Routing IPv6 Data Traffic through an EVPN-VXLAN Network with an IPv4 Underlay
QFX10000 and QFX5110 switches can function as Layer 3 VXLAN gateways in an EVPN-VXLAN overlay network. Starting with Junos OS Release 15.1X53-D30 for QFX10000 switches and Junos OS Release 18.4R1 for QFX5110 switches, the IRB interfaces on these Layer 3 VXLAN gateways can route Layer 2 or 3 data packets from one IPv6 host to another IPv6 host through an EVPN-VXLAN network with an IPv4 underlay.
Upon receipt of a Layer 2 or 3 data packet from an IPv6 host, a Layer 3 VXLAN gateway encapsulates the packet with an IPv4 outer header, thereby tunneling the packet through the IPv4 underlay network. The Layer 2 or 3 VXLAN gateway at the other end of the tunnel de-encapsulates the packet and forwards the packet towards the other IPv6 host.
The Layer 3 VXLAN gateways in the EVPN-VXLAN overlay network learn the IPv6 routes through the exchange of EVPN Type-2 and Type-5 routes.
This feature is supported in EVPN-VXLAN overlay networks with the following architectures, which are commonly deployed within a data center:
EVPN-VXLAN centrally-routed bridging overlay (EVPN-VXLAN topology with a two-layer IPv4 fabric)—A two-layer IPv4 fabric in which QFX10000 or QFX5110 switches function as Layer 3 VXLAN gateways, and QFX5100 or QFX5200 switches function as Layer 2 VXLAN gateways. In this architecture, the IRB interfaces configured on the Layer 3 VXLAN gateways function in a central location in the fabric.
EVPN-VXLAN edge-routed bridging overlay (EVPN-VXLAN topology with a collapsed IPv4 fabric)—A one-layer IPv4 fabric in which QFX10000 or QFX5110 switches function as both Layer 2 and Layer 3 VXLAN gateways. In this architecture, the IRB interfaces configured on the Layer 3 VXLAN gateways function at the edge of the fabric.
This topic includes the following sections:
Benefits of Routing IPv6 Data Traffic through an EVPN-VXLAN Network With an IPv4 Underlay
Routing IPv6 data traffic through an EVPN-VXLAN network with an IPv4 underlay provides the following benefits:
Eliminates the need to deploy an IPv6 underlay network. The supported IPv4 fabric architectures are agile enough to support both IPv4 and IPv6 data traffic needs.
Leverages the EVPN control plane’s inherent support for exchanging IPv4 and IPv6 routes.
Does not introduce any new configuration. To set up this feature, you configure IRB interfaces with IPv6 addresses.
Centrally-Routed Bridging Overlay—How to Set Up the Routing of IPv6 Data Traffic
The focus of this section is the configuration of IRB interfaces on Layer 3 VXLAN gateways. For a more comprehensive example of configuring EVPN-VXLAN, see Example: Configure an EVPN-VXLAN Centrally-Routed Bridging Fabric.
The key to setting up this feature is the configuration of IRB interfaces on Layer 3 VXLAN gateways. In general, you configure the IRB interfaces as you would with only IPv4 hosts in the topology. However, in addition to specifying IPv4 addresses for the IRB interface and default Layer 3 gateway (virtual gateway), you also specify IPv6 addresses.
Table 1 shows how to configure the addresses for IRB interfaces irb.100 and irb.200 on the three Layer 3 VXLAN gateways. Table 2 outlines some additional required global configuration and configuration for irb.100 and irb.200.
Addresses |
Layer 3 VXLAN Gateway 1 |
Layer 3 VXLAN Gateway 2 |
Layer 3 VXLAN Gateway 3 |
Description |
---|---|---|---|---|
IRB interface irb.100 |
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IRB IPv4 address |
192.168.100.1/24 |
192.168.100.2/24 |
192.168.100.3/24 |
Specify a different IPv4 address for irb.100 on each device. |
IRB global IPv6 address |
2001:db8::192.168.100.1/96 |
2001:db8::192.168.100.2/96 |
2001:db8::192.168.100.3/96 |
Specify a different IPv6 address for irb.100 on each device. |
IRB link-local IPv6 address |
fe80::100:00:01/64 |
fe80::100:00:01/64 |
fe80::100:00:01/64 |
Specify the same link-local IPv6 address for irb.100 on each device. Any packet destined to this IPv6 address is intercepted for Network Discovery Protocol (NDP) processing. |
IRB link-local IPv6 address (DHCPv6 or SLAAC ) |
fe80::100:00:11/64 |
fe80::100:00:12/64 |
fe80::100:00:13/64 |
Specify a different link-local address on each device when using DHCPV6 or SLAAC in the EVPN Fabric. You must also configure the router advertisement for this IRB. |
Virtual gateway IPv4 address |
192.168.100.254/24 |
192.168.100.254/24 |
192.168.100.254/24 |
Specify the same IPv4 anycast address for the virtual gateway on each device. |
Virtual gateway IPv6 address |
2001:db8::192.168.100.254/96 |
2001:db8::192.168.100.254/96 |
2001:db8::192.168.100.254/96 |
Specify the same IPv6 anycast address for the virtual gateway on each device. |
Virtual gateway IPv6 address (DHCPv6 or SLAAC ) |
fe80::100:00:100 |
fe80::100:00:100 |
fe80::100:00:100 |
Specify the same virtual-gateway-address for the link-local address on all the devices when using DHCPV6 or SLAAC in the EVPN Fabric. You must also configure the router advertisement for this IRB. |
Virtual gateway IPv4 and IPv6 MAC addresses |
Method 1
Method 2
Method 3
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Method 1
Method 2
Method 3
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Method 1
Method 2
Method 3
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For the default Layer 3 gateway, the IPv4 and IPv6 MAC addresses can be the same or different, as long as they are consistent across the three devices. Here are the supported options:
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IRB interface irb.200 |
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IRB IPv4 address |
192.168.200.1/24 |
192.168.200.2/24 |
192.168.200.3/24 |
Specify a different IPv4 address for irb.200 on each device. |
IRB global IPv6 address |
2001:db8::192.168.200.1/96 |
2001:db8::192.168.200.2/96 |
2001:db8::192.168.200.3/96 |
Specify a different IPv6 address for irb.200 on each device. |
IRB link-local IPv6 address |
fe80::200:00:01/64 |
fe80::200:00:01/64 |
fe80::200:00:01/64 |
Specify the same link-local IPv6 address for irb.200 on each device. Any packet destined to this IPv6 address is intercepted for NDP processing. |
IRB link-local IPv6 address (DHCPv6 or SLAAC) |
fe80::200:00:11/64 |
fe80::200:00:12/64 |
fe80::200:00:13/64 |
Specify a different link-local address on each device when using DHCPV6 or SLAAC in the EVPN Fabric. You must also configure the router advertisement for this IRB. |
Virtual gateway IPv4 address |
192.168.200.254/24 |
192.168.200.254/24 |
192.168.200.254/24 |
Specify the same IPv4 anycast address for the virtual gateway on each device. |
Virtual gateway IPv6 address |
2001:db8::192.168.200.254/96 |
2001:db8::192.168.200.254/96 |
2001:db8::192.168.200.254/96 |
Specify the same IPv6 anycast address for the virtual gateway on each device. |
Virtual gateway IPv6 address (DHCPv6 or SLAAC) |
fe80::100:00:200 |
fe80::100:00:200 |
fe80::100:00:200 |
Specify the same virtual-gateway-address for the link-local address on all the devices when using DHCPV6 or SLAAC in the EVPN Fabric. You must also configure the router advertisement for this IRB. |
Virtual gateway IPv4 and IPv6 MAC addresses |
Method 1
Method 2
Method 3
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Method 1
Method 2
Method 3
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Method 1
Method 2
Method 3
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For the default Layer 3 gateway, the IPv4 and IPv6 MAC addresses can be the same or different, as long as they are consistent across the three devices. Here are the supported options:
|
Description |
Layer 3 VXLAN Gateway 1 |
Layer 3 VXLAN Gateway 2 |
Layer 3 VXLAN Gateway 3 |
---|---|---|---|
Global IRB interface configuration |
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Specify that the IPv4 and IPv6 MAC addresses of the default Layer 3 gateway are advertised to the Layer 2 VXLAN gateways without the extended community option. |
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IRB interface irb.100 configuration |
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Configure the Layer 3 VXLAN gateway to advertise the MAC and IP routes (MAC+IP type 2 routes) on behalf of the Layer 2 VXLAN gateways. |
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Enable the default Layer 3 gateway to be pinged by either IPv4 or IPv6 addresses. |
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IRB interface irb.200 configuration |
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Configure the Layer 3 VXLAN gateway to advertise the MAC and IP routes (MAC+IP type 2 routes) on behalf of the Layer 2 VXLAN gateways. |
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Enable the default Layer 3 gateway to be pinged by either IPv4 or IPv6 addresses. |
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DHCPv6 or SLAAC configuration |
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Configure the link-local address. |
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Configure the global address. |
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Configure the gateway to send router advertisement packets only for the link-local virtual-gateway-address. |
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Edge-Routed Bridging Overlay—How to Set Up the Routing of IPv6 Data Traffic
The focus of this section is the configuration of IRB interfaces on Layer 3 VXLAN gateways. For a more comprehensive example of configuring EVPN-VXLAN, see Example: Configuring an EVPN-VXLAN Edge-Routed Bridging Fabric with an Anycast Gateway.
The key to setting up this feature is the configuration of IRB interfaces on Layer 3 VXLAN gateways. In general, you configure the IRB interfaces as you would with only IPv4 hosts in the topology. However, in addition to specifying IPv4 addresses for the IRB interface, you also specify IPv6 addresses. You must also configure a MAC address for the IRB interface.
Table 3 shows how to configure the addresses for IRB interfaces irb.100 and irb.200 on the three Layer 3 VXLAN gateways. Table 4 outlines some additional required global IRB interface configuration.
Addresses |
Layer 2 and 3 VXLAN Gateway 1 |
Layer 2 and 3 VXLAN Gateway 2 |
Layer 2 and 3 VXLAN Gateway 3 |
Description |
---|---|---|---|---|
IRB interface irb.100 |
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IPv4 address |
192.168.100.1/24 |
192.168.100.1/24 |
192.168.100.1/24 |
Specify the same IPv4 address for irb.100 on each device. |
Global IPv6 address |
2001:db8::192.168.100.1/96 |
2001:db8::192.168.100.1/96 |
2001:db8::192.168.100.1/96 |
Specify the same IPv6 address for irb.100 on each device. |
Link-local IPv6 address |
fe80::100:00:01/64 |
fe80::100:00:01/64 |
fe80::100:00:01/64 |
Specify the same link-local IPv6 address for irb.100 on each device. Any packet destined to this IPv6 address is intercepted for NDP processing. |
IRB link-local IPv6 address (DHCPv6 or SLAAC) |
fe80::100:00:11/64 |
fe80::100:00:12/64 |
fe80::100:00:13/64 |
Specify a different link-local address on each device when using DHCPV6 or SLAAC in the EVPN Fabric. You must also configure the router advertisement for this IRB. |
IRB MAC address |
10:00:00:00:00:fe |
10:00:00:00:00:fe |
10:00:00:00:00:fe |
Specify the same MAC address for irb.100 on each device. |
IRB interface irb.200 |
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IPv4 address |
192.168.200.1/24 |
192.168.200.1/24 |
192.168.200.1/24 |
Specify the same IPv4 address for irb.200 on each device. |
Global IPv6 address |
2001:db8::192.168.200.1/96 |
2001:db8::192.168.200.1/96 |
2001:db8::192.168.200.1/96 |
Specify the same IPv6 address for irb.200 on each device. |
Link-local IPv6 address |
fe80::200:00:01/64 |
fe80::200:00:01/64 |
fe80::200:00:01/64 |
Specify the same link-local IPv6 address for irb.200 on each device. Any packet destined to this IPv6 address is intercepted for NDP processing. |
IRB link-local IPv6 address (DHCPv6 or SLAAC) |
fe80::200:00:11/64 |
fe80::200:00:12/64 |
fe80::200:00:13/64 |
Specify a different link-local address on each device when using DHCPV6 or SLAAC in the EVPN Fabric. You must also configure the router advertisement for this IRB.. |
IRB MAC address |
10:00:00:00:00:ff |
10:00:00:00:00:ff |
10:00:00:00:00:ff |
Specify the same MAC address for irb.200 on each device. |
Description |
Layer 2 and 3 VXLAN Gateway 1 |
Layer 2 and 3 VXLAN Gateway 2 |
Layer 2 and 3 VXLAN Gateway 3 |
---|---|---|---|
Global IRB interface configuration |
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For IPv4 fabric 2, a default Layer 3 gateway is not configured. Therefore, you must disable the advertisement of a default Layer 3 gateway. |
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DHCPv6 or SLAAC configuration |
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Configure the link-local address. |
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Configure the global IPv6 address. |
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Configure the gateway to send router advertisement packets only for the link-local virtual-gateway-address. |
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