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Viptela Documentation

VPN Interface Bridge

Use the VPN-Interface-Bridge template for all vEdge Cloud and vEdge router devices.

Integrated routing and bridging (IRB) allows vEdge routers in different bridge domains to communicate with each other. To enable IRB, create logical IRB interfaces to connect a bridge domain to a VPN. The VPN provides the Layer 3 routing services necessary so that traffic can be exchanged between different VLANs. Each bridge domain can have a single IRB interface and can connect to a single VPN, and a single VPN can connect to multiple bridge domains on a vEdge router.

To configure a bridge interface using vManage templates:

  1. Create a VPN-Interface-Bridge feature template to configure parameters for logical IRB interfaces, as described in this article.
  2. Create a Bridge feature template for each bridging domain, to configure the bridging domain parameters. See the Bridge help topic.

Navigate to the Template Screen and Name the Template

  1. In vManage NMS, select the Configuration ► Templates screen.
  2. In the Device tab, click Create Template.
  3. From the Create Template drop-down, select From Feature Template.
  4. From the Device Model drop-down, select the type of device for which you are creating the template.
  5. Click the Service VPN tab located directly beneath the Description field, or scroll to the Service VPN section.
  6. Click the Service VPN drop-down.
  7. Under Additional VPN Templates, located to the right of the screen, click VPN Interface Bridge.
  8. From the VPN Interface Bridge drop-down, click Create Template. The VPN-Interface-Bridge template form is displayed. The top of the form contains fields for naming the template, and the bottom contains fields for defining VPN Interface Bridge parameters.
  9. In the Template Name field, enter a name for the template. The name can be up to 128 characters and can contain only alphanumeric characters.
  10. In the Template Description field, enter a description of the template. The description can be up to 2048 characters and can contain only alphanumeric characters.

When you first open a feature template, for each parameter that has a default value, the scope is set to Default (indicated by a check mark), and the default setting or value is shown. To change the default or to enter a value, click the scope drop-down to the left of the parameter field and select one of the following:

Parameter Scope

Scope Description

Device Specific (indicated by a host icon)

Use a device-specific value for the parameter. For device-specific parameters, you cannot enter a value in the feature template. You enter the value when you attach a Viptela device to a device template.

When you click Device Specific, the Enter Key box opens. This box displays a key, which is a unique string that identifies the parameter in a CSV file that you create. This file is an Excel spreadsheet that contains one column for each key. The header row contains the key names (one key per column), and each row after that corresponds to a device and defines the values of the keys for that device. You upload the CSV file when you attach a Viptela device to a device template. For more information, see Create a Template Variables Spreadsheet.

To change the default key, type a new string and move the cursor out of the Enter Key box.

Examples of device-specific parameters are system IP address, hostname, GPS location, and site ID.

Global (indicated by a globe icon)

Enter a value for the parameter, and apply that value to all devices.

Examples of parameters that you might apply globally to a group of devices are DNS server, syslog server, and interface MTUs.

Create a Bridging Interface

To configure an interface to use for bridging servers, select the Basic Configuration tab and click configure the following parameters. Parameters marked with an asterisk are required to configure bridging.

Parameter Name Description
Shutdown* Click No to enable the interface.
Interface name* Enter the name of the interface, in the format irbnumber. The IRB interface number can be from 1 through 63, and must be the same as the VPN identifier configured in the Bridge feature template for the bridging domain that the IRB is connected to.
Description Enter a description for the interface.
IPv4 Address* Enter the IPv4 address of the router.
DHCP Helper

Enter up to eight IP addresses for DHCP servers in the network, separated by commas, to have the interface be a DHCP helper. A DHCP helper interface forwards BOOTP (Broadcast) DHCP requests that it receives from the specified DHCP servers.

Block Non-Source IP Click Yes to have the interface forward traffic only if the source IP address of the traffic matches the interface's IP prefix range.
Secondary IP Address (on vEdge routers) Click Add to configure up to four secondary IPv4 addresses for a service-side interface.

To save the template, click Save.

CLI equivalent:

vpn vpn-id
  interface irbnumber
    description "text description"
    dhcp-helper ip-addresses
    ip address prefix/length   
    mac-address mac-address    
    mtu bytes
    secondary-address ipv4-address
    [no] shutdown
    tcp-mss-adjust bytes

Apply Access Lists

To apply access lists to IRB interfaces, select the ACL tab and configure the following parameters:

Parameter Name Description
Ingress ACL – IPv4

Click On, and specify the name of an IPv4 access list to packets being received on the interface.

Egress ACL– IPv4 Click On, and specify the name of an IPv4 access list to packets being transmitted on the interface.

To save the feature template, click Save.

CLI equivalent:

vpn vpn-id
  interface irbnumber
    access-list acl-name (in | out)

Configure VRRP

To have an interface run the Virtual Router Redundancy Protocol (VRRP), which allows multiple routers to share a common virtual IP address for default gateway redundancy, select the VRRP tab. Then click Add New VRRP and configure the following parameters:

Parameter Name Description
Group ID

Enter the virtual router ID, which is a numeric identifier of the virtual router.
Range: 1 through 255


Enter the priority level of the router. There router with the highest priority is elected as master. If two vEdge routers have the same priority, the one with the higher IP address is elected as master.
Range: 1 through 254
Default: 100


Specify how often the VRRP master sends VRRP advertisement messages. If slave routers miss three consecutive VRRP advertisements, they elect a new master.
Range: 1 through 3600 seconds
Default: 1 second

Track OMP
​Track Prefix List

By default, VRRP uses of the state of the service (LAN) interface on which it is running to determine which vEdge router is the master virtual router. if a vEdge router loses all its WAN control connections, the LAN interface still indicates that it is up even though the router is functionally unable to participate in VRRP. To take WAN side connectivity into account for VRRP, configure one of the following:

Track OMP—Click On for VRRP to track the Overlay Management Protocol (OMP) session running on the WAN connection. If the master VRRP router loses all its OMP sessions, VRRP elects a new default gateway from those that have at least one active OMP session.

Track Prefix List—Track both the OMP session and a list of remote prefixes, which is defined in a prefix list configured on the local router. If the master VRRP router loses all its OMP sessions, VRRP failover occurs as described for the Track OMP option. In addition, if reachability to one of the prefixes in the list is lost, VRRP failover occurs immediately, without waiting for the OMP hold timer to expire, thus minimizing the amount of overlay traffic is dropped while the vEdge routers determine the VRRP master.

IP Address Enter the IP address of the virtual router. This address must be different from the configured interface IP addresses of both the local vEdge router and the peer running VRRP.

To save the VRRP configuration, click Add.

To save the feature template, click Save.

CLI equivalent:

vpn vpn-id
  interface irbnumber[.subinterface]
    vrrp group-number
      ipv4 ip-address    
      priority number
      timer seconds
      (track-omp | track-prefix-list list-name)

Add ARP Table Entries

To configure static Address Resolution Protocol (ARP) table entries on the interface, select the ARP tab. Then click Add New ARP and configure the following parameters:

Parameter Name Description
IP Address Enter the IP address for the ARP entry in dotted decimal notation or as a fully qualified host name.
MAC Address Enter the MAC address in colon-separated hexadecimal notation.

To save the ARP configuration, click Add.

To save the feature template, click Save.

CLI equivalent:

vpn vpn-id
  interface irbnumber
      ip address ip-address mac mac-address

Configure Other Interface Properties

To configure other interface properties, select the Advanced tab and configure the following parameters:

Parameter Name Description
MAC Address Specify a MAC address to associate with the interface, in colon-separated hexadecimal notation.
IP MTU Specify the maximum MTU size of packets on the interface.
Range: 576 through 1804
Default: 1500 bytes
TCP MSS Specify the maximum segment size (MSS) of TPC SYN packets passing through the vEdge router. By default, the MSS is dynamically adjusted based on the interface or tunnel MTU such that TCP SYN packets are never fragmented.
Range: 552 to 1460 bytes
Default: None

Click On to clear the Don't Fragment (DF) bit in the IPv4 packet header for packets being transmitted out the interface. When the DF bit is cleared, packets larger than that interface's MTU are fragmented before being sent.

ARP Timeout

Specify how long it takes for a dynamically learned ARP entry to time out.

Range: 0 through 2678400 seconds (744 hours)
Default: 1200 seconds (20 minutes)

To save the feature template, click Save.

CLI equivalent:

vpn vpn-id
  interface irbnumber
    arp-timeout seconds
    mac-address mac-address    
    mtu bytes 
    tcp-mss-adjust bytes

Release Information

Introduced in vManage NMS in Release 15.3.

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