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Initial Configuration of Ethernet Interfaces

 

Ethernet Interfaces are networking Interfaces that provide traffic connectivity. You can configure physical Interfaces as well as the logical Interfaces on your device. This topic discusses how to configure the physical properties of an Interface specific to Fast-Ethernet Interfaces, Gigabit-Ethernet Interfaces, and aggregated Ethernet Interfaces. You can also use this topic for information on how to configure the speed of the Interface, limit the rate at which ingress traffic arrives on Fast-Ethernet ports, configure the Interface to operate in full-duplex or half-duplex mode, configure MAC address validation on static Ethernet Interfaces, and other basic configurations.

Configuring Ethernet Physical Interface Properties

To configure physical interface properties, for Fast Ethernet and Gigabit-Ethernet, DWDM interfaces, and other interfaces, complete the following steps:

  1. To configure Fast Ethernet-specific physical interface properties, include the fastether-options statement at the [edit interfaces fe-fpc/pic/port] hierarchy level:
    Note

    The speed statement applies to the management Ethernet interface (fxp0 or em0), the Fast Ethernet 12-port and 48-port Physical Interface Card (PIC) interfaces and the MX Series Tri-Rate Ethernet copper interfaces. The Fast Ethernet, fxp0, and em0 interfaces can be configured for 10 Mbps or 100 Mbps (10m | 100m). The MX Series Tri-Rate Ethernet copper interfaces can be configured for 10 Mbps, 100 Mbps, or 1 Gbps (10m | 100m | 1g). The 4-port and 8-port Fast Ethernet PICs support a speed of 100 Mbps only.

    MX Series routers support Gigabit Ethernet automatic line sensing of MDI (Media Dependent Interface) and MDIX (Media Dependent Interface with Crossover) port connections. MDI is the Ethernet port connection typically used on network interface cards (NIC). MDIX is the standard Ethernet port wiring for hubs and switches. This feature allows MX Series routers to automatically detect MDI and MDIX connections and configure the router port accordingly. You can disable this feature by using the no-auto-mdix statement at the [edit interfaces ge-fpc/pic/port] hierarchy level.

    Note

    Junos OS supports Ethernet host addresses with no subnets. This enables you to configure an Ethernet interface as a host address (that is, with a network mask of /32), without requiring a subnet. Such interfaces can serve as OSPF point-to-point interfaces, and MPLS is also supported.

  2. To configure physical interface properties specific to Gigabit Ethernet and 10-Gigabit Ethernet, include the gigether-options statement at the [edit interfaces ge-fpc/pic/port] or [edit interfaces xe-fpc/pic/port] hierarchy level:
  3. For 10-Gigabit Ethernet DWDM-specific physical interface properties, include the optics-options statement at the [edit interfaces ge-fpc/pic/port] hierarchy level:

    To configure Gigabit Ethernet IQ-specific physical interface properties, include the gigether-options statement at the [edit interfaces ge-fpc/pic/port] hierarchy level. These statements are supported on 10-Gigabit Ethernet IQ2 and IQ2-E PIC. Some of these statements are also supported on Gigabit Ethernet PICs with small form-factor pluggable transceivers (SFPs) (except the 10-port Gigabit Ethernet PIC and the built-in Gigabit Ethernet port on the M7i router).

  4. To configure 10-Gigabit Ethernet physical interface properties, include the lan-phy or wan-phy statement at the [edit interfaces xe-fpc/pic/port framing] hierarchy level.
  5. To configure OAM 802.3ah support for Ethernet interfaces, include the oam statement at the [edit protocols] hierarchy level.
  6. To configure Gigabit Ethernet IQ-specific logical interface properties, include the input-vlan-map, output-vlan-map, layer2-policer, and vlan-tags statements at the [edit interfaces interface-name unit logical-unit-number] hierarchy level or [edit logical-systems logical-system-name interfaces interface-name unit logical-unit-number].
  7. To configure aggregated Ethernet-specific physical interface properties, include the aggregated-ether-options statement at the [edit interfaces aex] hierarchy level:

Configuring the Interface Speed on Ethernet Interfaces

For M Series and T Series Fast Ethernet 12-port and 48-port PIC interfaces, the management Ethernet interface (fxp0 or em0), and the MX Series Tri-Rate Ethernet copper interfaces, you can explicitly set the interface speed. The Fast Ethernet, fxp0, and em0 interfaces can be configured for 10 Mbps or 100 Mbps (10m | 100m). The MX Series Tri-Rate Ethernet copper interfaces can be configured for 10 Mbps, 100 Mbps, or 1 Gbps (10m | 100m | 1g). For information about management Ethernet interfaces and to determine the management Ethernet interface type for your router, see Understanding Management Ethernet Interfaces and Supported Routing Engines by RouterMX Series routers, with MX-DPC and Tri-Rate Copper SFPs, support 20x1 Copper to provide backwards compatibility with 100/10BASE-T and 1000BASE-T operation through an Serial Gigabit Media Independent Interface (SGMII) interface.

  1. In configuration mode, go to the [edit interfaces interface-name] hierarchy level.
  2. To configure the speed, include the speed statement at the [edit interfaces interface-name] hierarchy level.
Note
  • By default, the M Series and T Series routers management Ethernet interface autonegotiates whether to operate at 10 megabits per second (Mbps) or 100 Mbps. All other interfaces automatically choose the correct speed based on the PIC type and whether the PIC is configured to operate in multiplexed mode (using the no-concatenate statement in the [edit chassis] configuration hierarchy.

  • Starting with Junos OS Release 14.2 the auto-10m-100m option allows the fixed tri-speed port to auto negotiate with ports limited by 100m or 10mmaximum speed. This option must be enabled only for Tri-rate MPC port, that is, 3D 40x 1GE (LAN) RJ45 MIC on MX platform. This option does not support other MICs on MX platform.,

  • When you manually configure Fast Ethernet interfaces on the M Series and T Series routers, link mode and speed must both be configured. If both these values are not configured, the router uses autonegotiation for the link and ignores the user-configured settings.

  • If the link partner does not support autonegotiation, configure either Fast Ethernet port manually to match its link partner's speed and link mode. When the link mode is configured, autonegotiation is disabled.

  • On MX Series routers with tri-rate copper SFP interfaces, if the port speed is negotiated to the configured value and the negotiated speed and interface speed do not match, the link will not be brought up.

  • When you configure the Tri-Rate Ethernet copper interface to operate at 1 Gbps, autonegotiation must be enabled.

  • Starting with Junos OS Release 11.4, half-duplex mode is not supported on Tri-Rate Ethernet copper interfaces. When you include the speed statement, you must include the link-mode full-duplex statement at the same hierarchy level.

See also

Configuring the Ingress Rate Limit

On Fast Ethernet 8-port, 12-port, and 48-port PIC interfaces only, you can apply port-based rate limiting to the ingress traffic that arrives at the PIC.

To configure an ingress rate limit on a Fast Ethernet 8-port, 12-port, or 48-port PIC interface, include the ingress-rate-limit statement at the [edit interfaces interface-name fastether-options] hierarchy level:

rate can range in value from 1 through 100 Mbps.

Full-duplex communication means that both ends of the communication can send and receive signals at the same time. Half-duplex is also bidirectional communication, but signals can flow in only one direction at a time.

By default, the router’s management Ethernet interface, fxp0 or em0, autonegotiates whether to operate in full-duplex or half-duplex mode. Fast Ethernet interfaces, can operate in either full-duplex or half-duplex mode, and all other interfaces can operate only in full-duplex mode. For Gigabit Ethernet and 10-Gigabit Ethernet, the link partner must also be set to full duplex.

Note

For M Series, MX Series, and most T Series routers, the management Ethernet interface is fxp0. For T1600 and T4000 routers configured in a routing matrix, and TX Matrix Plus routers, the management Ethernet interface is em0.

Note

Automated scripts that you have developed for standalone T1600 routers (T1600 routers that are not in a routing matrix) might contain references to the fxp0 management Ethernet interface. Before reusing the scripts on T1600 routers in a routing matrix, edit the command lines that reference the fxp0 management Ethernet interface so that the commands reference the em0 management Ethernet interface instead.

Note

When you configure the Tri-Rate Ethernet copper interface to operate at 1 Gbps, autonegotiation must be enabled.

Note

When you manually configure Fast Ethernet interfaces on the M Series and T Series routers, link mode and speed must both be configured. If both these values are not configured, the router uses autonegotiation for the link and ignores the user-configured settings.

Note

Member links of an aggregated Ethernet bundle must not be explicitly configured with a link mode. You must remove any such link-mode configuration before committing the aggregated Ethernet configuration.

To explicitly configure an Ethernet interface to operate in either full-duplex or half-duplex mode, include the link-mode statement at the [edit interfaces interface-name] hierarchy level:

Note

Starting with Junos OS release 17.4R1 and later, the link-mode configuration is not supported for 10-Gigabit Ethernet interfaces.

See also

Configuring Multicast Statistics Collection on Ethernet Interfaces

T Series and TX Matrix routers support multicast statistics collection on Ethernet interfaces in both ingress and egress directions. The multicast statistics functionality can be configured on a physical interface thus enabling multicast accounting for all the logical interfaces below the physical interface.

The multicast statistics information is displayed only when the interface is configured with the multicast-statistics statement, which is not enabled by default.

Multicast statistics collection requires at least one logical interface is configured with family inet and/or inet6; otherwise, the commit for multicast-statistics will fail.

The multicast in/out statistics can be obtained via interfaces statistics query through CLI and via MIB objects through SNMP query.

To configure multicast statistics:

  1. Include the multicast-statistics statement at the [edit interfaces interface-name] hierarchy level.

An example of a multicast statistics configuration for a Ethernet interface follows:

To display multicast statistics, use the show interfaces interface-name statistics detail command.

MAC Address Validation on Static Ethernet Interfaces Overview

MAC address validation enables the router to validate that received packets contain a trusted IP source and an Ethernet MAC source address.

MAC address validation is supported on AE, Fast Ethernet, Gigabit Ethernet, and 10–Gigabit Ethernet interfaces (with or without VLAN tagging) on MX Series routers only.

There are two types of MAC address validation that you can configure:

  • Loose—Forwards packets when both the IP source address and the MAC source address match one of the trusted address tuples.

    Drops packets when the IP source address matches one of the trusted tuples, but the MAC address does not support the MAC address of the tuple

    Continues to forward packets when the source address of the incoming packet does not match any of the trusted IP addresses.

  • Strict—Forwards packets when both the IP source address and the MAC source address match one of the trusted address tuples.

    Drops packets when the MAC address does not match the tuple's MAC source address, or when IP source address of the incoming packet does not match any of the trusted IP addresses.

Configuring MAC Address Validation on Static Ethernet Interfaces

MAC address validation enables the router to validate that received packets contain a trusted IP source and an Ethernet MAC source address. MAC address validation is supported on AE, Fast Ethernet, Gigabit Ethernet, and 10–Gigabit Ethernet interfaces (with or without VLAN tagging) on MX Series routers only.

To configure MAC address validation on static Ethernet Interfaces:

  1. In the configuration mode, at the [edit] hierarchy level, configure the static Ethernet interface.
  2. Configure the protocol family and the logical unit of the interface at the [edit interfaces interface-name] hierarchy level. While configuring the protocol family, specify inet as the protocol family.
  3. Configure MAC address validation on the static Ethernet Interface. You can specify the type of MAC address validation you require. Possible values are: Strict and Loose. You can also specify the interface address.
  4. Configure the static ARP entry by specifying the IP address and the MAC address that are to be mapped. The IP address specified must be part of the subnet defined in the enclosing address statement. The MAC address must be specified as hexadecimal bytes in the following formats: nnnn.nnnn.nnnn or nn:nn:nn:nn:nn:nnformat. For instance, you can use either 0011.2233.4455 or 00:11:22:33:44:55.

Displaying Internal Ethernet Interfaces for a Routing Matrix with a TX Matrix Plus Router

The router internal Ethernet interface connects the Routing Engine with the router’s packet forwarding components. The Junos OS automatically configures internal Ethernet interfaces. For TX Matrix Plus routers, the internal Ethernet interfaces are ixgbe0 and ixgbe1. For T1600 routers configured in a routing matrix, the internal Ethernet interfaces are bcm0 and em1. For more information about internal Ethernet interfaces, see Understanding Internal Ethernet Interfaces.

Note

Do not modify or remove the configuration for the internal Ethernet interface that the Junos OS automatically configures. If you do, the router will stop functioning.

The following example is a sequence of show interfaces commands issued in a Junos OS command-line interface (CLI) session with a TX Matrix Plus router in a routing matrix. In the example, the TX Matrix Plus router, which is also called the switch-fabric chassis (SFC), is known by the IP host name host-sfc-0 and contains redundant Routing Engines. The commands display information about the management Ethernet interface and both internal Ethernet interfaces configured on the Routing Engine to which you are currently logged in:

user@host-sfc-0> show interfaces em0 terse
user@host-sfc-0> show interfaces ixgbe0 terse
user@host-sfc-0> show interfaces ixgbe1 terse

The following example is a sequence of show interfaces commands issued in a CLI session with a T1600 router in a routing matrix. In the example, the T1600 router, which is also called the line-card chassis (LCC), is known by the IP host name host-sfc-0-lcc-2 and contains redundant Routing Engines.

This T1600 router is connected to the routing matrix through a connection in the TXP-SIB-F13 in slot 2 of the SCC. The commands display information about the management Ethernet interface and both internal Ethernet interfaces configured on the Routing Engine to which you are currently logged in:

Note

In a routing matrix, the show interfaces command displays information about the current router only. If you are logged in to the TX Matrix Plus router, the show interfaces command output does not include information about any of the attached T1600 routers. To display interface information about a specific T1600 router in the routing matrix, you must first log in to that router.

The previous example shows a CLI session with the TX Matrix Plus router. To display interface information about the T1600 router known as host-sfc-0-lcc-2, first use the request routing-engine login command to log in to that LCC.

user@host-sfc-0> request routing-engine login lcc 2
user@host-sfc-0-lcc-2> show interfaces em0 terse
user@host-sfc-0-lcc-2> show interfaces bcm0 terse
user@host-sfc-0-lcc-2> show interfaces em1 terse

Example: Configuring Fast Ethernet Interfaces

The following configuration is sufficient to get a Fast Ethernet interface up and running. By default, IPv4 Fast Ethernet interfaces use Ethernet version 2 encapsulation.

Example: Configuring Gigabit Ethernet Interfaces

The following configuration is sufficient to get a Gigabit Ethernet, Tri-Rate Ethernet copper, or 10-Gigabit Ethernet interface up and running. By default, IPv4 Gigabit Ethernet interfaces on MX Series, M Series, and T Series routers use 802.3 encapsulation.

The M160, M320, M120, T320, and T640 2-port Gigabit Ethernet PIC supports two independent Gigabit Ethernet links.

Each of the two interfaces on the PIC is named:

Each of these interfaces has functionality identical to the Gigabit Ethernet interface supported on the single-port PIC.

Release History Table
Release
Description
Starting with Junos OS Release 14.2 the auto-10m-100m option allows the fixed tri-speed port to auto negotiate with ports limited by 100m or 10mmaximum speed. This option must be enabled only for Tri-rate MPC port, that is, 3D 40x 1GE (LAN) RJ45 MIC on MX platform. This option does not support other MICs on MX platform.
Starting with Junos OS Release 11.4, half-duplex mode is not supported on Tri-Rate Ethernet copper interfaces. When you include the speed statement, you must include the link-mode full-duplex statement at the same hierarchy level.