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The simulation phase is when you run the simulation of your topology design. The Simulation perspective provides a set of views that support the simulation phase. By comparison, the design and build activities occur in the Design perspective, which provides a set of views that support the design activity. Some views in the Simulation perspective can also be viewed in the Design perspective.
The main areas of focus within the Simulation perspective are the Simulations view and the Console view. The following figure highlights the Simulations and Console views for a running simulation.
Note | To reset your current perspective to its original configuration when the workbench was first opened, right-click the perspective button and select Reset. |
In Cisco Modeling Labs, the number of nodes you can run is limited by the resources available on the server and the number of licenses available. Currently, the design limit is 1,000 nodes.
To launch a simulation, complete the following steps.
Complete the topology design.
Complete the task of building the nodes and interfaces.
Caution | When you manually make changes to a node configuration and bypass AutoNetkit autogeneration, those changes do not appear in the topology view of the Design perspective or Simulation perspective. For example, if you use the hostname command to change the host name from iosv-1 to Router-1 in the configuration, the node name in the topology view and in other related views remains as iosv-1. |
Open the desired topology.
Note | The topology should be open and visible in the Topology Editor. If you have multiple topologies open in the Topology Editor, simulation will launch for the currently active view. |
The jumphost VM is the default method for accessing the management network of a running simulation. The jumphost node runs in a separate simulation named ~jumphost and has two interfaces, eth0 in the project/user management network and eth1 in the FLAT network.
The purpose of the jumphost is to provide an access point into a simulated network that remains fixed, in that there is a single external IP address or port that the user can access. A user can access the jumphost and then access all the nodes inside the simulation.
A VM: Based on the server VM image type.
A Linux container: A lighter weight form of a jumphost. See Linux Container (LXC) for more information.
The VM implementation is costly in terms of the memory and CPU used when a jumphost is instantiated. However, since it is a full-blown server VM, there is value to it, in that you can install and run any application on it.
An LXC provides a means of accessing a topology rather than having to create a full Linux server VM. All nodes in the network are connected to a hidden OOB management network that uses the first interface on each of the nodes.
The LXC is automatically spun up and provides a jumphost point for access into the network. Connecting to the LXC means you can see the interfaces to the outside world and to the OOB network inside your simulation.
A connection is opened from the Cisco Modeling Labs client to a port on the Cisco Modeling Labs server and is forwarded to the LXC. The LXC, in turn, opens a connection to the Management Interface (Gi0/0) of the VM inside the simulation to the node instance.
When the management network property Private simulation network is set, Cisco Modeling Labs assigns a random port for SSH port access to the LXC. However, you can statically define this by setting an extension on your topology.
To set an extension for your topology, complete the following steps.
Step 1 | Click on the canvas to open the Topology tab in the Properties view. |
Step 2 | Click the Extensions tab. |
Step 3 | Click the Add new extension icon. The Edit Extension dialog box appears. |
Step 4 | Enter the
following values:
|
Step 5 | Click OK to add the new extension. When the LXC starts, it will be bound to the TCP port specified in the new extension. |
On occasions, you may need to start your simulation in phases rather than having all nodes launched at the same time. This functionality is facilitated by the Exclude node from simulation launch check box, which allows you to pick and choose which nodes to start.
To launch a phased simulation, complete the following steps.
Step 1 | With the applicable topology open, click on the canvas and move the selection area over the nodes to be excluded from the running simulation. (Alternatively, you can double-click a specific node, hold down the Shift key, and select the remaining nodes.) The view opens. | ||
Step 2 | In the
Exclude node from simulation
launch
check box.
view, check the
| ||
Step 3 | Save your
topology using
Ctrl-S.
| ||
Step 4 | From the toolbar, click the Build Initial Configurations button to build the node configurations. | ||
Step 5 | From the
toolbar, click the
Launch
Simulation button.
The
simulation launches.
|
In circumstances where you need to run a simulation for a specified time, complete the following steps.
Step 1 | From the toolbar, click the down arrow to the right of the Launch Simulation button. | ||||
Step 2 | Click
Launch Simulation (with time
limit).
The Launch Time-limited Simulation dialog box is displayed. | ||||
Step 3 | Set a time
duration for the simulation by entering details for
Days,
Hours, and
Minutes by
using either the up and down arrows or entering the values directly. Click
OK to apply
your time limit to the simulation.
The
simulation launches.
|
You can extend or reduce the time limit set for a running simulation in the User Workspace Management interface. To do this, complete the following steps.
Step 1 | Log in to the User Workspace Management interface. On the Overview page, information on running simulations is displayed. Move to the applicable simulation under the Session heading. If your simulation is due to expire in ten minutes or less, the simulation name is displayed in red. |
Step 2 | Under the
Options
column, click the down arrow and click
Set expiration.
|
Step 3 | The
Set expiration
for session page is displayed. In the date and time field, enter either a
new expiration date and time, a date only, or a time only for the simulation.
|
Step 4 | Click Set expiration to save the changes. The time limit for the simulation is updated. |
Note | This changes the state of the underlying communication infrastructure, not the interface state of the virtual machine. |
To control the state of an interface, complete the following steps.
Step 1 | Log in to the
User Workspace
Management interface.
| ||
Step 2 | On the Overview page, under Sessions, choose the applicable running session. A list of active virtual machines and interfaces is displayed. | ||
Step 3 | Scroll down to the Interfaces section and choose the applicable virtual machine. | ||
Step 4 | From the
applicable
Options
drop-down list, click
Update admin
state.
| ||
Step 5 | Click
Bring down
to bring down the network interface.
A message
is displayed indicating that the interface has been brought down.
| ||
Step 6 | To bring up the
interface at a later stage, click
Update admin
state again.
The
Bring up page displayed.
| ||
Step 7 | Click
Bring up to bring up the network interface.
A message
is displayed indicating that the interface has been brought up.
|
Cisco Modeling Labs provides the capability for you to connect to your nodes via SSH and Telnet. You can start an SSH session, which connects into the node via the LXC, as described in Linux Container (LXC).
This access method makes use of SSH to the LXC and then Telnet from the LXC to the nodes running inside the simulation. This does not use the console port of the nodes and is more reliable and faster to use.
To connect to a simulation node console, complete the following steps.
Step 1 | To connect to a
console for a specific node, right-click the node in the
Simulations view and choose
.
A new Terminal view opens.
| ||||
Step 2 | To disconnect a
terminal from the simulation, click
Disconnect in
the
Terminal view toolbar or click the
Close icon in
the
Terminal view.
|
To connect to all consoles for all nodes in a running simulation, complete the following steps.
Step 1 | Right-click the
simulation in the
Simulations view and choose
.
A new Terminal view opens for all console ports.
| ||||
Step 2 | To disconnect a
terminal from the simulation, click
Disconnect in
the
Terminal view toolbar or click the
Close icon in
the
Terminal view.
|
A terminal multiplexer is available for use with the Cisco Modeling Labs client. It permits a number of terminals to be accessed and controlled from a single terminal. Terminals can be detached to run in the background and then reattached later.
The terminal multiplexer is available from
.
To start a single node, complete the following steps.
Step 1 | Right-click a stopped node. When a node is stopped, its status is shown as [ABSENT]. | ||
Step 2 | Click
Start this node.
| ||
Step 3 | Choose one or more
of the following actions:
|
In cases where a phased simulation is running, you can later start those nodes not started with the initial simulation. To start a node in a running simulation, complete the following steps.
Step 1 | In the
Simulations view, right-click the node.
| ||
Step 2 | Click
Start this
node.
The Requesting start dialog box appears.
|
In cases where a phased simulation is running, you can later start those nodes not started with the initial simulation. To start multiple nodes, complete the following steps.
Step 1 | In the Simulations view, click the first node in the list to be started. | ||
Step 2 | Hold down the Shift key and select the remaining nodes. | ||
Step 3 | Right-click the selected nodes. | ||
Step 4 | Click
Start nodes.
The Requesting start dialog box appears.
|
There are several ways to stop a simulation. In addition, you can stop multiple simulations at the same time. These are discussed in the following sections.
To stop a simulation from the toolbar, complete the following steps.
Step 1 | In the toolbar,
click the
Stop
Simulations button.
A
Stop
Simulation(s) dialog box appears.
| ||
Step 2 | In the Simulation column, click once to highlight the simulation to stop. | ||
Step 3 | (Optional) To
save the configurations, click the adjacent setting in the
Extract
Configurations? column until the prompt changes to
Yes.
| ||
Step 4 | (Optional) To
close the internal terminals associated with the simulation, click the adjacent
setting in the
Close
Terminals? column until the prompt changes to
Yes.
| ||
Step 5 | To stop the simulation, click the adjacent setting in the Stop Simulation? column until the prompt changes to Yes. | ||
Step 6 | Click
OK to stop the
simulation, or click
Cancel to leave
the simulation running.
On OS X, you update the values for Extract Configurations?, Stop Simulation?, and Close Terminals? in the columns directly. You do not need to select the name of the simulation. |
To stop a simulation, complete the following steps.
Step 1 | In the
Simulations view, right-click the simulation name and
select
Stop
Simulation.
The Stop Simulation Confirmation dialog box appears.
| ||
Step 2 | Click
OK to stop the
simulation.
Once
selected, all nodes in the simulation start shutting down. It may take a few
minutes for the simulation to shut down completely and to disappear from the
Simulations view.
|
To stop multiple simulations, complete the following steps.
Step 1 | In the Simulations view, click the first simulation in the list to stop. | ||
Step 2 | Hold down the Shift key and select the remaining simulations. | ||
Step 3 | Right-click the
selected simulations and select
Stop
Simulations.
The Stop Simulations Confirmation dialog box appears.
| ||
Step 4 | Click
OK to stop the
simulations.
Once
selected, all nodes in the simulations start shutting down. It may take a few
minutes for the simulations to shut down completely and to disappear from the
Simulations view.
|
To stop a single node in a simulation, complete the following steps.
Step 1 | In the
Simulations view, right-click the node to stop and
select
Stop this Node.
The Are you sure? dialog box appears. | ||
Step 2 | Click
OK to stop the
node. Alternatively, click
Cancel to abandon
the operation and return to the simulation.
|
To stop multiple nodes in a running simulation, complete the following steps.
Step 1 | In the Simulations view, click the first node in the list to stop. | ||
Step 2 | Hold down the Shift key and select the remaining nodes. | ||
Step 3 | Right-click the selected nodes. | ||
Step 4 | Click
Stop Nodes.
The Are you sure? dialog box appears. | ||
Step 5 | Click
OK to stop the
nodes. Alternatively, click
Cancel to
abandon the operation and return to the simulation.
|
To modify a node configuration in a running simulation via SSH, complete the following steps.
Step 1 | Right-click the
node in the
Simulations view and choose
SSH > to its
Management (via LXC) port.
A new Terminal view opens.
| ||
Step 2 | If no banner or router prompt is visible, press Enter. You are now working with the operating system running on the node, for example, Cisco IOSv virtual software. | ||
Step 3 | Use the
operating system commands to view or modify the node configuration.
|
To modify a node configuration in a running simulation via Telnet, complete the following steps.
Step 1 | Right-click the
node in the
Simulations view and choose
Telnet > to
its Console port.
A new Terminal view opens.
| ||
Step 2 | If no banner or router prompt is visible, press Enter. You are now working with the operating system running on the node, for example, Cisco IOSv virtual software. | ||
Step 3 | Use the
operating system commands to view or modify the node configuration.
|
To modify multiple node configurations in a running simulation, complete the following steps.
Step 1 | Right-click the
topology in the
Simulations view and choose
Telnet > to
all <number> available Console ports.
| ||
Step 2 | If no banner or router prompt is visible, press Enter. You are now working with the operating system running on the node, for example, Cisco IOSv virtual software. | ||
Step 3 | Use the
operating system commands to view or modify the node configuration.
|
To extract and save modified configurations, complete the following steps.
Step 1 | In the
Simulations view, right-click the topology name,
making sure not to click the node name, and select
Extract
Configurations.
| ||
Step 2 | Ensure that all
external Telnet connections to the simulation are closed before proceeding.
| ||
Step 3 | Click
OK.
The Extracting Configurations dialog box appears indication that the extraction is in process. When the extraction is complete, a message is displayed.
| ||
Step 4 | Click OK. |
During a configuration extraction, if the process encounters issues or fails for a particular node, the problem node is identified and reported.
The extraction process then continues for all other nodes in the simulation and returns collected configurations to you.
When a Linux server is present in a running simulation, you can use the User Workspace Management interface to take a snapshot of the disk content of the server. This newly created user-specific disk image can be used in other simulated sessions.
To take a snapshot of the server's disk contents, complete the following steps.Step 1 | Log in to the
User Workspace Management interface.
| ||
Step 2 | On the
Overview page, under
Sessions,
select the applicable running simulation.
| ||
Step 3 | Select the
applicable Linux server, and from the
Options
drop-down menu, click
Create
snapshot.
Project details for the newly created snapshot are displayed. |
To reuse the image snapshot, complete the following steps.
Step 1 | Create a new topology or open an existing topology. |
Step 2 | On the canvas, add a node to the topology. |
Step 3 | Select the node on the canvas. The sample topology opens in the Topology Editor canvas. |
Step 4 | In the The Select VM Image dialog box appears. view, click Browse beside the VM Image field. |
Step 5 | Select the
applicable image snapshot and click
OK.
Details for the image snapshot are visible in the VM Image field under view. |