with the bootstrapping information, which includes the intended Virtual Chassis topology, software image, and configuration.
  3. The PHC provisions the Virtual Chassis as specified by the PHS.

    Provisioning includes steps such as:

    • Validate the Virtual Chassis topology.

    • Upgrade the software image sequentially on all of the member devices if needed.

    • Run any pre-configuration or post-configuration staging scripts.

    • Commit a new configuration on the Virtual Chassis.

The PHC sends status notifications to the PHS during the bootstrapping process, so the network administrator can verify the process completes successfully.

The PHC also logs status locally in the system log files on the Virtual Chassis. If needed, you can view log files in the Junos OS CLI, and use Junos OS CLI commands to see Virtual Chassis and VCP connection status.