Arista vEOS is a virtual version of Arista EOS.
This lab is an experiment with VARP. VARP is meant to replace first hop router redundancy protocols like VRRP and HSRP. Unfortunately, those protocols are usually working in active/standby mode. VARP is an attempt to correct that by assigning each virtual router a MAC address shared by all the devices of the virtual router.
As this is the first time I am playing with Arista EOS, you should not rely on any configuration files for serious work.
You can download vEOS from Arista website. You need both
Aboot-veos-serial-x.x.x.iso and vEOS-x.xx.xx.vmdk. Convert the
last one with qemu-img to the qcow2 format:
qemu-img convert -O qcow2 vEOS-x.xx.xx.{vmdk,img}
Symlink them in images/ as Aboot-veos.iso and vEOS.img. You can
set them read-only for safety. We use COW to avoid any modification of
the original image.
Some commands to check that everything works as expected.
Check that OSPF is OK:
vEOS1#show ip ospf interface
Vlan4094 is up
Interface Address 192.0.2.1, VRF default, Area 0.0.0.0
Network Type Point-To-Point, Cost: 10
Transmit Delay is 1 sec, State P2P
No Designated Router on this network
No Backup Designated Router on this network
Timer intervals configured, Hello 10, Dead 40, Retransmit 5
Neighbor Count is 1
Vlan3 is up
Interface Address 198.51.100.2, VRF default, Area 0.0.0.0
Network Type Broadcast, Cost: 10
Transmit Delay is 1 sec, State DR, Priority 1
Designated Router is 203.0.113.1
No Backup Designated Router on this network
Timer intervals configured, Hello 10, Dead 40, Retransmit 5
Neighbor Count is 0
Vlan4 is up
Interface Address 203.0.113.1, VRF default, Area 0.0.0.0
Network Type Broadcast, Cost: 10
Transmit Delay is 1 sec, State DR Other, Priority 1
Designated Router is 203.0.113.12
Backup Designated Router is 203.0.113.11
Timer intervals configured, Hello 10, Dead 40, Retransmit 5
Neighbor Count is 3
vEOS1#show ip ospf neighbor
Neighbor ID VRF Pri State Dead Time Address Interface
203.0.113.2 default 0 FULL 00:00:32 192.0.2.2 Vlan4094
203.0.113.2 default 1 2 WAYS/DROTHER 00:00:30 203.0.113.2 Vlan4
203.0.113.12 default 1 FULL/DR 00:00:39 203.0.113.12 Vlan4
203.0.113.11 default 1 FULL/BDR 00:00:39 203.0.113.11 Vlan4
Check the virtual IP is here:
vEOS1(config)#show ip virtual-router
IP virtual router is configured with MAC address: 001c.7300.0099
MAC address advertisement interval: 30 seconds
Interface IP Address Virtual IP Address Status Protocol
Vlan3 198.51.100.2/24 198.51.100.1 up up
Moreover, we can see its MAC address moving from one port to another:
/usr/bin/vde_switch: MAC 00:1c:73:00:00:99 moved from port 2 to port 1
/usr/bin/vde_switch: MAC 00:1c:73:00:00:99 moved from port 1 to port 2
/usr/bin/vde_switch: MAC 00:1c:73:00:00:99 moved from port 2 to port 1
/usr/bin/vde_switch: MAC 00:1c:73:00:00:99 moved from port 1 to port 2
/usr/bin/vde_switch: MAC 00:1c:73:00:00:99 moved from port 2 to port 1
/usr/bin/vde_switch: MAC 00:1c:73:00:00:99 moved from port 1 to port 2
And we can see on C2 that the virtual MAC is never used as a source address:
23:25:57.451429 50:54:58:5c:b4:7b > 50:54:93:35:24:50, ethertype IPv4 (0x0800), length 98: 203.0.113.11 > 198.51.100.12: ICMP echo request, id 238, seq 7, length 64
23:25:57.451447 50:54:93:35:24:50 > 00:1c:73:00:00:99, ethertype IPv4 (0x0800), length 98: 198.51.100.12 > 203.0.113.11: ICMP echo reply, id 238, seq 7, length 64
You should also see gratuitous ARP requests every 5 seconds (unless there are regular ARP requests in the same timeframe). This also means that it can take up to 5 seconds to recover from a failure.