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subnet-address (Easy EVPN LAG Configuration)

Syntax

Hierarchy Level

Description

Specify IRB instance subnet address parameters as part of a generated Ethernet VPN (EVPN) fabric configuration.

You use statements at the [edit services evpn] hierarchy level to simplify configuring an EVPN fabric with Ethernet segment identifier (ESI) link aggregation groups (LAGs) in the topology. The feature you enable with statements in this hierarchy is an easy EVPN LAG configuration feature, also called EZ-LAG.

You only need to configure a few statements to provide the parameters required for an EVPN core fabric with multihomed or single-homed customer edge (CE) devices (or end server devices). When you commit the [edit services evpn] configuration statements, the device uses a commit script to generate the corresponding standard EVPN fabric configuration statements.

The commit script uses the parameters you specify at the [edit services evpn evpn-vxlan irb irb-instance subnet-address] hierarchy level to generate IPv4 and/or IPv6 address configurations for an IRB instance as follows:

  • IRB interface subnet address.

    Note:

    For IPv6 data traffic, you can configure a global IPv6 address and an IPv6 link-local address for the IRB interface.

  • Virtual gateway address

Note:

By default, the commit script sets the virtual gateway MAC address for the device (which applies to all IRB instances) as follows:

  • IPv4 virtual gateway MAC address—00:00:5e:00:01:01

  • IPv6 virtual gateway MAC address—00:00:5e:00:02:01

You can override the default virtual gateway MAC addresses using the following options at the [edit services evpn global-parameters] hierarchy level:

  • virtual-gateway (v4-mac | v6-mac) virtual-gateway-mac-address—To set different virtual gateway MAC addresses for IPv4 traffic or IPv6 traffic

  • virtual-gateway-mac virtual-gateway-mac-address—To set the same virtual gateway MAC address for both IPv4 traffic and IPv6 traffic.

Starting in Junos OS and Junos OS Evolved Release 23.4R1, with the subnet-address inet and subnet-address inet6 options, you can specify multiple IRB subnet addresses using a list syntax [ addr1addr2 …]. You can still use the original syntax with a single subnet address (no list brackets), and use multiple statements with single subnet addresses to specify multiple IRB addresses.

Also as of those releases, in the generated configuration, the commit script includes router-advertisement statements at the [edit protocols] hierarchy level as follows to configure the device with default values to send router advertisement packets for a configured EZ-LAG IRB instance:

  • With an anycast gateway EZ-LAG configuration:

  • With a virtual gateway address EZ-LAG configuration:

Options

inet address(es)

Specify an IPv4 subnet address or multiple IPv4 subnet addresses for the IRB interface—you can specify a single address value ipv4-subnet-addr or an address list [ ipv4-subnet-addr1 ipv4-subnet-addr2 … ].

You must configure this option or the inet6 option (or both options).

inet6 address(es)

Specify an IPv6 subnet address or multiple IPv6 subnet addresses for the IRB interface—you can specify a single address value ipv6-subnet-addr or an address list [ ipv6-subnet-addr1 ipv6-subnet-addr2 … ].

You must configure this option or the inet option (or both options).

For IPv6 data traffic on an IRB interface, you can use either multiple statements with single addresses or one statement with an address list to specify the IPv6 global subnet address and the IPv6 link-local address (prefix fe80::) of the IRB interface. For example, if you include the following statements for an IRB interface IPv6 subnet address and an IPv6 link-local address for logical unit 10 in your EZ-LAG configuration:

or:

then the commit script adds the following statements in the generated configuration:

The commit script also includes default router-advertisement statements in the generated configuration for that IRB interface. For example, if you have an EZ-LAG virtual gateway configuration, the generated configuration also includes the virtual-router-only option, which enables sending router advertisement packets only for the link-local virtual gateway address:

See Routing IPv6 Data Traffic through an EVPN-VXLAN Network with an IPv4 Underlay and IPv6 Neighbor Discovery for more on EVPN-VXLAN IPv6 data traffic and setting IPv6 link-local addresses.
no-irb-address-auto-derive

Instruct the commit script to not derive IRB interface subnet addresses in the generated configuration for this IRB instance.

For configuration simplicity, with this feature you can set the same IRB interface subnet address on connected PE devices using this subnet-address option at the [edit services evpn evpn-vxlan irb irb-instance] hierarchy level. By default, the commit script derives different device IRB subnet addresses from the subnet-address value you configure for peer ID 1, based on the peer ID of the device on which it's running.

When you set no-irb-address-auto-derive, instead of the default behavior, the commit script uses exactly the IPv4 or IPv6 subnet addresses you specify with the subnet-address options on each device.

Note:

This option applies individually to the specified IRB instance.

You can alternatively set this option globally at the [edit services evpn global-parameters] hierarchy level. In that case, the option takes effect for all IRB instances on the device that you configure with the irb irb-instance statement at the [edit services evpn evpn-vxlan] hierarchy level.

If you don't set no-irb-address-auto-derive (either per IRB instance or globally), by default the commit script derives the subnet address based on the provided subnet-address value on each device. In this case, the commit process doesn't do a commit check to enforce setting the same subnet address across both devices.

Note:

We strongly recommend that you make sure you set subnet-address to the same base value on both peer PE devices in the easy EVPN LAG configuration. That way the default address derivation works as expected for the IRB interface subnet addresses on each peer PE device.

virtual-gateway-v4-address ipv4-virtual-gateway-address

Specify an IPv4 virtual gateway address for the IRB interface.

If you don't include this option to set a specific IPv4 virtual gateway address, the device derives a virtual gateway IPv4 address for the IRB interface from the address you specify with the inet option and the highest configurable IPv4 address in the subnet range.

For example, if you configure subnet address 10.1.1.1/24, the commit script generates IRB interface configuration statements with an IPv4 virtual gateway address 10.1.1.254.
virtual-gateway-v6-address ipv6-virtual-gateway-address

Specify an IPv6 virtual gateway address for the IRB interface.

If you don't include this option to set a specific IPv6 virtual gateway address, the device derives a virtual gateway IPv6 address for the IRB interface from the address you specify with the inet6 option and the highest configurable IPv6 address in the subnet range.

For example, if you configure subnet address 2001:db8::10:1:1:1/112 , the commit script generates IRB interface configuration statements with an IPv6 virtual gateway address 2001:db8::10:1:1:fffe.

Required Privilege Level

system—To view this statement in the configuration.

system-control—To add this statement to the configuration.

Release Information

Statement introduced in Junos OS Release 23.2R1 and Junos OS Evolved Release 23.2R1.

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