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Examples: Configuring Logical System Interfaces

Understanding Interfaces

Interfaces act as a doorway through which traffic enters and exits a device. Juniper Networks devices support a variety of interface types:

  • Network interfaces—Networking interfaces primarily provide traffic connectivity.
  • Services interfaces—Services interfaces manipulate traffic before it is delivered to its destination.
  • Special interfaces—Special interfaces include management interfaces, the loopback interface, and the discard interface.

Each type of interface uses a particular medium to transmit data. The physical wires and Data Link Layer protocols used by a medium determine how traffic is sent. To configure and monitor interfaces, you need to understand their media characteristics, as well as physical and logical properties such as IP addressing, link-layer protocols, and link encapsulation.

Note: Most interfaces are configurable, but some internally generated interfaces are not configurable.

Example: Creating an Interface on a Logical System

This example shows how to create an interface on a logical system.

Requirements

For the interface on the logical system to have connectivity, the corresponding physical interface must be administratively up, and the physical link must be up. You can verify the status of the physical interface by running the show interfaces terse command.

Overview

In logical systems, you must treat each interface like a point-to-point connection because you can only connect one logical tunnel interface to another at any given time. Also, you must select an interface encapsulation type, specify a DLCI number or VLAN identifier, configure a corresponding protocol family, and set the logical interface unit number of the peering lt interface.

To configure the interface encapsulation type, include the dlci, encapsulation, family, peer-unit, and vlan-id statements at the following hierarchy levels:

  • M Series, MX Series, or T Series router (master administrator only)—[edit interfaces lt-fpc/pic/0 unit unit-number]
  • Logical system—[edit logical-systems logical-system-name interfaces lt-fpc/pic/0 unit unit-number]
    [edit]
    logical-systems logical-system-name {interfaces {lt-fpc/pic/0 {unit unit-number {encapsulation (ethernet | ethernet-ccc | ethernet-vpls | frame-relay | frame-relay-ccc | vlan | vlan-ccc | vlan-vpls);peer-unit number; # The logical unit number of the peering lt interface.dlci dlci-number; vlan-id vlan-number;family (ccc | inet | inet6 | iso | mpls | tcc);}}}}

    Note: When you configure IPv6 addresses on a logical tunnel interface, you must configure unique IPv6 link-local addresses for any logical interfaces that peer with one another. To configure a link-local address, you must be the master administrator. Include a second IPv6 address with the address statement at the [edit interfaces lt-fpc/pic/port unit unit-number family inet6] hierarchy level. Link-local addresses typically begin with the numbers fe80 (such as fe80::1111:1/64).

In this example, you create the fe-1/1/3 physical interface on the main router. You can also add values for properties that you need to configure on the physical interface, such as physical encapsulation, VLAN tagging (enabling), and link speed.

The example then shows how to assign logical interfaces to a logical system. Once you do this, the logical interfaces are considered part of the logical system.

Any logical interface unit can only be assigned to one system, including the main router. For example, if you configure logical unit 3 in the main router, you cannot configure logical unit 3 in a logical system.

In this example, you create logical unit 0 on Logical System LS1. You can also add values for properties that you need to configure on the logical interface, such as logical interface encapsulation, VLAN ID number, and protocol family.

Configuration

CLI Quick Configuration

To quickly configure this example, copy the following commands, paste them into a text file, remove any line breaks, change any details necessary to match your network configuration, and then copy and paste the commands into the CLI at the [edit] hierarchy level.

set interfaces fe-1/1/3 description "main router interface"set logical-systems LS1 interfaces fe-1/1/3 unit 0 description "LS1 interface"set logical-systems LS1 interfaces fe-1/1/3 unit 0 family inet address 10.11.2.2/24

Step-by-Step Procedure

The following example requires you to navigate various levels in the configuration hierarchy. For information about navigating the CLI, see Using the CLI Editor in Configuration Mode in the CLI User Guide.

To configure an interface on a logical system:

  1. As the master administrator, configure the physical interface on the main router.

    [edit]user@host# set interfaces fe-1/1/3 description "main router interface"

  2. Create the logical system interface on the logical unit.

    [edit]user@host# set logical-systems LS1 interfaces fe-1/1/3 unit 0 description "LS1 interface" user@host# set logical-systems LS1 interfaces fe-1/1/3 unit 0 family inet address 10.11.2.2/24

  3. If you are done configuring the device, commit the configuration.

    [edit]user@host# commit

Verification

To verify that the configuration is working properly, issue the show interfaces command.

Example: Connecting a Logical System to a Physical Router

This example shows how to configure an interface on a logical system to connect to a separate router. The separate router can be a physical router or a logical system on a physical router.

Requirements

PICs must be installed on the two routers.

Overview

In this example, Logical System LS1 is configured on Router R1. The Logical System LS1 has a direct connection to Router R2.

Figure 1 shows the topology used in this example.

Figure 1: Logical System Connected to a Physical Router

Logical System Connected to a Physical Router

Configuration

CLI Quick Configuration

To quickly configure this example, copy the following commands, paste them into a text file, remove any line breaks, change any details necessary to match your network configuration, and then copy and paste the commands into the CLI at the [edit] hierarchy level.

Router R1

set interfaces so-0/0/2 description "main router interface to R2"set logical-systems LS1 interfaces so-0/0/2 unit 0 description LS1->R2set logical-systems LS1 interfaces so-0/0/2 unit 0 family inet address 10.0.45.2/30

Device R2

set interfaces so-0/0/2 description R2->LS1set interfaces so-0/0/2 unit 0 family inet address 10.0.45.1/30

Step-by-Step Procedure

The following example requires you to navigate various levels in the configuration hierarchy. For information about navigating the CLI, see Using the CLI Editor in Configuration Mode in the CLI User Guide.

To connect a logical system to a physical router:

  1. On Router R1, configure the interface.

    [edit]user@R1# set interfaces so-0/0/2 description "main router interface to R2"

  2. On Router R1, configure the Logical System LS1 interface.

    [edit]user@R1# set logical-systems LS1 interfaces so-0/0/2 unit 0 description LS1->R2 user@R1# set logical-systems LS1 interfaces so-0/0/2 unit 0 family inet address 10.0.45.2/30

  3. On Device R2, configure the interface to Logical System LS1.

    [edit]user@R2# set interfaces so-0/0/2 description R2->LS1 user@R2# set interfaces so-0/0/2 unit 0 family inet address 10.0.45.1/30

  4. If you are done configuring the devices, commit the configurations.

    [edit]user@host# commit

Verification

Confirm that the configuration is working properly.

Verifying Connectivity

Purpose

Make sure that the devices can ping each other.

Action

user@R2> ping 10.0.45.2
PING 10.0.45.2 (10.0.45.2): 56 data bytes
64 bytes from 10.0.45.2: icmp_seq=0 ttl=64 time=3.910 ms
64 bytes from 10.0.45.2: icmp_seq=1 ttl=64 time=3.559 ms
64 bytes from 10.0.45.2: icmp_seq=2 ttl=64 time=3.503 ms
user@R1> set cli logical-system LS1
Logical system: LS1
user@R1:LS1> ping 10.0.45.1
PING 10.0.45.1 (10.0.45.1): 56 data bytes
64 bytes from 10.0.45.1: icmp_seq=0 ttl=64 time=1.217 ms
64 bytes from 10.0.45.1: icmp_seq=1 ttl=64 time=1.183 ms
64 bytes from 10.0.45.1: icmp_seq=2 ttl=64 time=1.121 ms

Example: Connecting Logical Systems Within the Same Router Using Logical Tunnel Interfaces

This example shows how to configure logical tunnel interfaces to connect two logical systems that are configured in a single router.

Requirements

On M Series and T Series routers, you can create a logical tunnel interface if you have a Tunnel Services PIC installed on an Enhanced FPC in your routing platform.

On M40e routers, you can create a logical tunnel interface if you have a Tunnel Services PIC. (An Enhanced FPC is not required.)

On an M7i router, logical tunnel interfaces can be created by using the integrated Adaptive Services Module.

On an MX Series router, the master administrator can configure logical tunnel interfaces by including the tunnel-services statement at the [edit chassis fpc slot-number pic number] hierarchy level.

Overview

To connect two logical systems, you configure a logical tunnel interface on both logical systems. Then you configure a peer relationship between the logical tunnel interfaces, thus creating a point-to-point connection. Logical tunnel interfaces behave like regular interfaces. You can configure them with Ethernet, Frame Relay, or another encapsulation type. You can also configure routing protocols across them. In effect, the logical tunnel (lt) interfaces connect two logical systems within the same router. The two logical systems do not share routing tables. This means that you can run dynamic routing protocols between different logical systems within the same router.

You must treat each interface like a point-to-point connection because you can only connect one logical tunnel interface to another at any given time. Also, you must select an interface encapsulation type, configure a corresponding protocol family, and set the logical interface unit number of the peering lt interface.

In this example, the logical tunnel interfaces are configured to behave as Ethernet interfaces with the encapsulation ethernet statement. The IS-IS Protocol is enabled on the logical tunnel interfaces with the family iso statement.

When configuring logical tunnel interfaces, note the following:

  • The peering logical interfaces must have the same physical lt interface name. For example, a logical unit on lt-0/1/0 cannot peer with a logical unit on lt-0/0/10. The FPC, PIC, and port numbers must match.
  • The peering logical interfaces must be derived from the same PIC or module.
  • You can configure only one peer unit for each logical interface. For example, unit 0 cannot peer with both unit 1 and unit 2.
  • Logical tunnels are not supported with Adaptive Services, MultiServices, or Link Services PICs, but they are supported on the Adaptive Services Module on M7i routers.

Figure 2 shows the topology used in this example.

Figure 2: Connecting Two Logical Systems

Connecting Two Logical Systems

Configuration

CLI Quick Configuration

To quickly configure this example, copy the following commands, paste them into a text file, remove any line breaks, change any details necessary to match your network configuration, and then copy and paste the commands into the CLI at the [edit] hierarchy level.

set logical-systems LS1 interfaces lt-0/1/0 unit 0 description LS1->LS2 set logical-systems LS1 interfaces lt-0/1/0 unit 0 encapsulation ethernet set logical-systems LS1 interfaces lt-0/1/0 unit 0 peer-unit 1 set logical-systems LS1 interfaces lt-0/1/0 unit 0 family inet address 10.0.8.13/30 set logical-systems LS1 interfaces lt-0/1/0 unit 0 family iso set logical-systems LS2 interfaces lt-0/1/0 unit 1 description LS2->LS1 set logical-systems LS2 interfaces lt-0/1/0 unit 1 encapsulation ethernet set logical-systems LS2 interfaces lt-0/1/0 unit 1 peer-unit 0 set logical-systems LS2 interfaces lt-0/1/0 unit 1 family inet address 10.0.8.14/30 set logical-systems LS2 interfaces lt-0/1/0 unit 1 family iso

Step-by-Step Procedure

The following example requires you to navigate various levels in the configuration hierarchy. For information about navigating the CLI, see Using the CLI Editor in Configuration Mode in the CLI User Guide.

To connect logical system interfaces:

  1. Run the show interfaces terse command to verify that the router has a logical tunnel (lt) interface.
    user@host> show interfaces terse
    Interface               Admin Link Proto    Local                 Remote
so-0/0/0                up    down
so-0/0/1                up    down
so-0/0/2                up    down
so-0/0/3                up    down
gr-0/1/0                up    up  
ip-0/1/0                up    up  
lt-0/1/0                up    up  
...

  2. Configure the logical tunnel interface on Logical System LS1.

    [edit]user@host# set logical-systems LS1 interfaces lt-0/1/0 unit 0 description LS1->LS2 user@host# set logical-systems LS1 interfaces lt-0/1/0 unit 0 encapsulation ethernet user@host# set logical-systems LS1 interfaces lt-0/1/0 unit 0 peer-unit 1 user@host# set logical-systems LS1 interfaces lt-0/1/0 unit 0 family inet address 10.0.8.13/30 user@host# set logical-systems LS1 interfaces lt-0/1/0 unit 0 family iso

  3. Configure the logical tunnel interface on Logical System LS2.

    [edit]user@host# set logical-systems LS2 interfaces lt-0/1/0 unit 1 description LS2->LS1 user@host# set logical-systems LS2 interfaces lt-0/1/0 unit 1 encapsulation ethernet user@host# set logical-systems LS2 interfaces lt-0/1/0 unit 1 peer-unit 0 user@host# set logical-systems LS2 interfaces lt-0/1/0 unit 1 family inet address 10.0.8.14/30 user@host# set logical-systems LS2 interfaces lt-0/1/0 unit 1 family iso

  4. If you are done configuring the device, commit the configuration.

    [edit]user@host# commit

Verification

Confirm that the configuration is working properly.

Verifying That the Logical Systems Are Up

Purpose

Make sure that the interfaces are properly configured.

Action

user@host> show interfaces terse
Interface               Admin Link Proto    Local                 Remote
so-0/0/0                up    down
so-0/0/1                up    down
so-0/0/2                up    down
so-0/0/3                up    down
gr-0/1/0                up    up  
ip-0/1/0                up    up  
lt-0/1/0                up    up  
lt-0/1/0.0              up    up   inet     10.0.8.13/30    
                                   iso     
lt-0/1/0.1              up    up   inet     10.0.8.14/30    
                                   iso  
...

Verifying Connectivity Between the Logical Systems

Purpose

Make sure that the network address appears as directly connected.

Action

user@host> show route logical-system all
logical-system: LS1

inet.0: 2 destinations, 2 routes (2 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

10.0.8.12/30       *[Direct/0] 00:00:34
                    > via lt-0/1/0.0
10.0.8.13/32       *[Local/0] 00:00:34
                      Local via lt-0/1/0.0
-----
 
logical-system: LS2

inet.0: 2 destinations, 2 routes (2 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

10.0.8.12/30       *[Direct/0] 00:00:34
                    > via lt-0/1/0.1
10.0.8.14/32       *[Local/0] 00:00:34
                      Local via lt-0/1/0.1
...

Example: Connecting Logical Systems Within the Same Router Using Logical Tunnel Interfaces on MX Series Routers

This example shows how to configure logical tunnel interfaces to connect two logical systems that are configured in a single MX Series 3D Universal Edge Router.

Requirements

The MX Series router chassis must have a DPC, MPC, or MIC installed and in the online state.

Overview

To connect two logical systems, you configure a logical tunnel interface on both logical systems. Then you configure a peer relationship between the logical tunnel interfaces, thus creating a point-to-point connection. Logical tunnel interfaces behave like regular interfaces. You can configure them with Ethernet, Frame Relay, or another encapsulation type. You can also configure routing protocols across them. In effect, the logical tunnel (lt) interfaces connect two logical systems within the same router. The two logical systems do not share routing tables. This means that you can run dynamic routing protocols between different logical systems within the same router.

You must treat each interface like a point-to-point connection because you can only connect one logical tunnel interface to another at any given time. Also, you must select an interface encapsulation type, configure a corresponding protocol family, and set the logical interface unit number of the peering lt interface.

In this example, the logical tunnel interfaces are configured to behave as Ethernet interfaces with the encapsulation ethernet statement. The IS-IS Protocol is enabled on the logical tunnel interfaces with the family iso statement.

When configuring logical tunnel interfaces, note the following:

  • The peering logical interfaces must have the same lt interface name. For example, a logical unit on lt-0/1/0 cannot peer with a logical unit on lt-0/0/10. The FPC (DPC, MPC, or MIC), PIC, and port numbers must match.
  • The peering logical interfaces must be derived from the same module.
  • You can configure only one peer unit for each logical interface. For example, unit 0 cannot peer with both unit 1 and unit 2.

Figure 3 shows the topology used in this example.

Figure 3: Connecting Two Logical Systems

Connecting Two Logical Systems

Configuration

CLI Quick Configuration

To quickly configure this example, copy the following commands, paste them into a text file, remove any line breaks, change any details necessary to match your network configuration, and then copy and paste the commands into the CLI at the [edit] hierarchy level.

set chassis fpc 0 pic 1 tunnel-services bandwidth 1gset logical-systems LS1 interfaces lt-0/1/0 unit 0 description LS1->LS2 set logical-systems LS1 interfaces lt-0/1/0 unit 0 encapsulation ethernet set logical-systems LS1 interfaces lt-0/1/0 unit 0 peer-unit 1 set logical-systems LS1 interfaces lt-0/1/0 unit 0 family inet address 10.0.8.13/30 set logical-systems LS1 interfaces lt-0/1/0 unit 0 family iso set logical-systems LS2 interfaces lt-0/1/0 unit 1 description LS2->LS1 set logical-systems LS2 interfaces lt-0/1/0 unit 1 encapsulation ethernet set logical-systems LS2 interfaces lt-0/1/0 unit 1 peer-unit 0 set logical-systems LS2 interfaces lt-0/1/0 unit 1 family inet address 10.0.8.14/30 set logical-systems LS2 interfaces lt-0/1/0 unit 1 family iso

Step-by-Step Procedure

The following example requires you to navigate various levels in the configuration hierarchy. For information about navigating the CLI, see Using the CLI Editor in Configuration Mode in the CLI User Guide.

To connect logical system interfaces:

  1. Run the show chassis fpc command to verify that the router has a DPC, MPC, or MIC installed and is in the online state.
    user@host> show chassis fpc
                         Temp  CPU Utilization (%)   Memory    Utilization (%)
Slot State            (C)  Total  Interrupt      DRAM (MB) Heap     Buffer
  0  Online            31      4          0       1024       14         21
  1  Empty           
  2  Empty

    This output shows that slot 1 and slot 2 are empty. Slot 0 is online.

  2. Configure FPC slot 0 to support logical tunnel (lt) interfaces.

    [edit]user@host# set chassis fpc 0 pic 1 tunnel-services bandwidth 1g
    This command creates several tunnel interface types, including gr, ip, and lt. For this example, the important one is the logical tunnel (lt) interface.

  3. Commit the configuration.

    [edit]user@host# commit
  4. Run the show interfaces terse command to verify that the router has a logical tunnel (lt) interface.
    user@host> show interfaces terse
    Interface               Admin Link Proto    Local                 Remote
...
gr-0/1/0                up    up  
ip-0/1/0                up    up  
lt-0/1/0                up    up  
...

  5. Configure the logical tunnel interface on Logical System LS1.

    [edit]user@host# set logical-systems LS1 interfaces lt-0/1/0 unit 0 description LS1->LS2 user@host# set logical-systems LS1 interfaces lt-0/1/0 unit 0 encapsulation ethernet user@host# set logical-systems LS1 interfaces lt-0/1/0 unit 0 peer-unit 1 user@host# set logical-systems LS1 interfaces lt-0/1/0 unit 0 family inet address 10.0.8.13/30 user@host# set logical-systems LS1 interfaces lt-0/1/0 unit 0 family iso

  6. Configure the logical tunnel interface on Logical System LS2.

    [edit]user@host# set logical-systems LS2 interfaces lt-0/1/0 unit 1 description LS2->LS1 user@host# set logical-systems LS2 interfaces lt-0/1/0 unit 1 encapsulation ethernet user@host# set logical-systems LS2 interfaces lt-0/1/0 unit 1 peer-unit 0 user@host# set logical-systems LS2 interfaces lt-0/1/0 unit 1 family inet address 10.0.8.14/30 user@host# set logical-systems LS2 interfaces lt-0/1/0 unit 1 family iso

  7. If you are done configuring the device, commit the configuration.

    [edit]user@host# commit

Verification

Confirm that the configuration is working properly.

Verifying That the Logical Systems Are Up

Purpose

Make sure that the interfaces are properly configured.

Action

user@host> show interfaces terse
Interface               Admin Link Proto    Local                 Remote
so-0/0/0                up    down
so-0/0/1                up    down
so-0/0/2                up    down
so-0/0/3                up    down
gr-0/1/0                up    up  
ip-0/1/0                up    up  
lt-0/1/0                up    up  
lt-0/1/0.0              up    up   inet     10.0.8.13/30    
                                   iso     
lt-0/1/0.1              up    up   inet     10.0.8.14/30    
                                   iso  
...

Verifying Connectivity Between the Logical Systems

Purpose

Make sure that the network address appears as directly connected.

Action

user@host> show route logical-system all
logical-system: LS1

inet.0: 2 destinations, 2 routes (2 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

10.0.8.12/30       *[Direct/0] 00:00:34
                    > via lt-0/1/0.0
10.0.8.13/32       *[Local/0] 00:00:34
                      Local via lt-0/1/0.0
-----
 
logical-system: LS2

inet.0: 2 destinations, 2 routes (2 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

10.0.8.12/30       *[Direct/0] 00:00:34
                    > via lt-0/1/0.1
10.0.8.14/32       *[Local/0] 00:00:34
                      Local via lt-0/1/0.1
...
 

Related Documentation

 

Published: 2013-08-28

Supported Platforms

 

Related Documentation

 

Published: 2013-08-28

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