IRB with Anycast Gateways « ipSpace.internet weblog

netlab launch 1.4 added help for static anycast gateways and VRRP. At the moment we’ll use that performance so as to add anycast gateways to the VLAN trunk lab:

We’ll begin with the VLAN trunk lab topology and make the next adjustments:

• We’ll rearrange the node checklist to ensure the switches get the bottom doable node ID:

nodes: [ s1, s2, h1, h2, h3, h4 ]

• The switches have to make use of the brand new gateway module:

teams:
switches:
members: [ s1, s2 ]
module: [ vlan, gateway ]
gadget: eos

• We’ve got to allow first-hop gateway on VLAN hyperlinks:

vlans:
crimson:
gateway: True
blue:
gateway: True

• The default FHRP protocol is anycast (we might additionally use VRRP), and the default shared IP deal with is the final IP deal with within the subnet. We’ll use the primary IP deal with within the subnet:

gateway.id: 1

After beginning the lab you’ll discover the change in node identifiers and interface IP addresses. With out the anycast gateway, netlab assigns node ID 1 (and loopback IP deal with 10.0.0.1) to S1. Now that the node ID 1 is reserved, S1 will get loopback deal with 10.0.0.2.

The one different change on the switches is the VLAN interface configuration – netlab configures ip deal with in addition to ip virtual-router deal with on EOS gadgets:

VLAN interface configuration on S1

interface Vlan1000
   description VLAN crimson (1000) -> [h1,s2,h2]
   ip deal with 172.16.0.2/24
   ip virtual-router deal with 172.16.0.1/24
!
interface Vlan1001
   description VLAN blue (1001) -> [h3,s2,h4]
   ip deal with 172.16.1.2/24
   ip virtual-router deal with 172.16.1.1/24
!
ip virtual-router mac-address 02:00:ca:fe:00:ff

Lastly, the static routes on Linux hosts use the anycast gateway IP deal with (the default route factors to the administration community):

Static routes on H1

h1:/# ip route
default through 192.168.121.1 dev eth0
10.0.0.0/24 through 172.16.0.1 dev eth1
10.1.0.0/16 through 172.16.0.1 dev eth1
10.2.0.0/24 through 172.16.0.1 dev eth1
172.16.0.0/24 dev eth1 scope hyperlink  src 172.16.0.4
172.16.0.0/16 through 172.16.0.1 dev eth1
192.168.121.0/24 dev eth0 scope hyperlink  src 192.168.121.104

Wish to run this lab by yourself, or strive it out with completely different gadgets? No drawback: