Switching

• Configuring VLANs—Quick Configuration
• Configuring a Spanning Tree—Quick Configuration
• Configuring IGMP Snooping—Quick Configuration
• Configuring GVRP—Quick Configuration

Configuring VLANs—Quick Configuration

Each VLAN is a collection of network nodes that are grouped together to form separate broadcast domains. On an Ethernet network that is a single LAN, all traffic is forwarded to all nodes on the LAN. On VLANs, frames whose origin and destination are in the same VLAN are forwarded only within the local VLAN. Frames that are not destined for the local VLAN are the only ones forwarded to other broadcast domains. VLANs thus limit the amount of traffic flowing across the entire LAN, reducing the possible number of collisions and packet retransmissions within a VLAN and on the LAN as a whole.

On an Ethernet LAN, all network nodes must be physically connected to the same network. On VLANs, the physical location of the nodes is not important, so you can group network devices in any way that makes sense for your organization, such as by department or business function, by types of network nodes, or even by physical location. Each VLAN is identified by a single IP subnetwork and by standardized IEEE 802.1Q encapsulation.

To access the VLAN:

1. In the J-Web user interface, select Configure>Switching>VLAN.

   The VLAN configuration page displays a list of existing VLANs. If you select a specific VLAN, the specific VLAN details are displayed in the details section.

2. Click one:
   • Add—Creates a VLAN.
   • Edit—Edits an existing VLAN configuration.
   • Delete—Deletes an existing VLAN.

     Note: If you delete a VLAN, the VLAN configuration for all the associated interfaces is also deleted.

   When you are adding or editing a VLAN, enter information as described in Table 71.

3. Click one:
   • OK—Saves the configuration and returns to the main configuration page, then click Commit Options>Commit.
   • Cancel—Cancels your entries and returns to the main configuration page.

Configuring a Spanning Tree—Quick Configuration

Juniper devices provide Layer 2 loop prevention through Spanning Tree Protocol (STP), Rapid Spanning Tree Protocol (RSTP), and Multiple Spanning Tree Protocol (MSTP). You can configure bridge protocols data unit (BPDU) protection on interfaces to prevent them from receiving BPDUs that could result in STP misconfigurations, which could lead to network outages.

You can use the J-Web Quick Configuration to add a spanning tree or to edit or delete an existing spanning tree.

To access the Spanning Tree Quick Configuration:

1. In the J-Web user interface, select Configure>Switching>Spanning Tree.

   The Spanning Tree Configuration page displays a list of existing spanning trees. If you select a specific spanning tree, the specific spanning tree details are displayed in the General and Interfaces tabs.

2. Click one of the following:
   • Add—Creates a spanning tree.
   • Edit—Edits an existing spanning-tree configuration.
   • Delete—Deletes an existing spanning tree.

   When you are adding a spanning tree, select a protocol name:

   • If you select STP, enter information as described in Table 72.
   • If you select RSTP, enter information as described in Table 73.
   • If you select MSTP, enter information as described in Table 74.

   Select the Ports tab to configure the ports associated with this spanning tree. Click one of the following:

   • Add—Creates a new spanning-tree interface configuration.
   • Edit—Modifies an existing spanning-tree interface configuration.
   • Delete—Deletes an existing spanning-tree interface configuration.

   When you are adding or editing a spanning-tree port, enter information as described in Table 75.

3. Click one:
   • Click OK to check your configuration and save it as a candidate configuration, then click Commit Options>Commit.
   • click Cancel to cancel the configuration without saving changes.

Configuring IGMP Snooping—Quick Configuration

IGMP snooping regulates multicast traffic in a switched network. With IGMP snooping enabled, the Juniper device monitors the IGMP transmissions between a host (a network device) and a multicast router, keeping track of the multicast groups and associated member interfaces. The Juniper device uses that information to make intelligent multicast-forwarding decisions and forward traffic to the intended destination interfaces.

You can use the J-Web Quick Configuration to add a new IGMP snooping configuration or to edit or delete an existing configuration.

To access the IGMP Snooping Quick Configuration:

1. In the J-Web user interface, select Configure>Switching>IGMP Snooping.

   The VLAN Configuration page displays a list of existing IGMP snooping configurations.

2. Click one:
   • Add—Creates an IGMP snooping configuration for the VLAN.
   • Edit—Edits an existing IGMP snooping configuration for the VLAN.
   • Delete—Deletes member settings for the interface.

     Note: If you delete a configuration, the VLAN configuration for all the associated interfaces is also deleted.

   • Disable Vlan—Disables IGMP snooping on the selected VLAN.

   When you are adding or editing a VLAN, enter information as described in Table 76.

3. Click one:
   • Click OK to check your configuration and save it as a candidate configuration, then click Commit Options>Commit.
   • Click Cancel to cancel the configuration without saving changes.

Configuring GVRP—Quick Configuration

As a network expands and the number of clients and VLANs increases, VLAN administration becomes complex, and the task of efficiently configuring VLANs on multiple EX Series switches becomes increasingly difficult. To automate VLAN administration, you can enable GARP VLAN Registration Protocol (GVRP) on the network.

GVRP learns VLANs on a particular 802.1Q trunk port, and adds the corresponding trunk interface to the VLAN if the advertised VLAN is preconfigured or existing already on the switch. For example, a VLAN named “sales” is advertised to trunk interface 1 on the GVRP-enabled switch. The switch adds trunk interface 1 to the sales VLAN if the sales VLAN already exists on the switch.

As individual interfaces become active and send requests to join a VLAN, the VLAN configuration is updated and propagated among the switches. Limiting the VLAN configuration to active participants reduces the network overhead. GVRP also provides the benefit of pruning VLANs to limit the scope of broadcast, unknown unicast, and multicast (BUM) traffic to interested network devices only.

You can use the J-Web Quick Configuration to enable or disable GVRP on an interface.

To access the GVRP Quick Configuration:

1. In the J-Web user interface, select Configure>Switching>GVRP.

   The GVRP Configuration page displays a list of interfaces on which GVRP is enabled.

2. Click one:
   • Global Settings—Modifies GVRP timers. Enter the information as described in Table 77.
   • Add—Enables GVRP on an interface.
   • Disable Port—Disables an interface.
   • Delete—Deletes an interface.
3. Click one:
   • Click OK to check your configuration and save it as a candidate configuration, then click Commit Options>Commit.
   • Click Cancel to cancel the configuration without saving changes.