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Gigabit Ethernet Interface

SUMMARY You can configure Gigabit Ethernet Interface with various modes like speed options, autonegotiation options, VLAN options, IP options, interface modes, link settings on the switches. The configuration uses Junos OS for EX Series switches with support for the Enhanced Layer 2 Software (ELS) configuration style.

Speed and Autonegotiation

Configure Interface Speed on Switches

On 1/10G capable Gigabit Ethernet SFP interfaces, the duplex is always full and the speed matches that of the inserted optic. These interfaces support either 1G or 10G SFP optics.

  • For EX and QFX products, the CLI configuration needs to match the optic speed. For 1G based optics, the configuration needs to start with ge-. For 10G inserted optics, the configuration needs to start with xe-. By default, both ge and xe choices are in the default configuration. User must match the CLI syntax to the optic speed.

Note:

Only 10 Gbps and 40 Gbps interfaces are supported on OCX Series switches.

Following are the steps to configure the speeds on EX and QFX platforms:

  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.

Configure Speed on EX2300-48MP and EX2300-24MP Switches

Follow these guidelines when you configure the speed on EX4300-48MP switches:

  • The mge interface is a rate-selectable (multirate) Gigabit Ethernet interface that support speeds of 10-Gbps, 5-Gbps, and 2.5-Gbps over CAT5e/CAT6/CAT6a cables. In the EX2300, the mge interface supports 100-Mbps, 1-Gbps, and 2.5-Gbps speeds. Note that 10 Mbps speed is supported only on ge interfaces of EX2300 switch.

  • You can configure both multi-rate gigabit ethernet interface (mge) and gigabit ethernet (ge) interface using the speed configuration statement.

  • The Multi-rate gigabit ethernet interface (MGE) on EX2300-24MP and EX2300-48MP switches flaps (becomes unavailable, and then available again) while performing timeout detection and recovery (TDR) test.

  • If both Energy Efficient Ethernet (EEE) and 100-Mbps speed are configured on a rate-selectable (or multirate) Gigabit Ethernet (mge) port, the port operates only at 100-Mbps speed but EEE is not enabled on that port. EEE is supported only on mge interfaces that operate at 1-Gbps and 2.5-Gbps speeds.

Configure Speed and Autonegotiation on QFX5100-48T Switches

For information about speed support, see speed.

Table 1 provides QFX5100-48T details and description.

Table 1: QFX5100-48T details and description

Detail

Description

Duplex Mode

Full duplex

Autonegotiation

The autonegotiation option is to negotiate the speeds.

10 Gbps, 1 Gbps - By default, autonegotiation enabled

100 Mbps - Autonegotiation not supported

Following are guidelines for configuring speed and autonegotiation on QFX5100-48T switch:

  • If the speed on the switch is set to 10-Gbps or auto, the switch advertises all the speeds.

  • If the speed on the switch is set to 1-Gbps or 100-Gbps, the switch advertises only the respective speeds (1-Gbps or 100-Gbps).

  • Whenever you connect a new device to a previously used interface, the switch operates in auto-negotiate mode, unless already set to a fixed speed.

  • The no-auto-negotiation statement does no action. Hence, it is recommended not to use the no-auto-negotiation statement.

Table 2 provides the configuration steps to configure speed and autonegotiation.

Table 2: Configure Speed and Autonegotiation

Configure Speed/Autonegotiation

Use Configuration

To configure a particular speed, mention the speed.

For a port to only advertise a specific speed, start with a specific speed, it is mandatory that both the auto-negotiation option must be set (enabled) and the interface must also be configured with a specific supported speed. 

set interfaces xe-0/0/0 ether-options auto-negotiation 
set interfaces xe-0/0/0 speed speed

For example to configure 1-Gbps speed, execute the following command:

set interfaces xe-0/0/0 ether-options auto-negotiation 
set interfaces xe-0/0/0 speed 1g

To enable auto-negotiation and advertise all speeds.

With or without below, QFX5100-48T interface support auto-negotiation to one of either 10G and 1G.

set interfaces xe-0/0/0 ether-options auto-negotiation
set interfaces xe-0/0/0 speed auto

This configuration does not change any functionality. If the speed is set to fixed at 10G, the interface still operates as auto, and advertises 10G/1G/100M.

When you configure a port using the speed auto option, the port deletes the last configured speed, comes up again and advertises all the possible speeds.

Autonegotiation Support for EX4300-48MP Switches

The 4-port 1-Gigabit Ethernet/10-Gigabit Ethernet uplink module (EX-UM-4SFPP-MR) on EX4300-48MP switches supports 1-Gbps speed. You do not need to explicitly configure 1-Gbps speed on the uplink module as it automatically identifies the installed 1-gigabit SFP transceivers and creates the interface accordingly.

If both Energy Efficient Ethernet (EEE) and 100-Mbps speed are configured on a rate-selectable (or multirate) Gigabit Ethernet (mge) port, the port operates only at 100-Mbps speed but EEE is not enabled on that port. Note that EEE is supported only on mge interfaces that operate at 1-Gbps, 2.5-Gbps, 5-Gbps, and 10-Gbps speeds.

For information about speed support, see Speed and Autonegotiation support on EX4300-48MP switches.

On EX4300-48MP, the status LED of 1-Gigabit Ethernet uplink module port is solid green (instead of blinking green) because of a device limitation. However, there is no impact on device functionality.

Table 3 summarizes the autonegotiation and half duplex support on EX4300-48MP switches.

Table 3: Autonegotiation and Half-Duplex Support for EX4300-48MP Switches

Port Numbers

Interface Name

Autonegotiation Supported (YES/NO) ?

Half Duplex Supported (YES/NO) ?

PIC 0 PORTS 24-47

mge

Yes. Speed supported (10G/5G/2.5G/1G/100m)

No

PIC 2 PORT 0 – 3 (Uplink ports)

xe

No

No

PIC 0 PORTS 0 – 23

ge

1G/100M/10M

Yes, but Half duplex cannot be configured on EX4300-48MP switches. If the link partner is half duplex and capable of autonegotiating half duplex, then these ports can work a half duplex.

PIC 2 PORT 0 - 3

Uplink 4x10G

No. Based on inserted transceiver port will be a GE for 1G SFP and XE for 10G SFP.

No

PIC 2 PORT 0, 1

Uplink 2x40G

No

No

Autonegotiation support for EX4600-40F, QFX5110-48S and QFX5100-48S with JNP-SFPP-10GE-T transceiver

The interfaces on which the JNP-SFPP-10GE-T transceivers are present come up based on the speed (100-Mbps, or 1Gbps, or 10-Gbps) configured using the set interfaces interface-name speed speed command at the remote end.

For information about platforms support, see Hardware Compatibility Tool.

Table 4 discusses EX4600-40F, QFX5110-48S and QFX5100-48S switches with JNP-SFPP-10GE-T transceiver details.

Table 4: QFX5110-48S and QFX5100-48S switches with JNP-SFPP-10GE-T transceiver details and description

Details

Description

EX4600-40F, QFX5110-48S and QFX5100-48S switches with JNP-SFPP-10GE-T transceiver

Interface created - Multirate gigabit Ethernet (mge) interface.

The mge interface is a rate-selectable (multirate) Gigabit Ethernet interface that can support 10-Gbps speed over CAT5e/CAT6/CAT6a cables. On EX4600-40F, QFX5110-48S and QFX5100-48S, the mge interface supports 10-Gbps, 1-Gbps, and 100-Mbps speeds, which can be configured using the speed configuration statement.

Use the set interfaces mge-0/0/0 speed (100M|1G|10G) command to configure the speed and autonegotiation.

EX4600-40F, QFX5110-48S and QFX5100-48S switches with other transceivers

Interface created - ge or the xe interface.

Duplex Mode

Full duplex

Viewing Media Specific Information

You can execute the show interfaces media command to view the media-specific information. In the output of show interfaces name media, the output field speed displays the speed configured for the mge interface (with a default of 10G). The configured speed signifies the highest speed that the JNP-SFPP-10GE-T is capable of working at. You should enable auto-negotiation for the JNP-SFPP-10GE-T, unless it works in 100-Mbps speed where it can use the parallel detect capability using which it can detect when the link partner is in forced 100BASE-TX mode and bring the link up. The speed displayed under the Link partner denotes the actual speed at which the link is working. The Link partner speed is dynamic and displays the highest speed that both ends have negotiated and can work at.

When the interface is configured with a particular speed, it means that the transceiver can support connection to a peer at rates lesser than or equal to the configured speed, as shown in Table 5:

Table 5: Interface speed based on configured speed and remote end speed

Configured Speed

The interface will be up with remote end speed of

10G

10G, 1G, and 100M

1G

1G and 100M

100M

100M

Autonegotiation support for QFX5120-48Y with JNP-SFPP-10GE-T transceiver

For information about platforms support, see Hardware Compatibility Tool.

Table 6 discusses QFX5120-48Y with JNP-SFPP-10GE-T transceiver details.

Table 6: QFX5120-48Y with JNP-SFPP-10GE-T transceiver details and description

Details

Description

Supported speeds

10 Gbps and 1 Gbps

Default speed: 10 Gbps (with or without JNP-SFPP-10GE-T transceiver connected)

If the peer does not support 10-Gbps speed, then the link will be down.

Duplex Mode

Full duplex

Table 7 configure 1-Gbps and 10-Gbps speeds on QFX5120-48Y with JNP-SFPP-10GE-T transceiver.

Table 7: Configure and delete 1-Gbps speed

Configure Speed

Description

1 Gbps

Use the set chassis fpc 0 pic 0 port port-number speed 1G command. Due to hardware limitations, you can configure the port-number value only in multiples of four, starting from port 0. You must also configure sets of four consecutive ports (for example, 0-3, 4-7, and so on) to operate at the common speed.

On QFX5120 switch, multirate gigabit Ethernet (mge) interfaces are not supported due to hardware limitations.

To revert to 10-Gbps speed (after setting 1-Gbps speed

Delete the 1G speed configuration

See Also

Configuring Gigabit and 10-Gigabit Ethernet Interfaces for EX4600 and QFX Series Switches

Devices include a factory default configuration that:

  • Enables all 10-Gigabit Ethernet network interfaces on the switch

  • Sets a default port mode (access)

  • Sets default link settings

  • Specifies a logical unit (unit 0) and assigns it to family ethernet-switching

  • Configures Storm Control on all 10-Gigabit Ethernet network interfaces

  • Provides basic Rapid Spanning Tree Protocol (RSTP) and Link Layer Discovery Protocol (LLDP) configuration

The ether-options statement enables you to modify the following options:

  • 802.3ad—Specify an aggregated Ethernet bundle for both Gigabit Ethernet and 10-Gigabit Ethernet interfaces.

  • autonegotiation—Enable or disable autonegotation of flow control, link mode, and speed for interfaces.

  • link-mode—Specify full-duplex, half-duplex, or automatic for Gigabit Ethernet interfaces.

  • loopback—Enable or disable a loopback interface for both Gigabit Ethernet and 10-Gigabit Ethernet interfaces.

To set ether-options for both Gigabit Ethernet and 10-Gigabit Ethernet interfaces:

This topic describes:

Configuring Port Mode on QFX5100-48S, QFX5100-48T, QFX5100-24Q, and EX4600 Switches

If you are connecting a switch to other switches and to routers on the LAN, you need to assign the interface to a logical port and you need to configure the logical port as a trunk port.

To configure a Gigabit Ethernet or 10-Gigabit interface for trunk port mode on the Enhanced Layer 2 software (ELS):

See Also

Configuring the Link Settings for Gigabit Ethernet Interfaces on QFX5100-48S, QFX5100-96S, and EX4600 Switches

Devices include a factory default configuration that enables Gigabit Ethernet interfaces with applicable link settings.

The following default configurations are available on Gigabit Ethernet interfaces:

  • You cannot set the speed on these interfaces.

    On QFX5100-48S and QFX5100-96S devices using 1-Gigabit Ethernet SFP interfaces, the speed is set to 1 Gbps by default and cannot be configured to operate in a different speed.

  • On QFX5100 devices, the interface naming for Gigabit Ethernet interfaces changes automatically to xe-0/0/0, ge-0/0/0, or et-0/0/0 when the appropriate SFP is inserted.

  • Gigabit Ethernet interfaces operate in full-duplex mode.

  • Autonegotiation is supported by default. Autonegotiation is enabled by default, and will autonegotiate the speed with the link partner. We recommend that you keep autonegotiation enabled for interfaces operating at 100M and 1G. By default, autonegotiation is disabled on 10-Gigabit fiber ports.

    If for some reason you have disabled autonegotiation, you can enable it by issuing the set interfaces name ether-options auto-negotiate command.

    To disable autonegotiation, issue the delete interfaces name ether-options auto-negotiate command.

    Note:

    Do not use the set interfaces name ether-options no-auto-negoatiate command to remove the autonegotiation configuration.

    Issue the show interfaces name extensive command to see if autonegotiation is enabled or disabled and the negotiated speed of the interface.

Configuring Gigabit Ethernet Interfaces on QFX5100-48T Switches

Devices include a factory default configuration that enables Gigabit Ethernet interfaces with applicable link settings.

The following default configurations are available on Gigabit Ethernet interfaces:

  • Gigabit Ethernet interfaces operate in full-duplex mode.

  • Gigabit Ethernet interfaces must be configured as xe-fpc/pic/port, and not ge-fpc/pic/port.

  • Autonegotiation is enabled by default, and will autonegotiate the speed with the link partner. We recommend that you keep autonegotiation enabled for interfaces operating at 1G and 10G. By default, autonegotiation is enabled on 10-Gigabit Ethernet Copper interfaces.

    To disable autonegotiation, issue the delete interfaces name ether-options auto-negotiate command. Note that you can not disable auto-negotiation on 1-Gigabit Ethernet ports. It is mandatory to enable autonegotiation when 1-Gbps speed is configured on a particular interface.

    Note:

    Do not use the set interfaces name ether-options no-auto-negotiate command to remove the autonegotiation configuration.

    You can reenable autonegotation it by issuing the set interfaces name ether-options auto-negotiate command.

    Issue the show interfaces name extensive command to see if autonegotiation is enabled or disabled and the negotiated speed of the interface.

  • For a port to start with a specific speed, it is mandatory that both the auto-negotiation must be enabled and interface must be configured with a particular speed. Otherwise, the switch will remain with the last negotiated speed.

Configuring the Link Settings for 10-Gigabit Ethernet Interfaces on QFX5100-48S, QFX5100-24Q, QFX5100-96S, and EX4600 Switches

The following default configurations are available on 10-Gigabit Ethernet interfaces:

  • All the 10-Gigabit Ethernet interfaces are set to auto-negotiation.

  • Flow control for 10-Gigabit Ethernet interfaces is set to enabled by default. You can disable flow control by specifying the no-flow-control option.

  • The speed cannot be configured.

    On QFX5100-48S, QFX5100-96S, and QFX5100-24Q devices using 10-Gigabit Ethernet SFP interfaces, the speed is set to 10 Gbps by default and cannot be configured to operate in a different speed.

  • On QFX5100 devices, the interface naming for Gigabit Ethernet interfaces changes automatically to xe-0/0/0, ge-0/0/0, or et-0/0/0 when the appropriate SFP is inserted.

  • 10-Gigabit Ethernet interfaces operate in full-duplex mode by default.

  • Autonegotiation is enabled by default, and will autonegotiate the speed with the link partner. We recommend that you keep autonegotiation enabled for interfaces operating at 100M and 1G. By default, autonegotiation is disabled on 10-Gigabit fiber ports.

    If for some reason you have disabled autonegotiation, you can enable it by issuing the set interfaces name ether-options auto-negotiate command.

    To disable autonegotiation, issue the delete interfaces name ether-options auto-negotiate command.

    Note:

    Do not use the set interfaces name ether-options no-auto-negoatiate command to remove the autonegotiation configuration.

    Issue the show interfaces name extensive command to see if autonegotiation is enabled or disabled and the negotiated speed of the interface.

Configuring the Link Settings for 10-Gigabit Ethernet Interfaces on QFX5100-48T Switches

The following default configurations are available on 10-Gigabit Ethernet interfaces:

  • All the 10-Gigabit Ethernet interfaces are set to auto-negotiation.

  • Flow control for 10-Gigabit Ethernet interfaces is set to enabled by default. You can disable flow control by specifying the no-flow-control option.

  • 10-Gigabit Ethernet interfaces operate in full-duplex mode by default.

  • Autonegotiation is enabled by default, and will autonegotiate the speed with the link partner. We recommend that you keep autonegotiation enabled for interfaces operating at 1G and 10G.

    Note:

    On QFX5100-48T-6Q switches, autonegotiation is not supported for 100-Mbps speed.

    If for some reason you have disabled autonegotiation, you can enable it by issuing the set interfaces name ether-options auto-negotiate command.

    Issue the show interfaces name extensive command to see if autonegotiation is enabled or disabled and the negotiated speed of the interface.

Configuring the IP Options on QFX5100-48S, QFX5100-48T, QFX5100-24Q, and EX4600 Switches

To specify an IP address for the logical unit:

See Also

Configuring Gigabit Ethernet Interfaces for EX Series Switches with ELS support

Note:

This task uses Junos OS for EX Series switches with support for the Enhanced Layer 2 Software (ELS) configuration style. If your switch runs software that does not support ELS, see Configuring Gigabit Ethernet Interfaces (CLI Procedure). For ELS details, see Using the Enhanced Layer 2 Software CLI.

An Ethernet interface must be configured for optimal performance in a high-traffic network. EX Series switches include a factory default configuration that:

  • Enables all the network interfaces on the switch

  • Sets a default interface mode (access)

  • Sets default link settings

  • Specifies a logical unit (unit 0) and assigns it to family ethernet-switching (except on EX8200 switches and Virtual Chassis)

  • Specifies Rapid Spanning Tree Protocol (RSTP) and Link Layer Discovery Protocol (LLDP)

This topic describes:

Configuring VLAN Options and Interface Mode

By default, when you boot a switch and use the factory default configuration, or when you boot the switch and do not explicitly configure a port mode, all interfaces on the switch are in access mode and accept only untagged packets from the VLAN named default. You can optionally configure another VLAN and use that instead of default. You can also configure a port to accept untagged packets from the user-configured VLAN. For details on this concept (native VLAN), see Understanding Bridging and VLANs on Switches.

If you are connecting either a desktop phone, wireless access point or a security camera to a Power over Ethernet (PoE) port, you can configure some parameters for the PoE interface. PoE interfaces are enabled by default. For detailed information about PoE settings, see Configuring PoE Interfaces on EX Series Switches.

If you are connecting a device to other switches and to routers on the LAN, you need to assign the interface to a logical port and configure the logical port as a trunk port. See Port Role Configuration with the J-Web Interface (with CLI References) for more information about port configuration.

If you are connecting to a server that contains virtual machines and a VEPA for packet aggregation from those virtual machines, configure the port as a tagged-access port. See Understanding Bridging and VLANs on Switches for more information about tagged access.

To configure a 1-Gigabit, 10-Gigabit, or 40-Gigabit Ethernet interface for trunk port mode:

See Also

Configuring the Link Settings

EX Series switches include a factory default configuration that enables interfaces with the link settings provided in Table 8.

Table 8: Factory Default Configuration Link Settings for EX Series Switches

Ethernet Interface

Autonegotiation

Flow Control

Link Mode

Link Speed

1 gigabit

Enabled

Enabled

Autonegotiation (full duplex or half duplex) For information about EX4300, see the Note below this table.

Autonegotiation (10 Mbps, 100 Mbps, or 1 Gbps)

10 gigabit (using a DAC cable)

Enabled

Enabled

Full duplex

10 Gbps

10 gigabit (using a fiber-optic cable)

Disabled

Enabled

Full duplex

10 Gbps

40 gigabit (using a DAC cable)

Enabled

Enabled

Full duplex

40 Gbps

40 gigabit (using a fiber-optic cable)

Disabled

Enabled

Full duplex

40 Gbps
Note:

On EX4300 switches, there is no link-mode configuration statement. The link-mode setting on an EX4300 switch is handled as follows:

  • If the link partner is operating in half duplex, the EX4300interface goes to half duplex.

  • If the link partner is not capable of autonegotiation, then the link is established as either half-duplex or full-duplex, based on the physical layer of the link partner and EX4300 switches. Only if the speed is either 10-Gbps or 100-Gbps and the duplexity is Half Duplex on both sides, link will be established successfully.

  • If the link partner is capable of autonegotiation and is operating in full duplex, the EX4300 interface also works in full duplex.

  • To force an EX4300 interface to stay in full-duplex mode, configure the interface’s speed as 10 Mbps or 100 Mbps and also configure the interface with the no-autonegotiation statement.

To configure the link mode and speed settings for a 1-Gigabit, 10-Gigabit, or 40-Gigabit Ethernet interface:

Note:

On EX4300 switches, there is no link-mode configuration statement. See information earlier in this document regarding how the link mode is set on EX4300 switches.

To configure additional link settings for a 1-Gigabit, 10-Gigabit, or 40-Gigabit Ethernet interface:

For detailed information about the FPC, PIC, and port numbers used for EX Series switches, see Understanding Interface Naming Conventions.

Configurable link settings include:

  • 802.3ad—Specify an aggregated Ethernet bundle. See Configuring Aggregated Ethernet Links (CLI Procedure).

  • auto-negotiation—Enable or disable autonegotiation of flow control, link mode, and speed.

    Note:

    Starting with Junos OS Releases 14.1X53-D40, 15.1R4, and 17.1R1, half-duplex communication is supported on all built-in network copper ports on EX4300 switches. Half-duplex is bidirectional communication; however, signals can flow in only one direction at a time. Full-duplex communication means that both ends of the communication can send and receive signals at the same time.

    Half-duplex is configured by default on EX4300switches. If the link partner is set to autonegotiate the link, then the link is autonegotiated to full duplex or half duplex. If the link is not set to autonegotiation, then the EX4300link defaults to half duplex unless the interface is explicitly configured for full duplex.

    To explicitly configure full duplex:

    To verify a half-duplex (or a full-duplex) setting:

  • flow-control—Enable or disable flow control.

  • link-mode—Specify full duplex, half duplex, or autonegotiation.

    Note:

    On EX4300 switches, there is no link-mode configuration statement. See information earlier in this document regarding how the link mode is set on EX4300 switches.

  • loopback—Enable or disable loopback mode.

  • speed—Specify 10 Mbps, 100 Mbps, 1 Gbps, or autonegotiation.

Configuring the IP Options

To specify an IP address for the logical unit using IPv4:

To specify an IP address for the logical unit using IPv6:

Note:

Access interfaces on EX4300 switches are set to family ethernet-switching by default. You might have to delete this or any other user-configured family setting before changing the setting to family inet or family inet6.

See Also

Configuring Gigabit and 10-Gigabit Ethernet Interfaces for OCX Series Switches

Devices include a factory default configuration that:

  • Enables all 10-Gigabit Ethernet network interfaces on the switch

  • Sets default link settings

  • Specifies a logical unit (unit 0) and assigns it to family ethernet-switching

  • Configures Storm Control on all 10-Gigabit Ethernet network interfaces

This topic describes:

Configuring the Link Settings for Gigabit Ethernet and 10-Gigabit Ethernet Interfaces

Devices include a factory default configuration that enables 10-Gigabit Ethernet and interfaces with applicable link settings.

The following default configurations are available on 10-Gigabit Ethernet interfaces:

  • The speed for 10-Gigabit Ethernet interfaces is set to 10 Gbps by default. The speed cannot be configured.

  • 10-Gigabit Ethernet interfaces operate in full-duplex mode by default.

  • Autonegotiation is not supported.

The ether-options statement enables you to modify the following options:

  • 802.3ad—Specify an aggregated Ethernet bundle for 10-Gigabit Ethernet interfaces.

  • loopback—Enable or disable a loopback interface for 10-Gigabit Ethernet interfaces.

To set ether-options for 10-Gigabit Ethernet interfaces:

Configuring the IP Options

To specify an IP address for the logical unit:

See Also

Release History Table
Release
Description
19.1R1
The 4-port 1-Gigabit Ethernet/10-Gigabit Ethernet uplink module (EX-UM-4SFPP-MR) on EX4300-48MP switches supports 1-Gbps speed.
18.2R1
The mge interface is a rate-selectable (multirate) Gigabit Ethernet interface that support speeds of 10-Gbps, 5-Gbps, and 2.5-Gbps over CAT5e/CAT6/CAT6a cables. In the EX2300, the mge interface supports 100-Mbps, 1-Gbps, and 2.5-Gbps speeds. Note that 10 Mbps speed is supported only on ge interfaces of EX2300 switch.
14.1X53-40
Starting with Junos OS Releases 14.1X53-D40, 15.1R4, and 17.1R1, half-duplex communication is supported on all built-in network copper ports on EX4300 switches.