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Building and Running Topologies

Junosphere is a cloud-based, virtualization environment in which multiple virtual machines representing network devices can be connected and configured to create network topologies. A topology file set defines the properties necessary to build your network in the cloud.

There are three ways to build or use topologies:

  • Using the Topology Wizard to create a new topology
  • Using existing topologies supplied in the public libraries in Junosphere
  • Using vmm scripting to create a new topology or modify an existing topology

Each of these methods produces a file set that includes a topology.vmm file that defines the virtual devices, such as routers, virtual distributed Ethernet (VDEs), and related connections between the devices within a single topology. The file set can also contain a configuration file for each Junos OS virtual network that is defined in the topology.vmm file.

To use the Topology Wizard to design your topology, refer to the Junosphere Network Topology Guide for more information about how to create and use the topologies.

Note: When creating a topology, the maximum transmission unit (MTU) in the VJX interface must be set to 1500. Otherwise, it cannot route BGP packets.

To start a topology:

  1. Create a reservation for the number of virtual machine units and the number of days needed. The topology cannot be started until the reservation is active. If an annual plan exists and there is sufficient capacity, you do not need a reservation. If the capacity available under the annual plan is insufficient, however, you will need to create a reservation just for the amount of capacity needed to cover the shortfall.

    Note: You must have Topology Management permission to start or stop a topology. If you do not see the green Start button when you select a topology, you do not have the Topology Management permission in the sandbox; see Managing Reservations.

  2. Select Topologies > Manage Topologies from the navigation tree.

    Public libraries provided by Juniper Networks provide topology examples available to all Junosphere users. The bank libraries are created and managed by the bank administrator and are available to all users within the bank. The sandbox topologies are created by the sandbox users who have permission to do so and are accessible only within the particular sandbox.

    Figure 1: Starting a Topology

    Starting a Topology
  3. Select the appropriate topology from the Sandbox, Bank, or Public tab. The topology appears in the Preview window at the bottom of the screen.
  4. Click the green Start button.

Once the topology is started, the Access Active Topology window automatically opens. Users do not have to click that task in the navigation tree. The active topology screen is automatically refreshed with any changes.

A series of messages appears in the Messages tab of the Details section, showing the progress of the loading of the virtual machines, as shown in Figure 2.

Figure 2: Active Topology Messages Tab

Active Topology Messages Tab

When the topology is active, the Join button appears and the virtual machines are displayed in the Virtual Machines tab.

The Junosphere topology parser can detect errors in the topology file. If there is an error in the topology, the error message appears as soon as the you click Start and the topology will not start. Review the topology file for errors and correct them.

When you log out of Junosphere, or the portal times out due to inactivity, the active topologies remain active. You can log out of Junosphere and work directly on your virtual machines using the command-line interface (CLI) via a telnet or SSH session, web-based J-Web interface, or by establishing remote access to the CentOS server. The timeout is a security feature.

If a topology is already active, click Join to launch the Network Connect software to add your host to that topology. See Joining an Active Topology.

To stop an active topology, click Stop in the Active Topology window. The active topology screen is automatically refreshed with any changes.

Published: 2013-08-15