Overview

Arista EOS (Extensible Operating System) is the network operating system for Arista switches. SiteRM controls these devices using the sense.aristaeos Ansible collection. Arista EOS supports VLAN creation and hardware-level QoS but does not support BGP control through SENSE.

Property Value
Ansible network_os sense.aristaeos.aristaeos
Ansible Collection sense-aristaeos-collection
VLAN Creation Yes
BGP Control No
BGP Multipath No
QoS (network-level) Yes
Ping / Traceroute Yes

Ansible Inventory Configuration

inventory:
  aristaeos_s0:
    network_os: sense.aristaeos.aristaeos
    host: 192.168.1.10
    user: admin
    pass: <password>            # or use sshkey
    # sshkey: /opt/siterm/config/ssh-keys/id-rsa-sense
    become: false
    ssh_common_args: "-o StrictHostKeyChecking=no"
    snmp_params:
      session_vars:
        community: public
        hostname: 192.168.1.10
        version: 2

Facts Collection

SiteRM executes the following commands to collect topology and interface information from Arista EOS devices:

show version | json
show running-config
show interfaces | json
show lldp neighbors detail | json
show vlan | json
show interfaces switchport | json

For routing facts (if enabled):

show ip route vrf all | json
show ipv6 route vrf all | json

Information extracted:

  • System version and hardware platform
  • Interface details: description, MAC, MTU, bandwidth/speed, operational status, IPv4/IPv6 addresses, VRF assignments
  • VLAN memberships and switchport trunk/access assignments
  • LLDP neighbors: remote hostname, port, chassis ID — used for topology stitching
  • Running configuration: VRF definitions, port-channel configuration

VLAN Creation and Deletion

Create VLAN (example: VLAN 1798, VRF lhcone, ports Ethernet31/1 and Ethernet30/1)

# Create VLAN and L3 interface
vlan 1798
interface Vlan 1798
 description urn:ogf:network:service+8791cc78...:vt+l2-policy::Connection_1
 vrf lhcone
 ipv6 address fc00:0:0:0:0:0:0:16/124

# Add to trunk ports
interface Ethernet31/1
 switchport trunk allowed vlan add 1798
interface Ethernet30/1
 switchport trunk allowed vlan add 1798

Delete VLAN

no vlan 1798
no interface Vlan 1798

interface Ethernet31/1
 switchport trunk allowed vlan remove 1798
interface Ethernet30/1
 switchport trunk allowed vlan remove 1798

Note: On Arista EOS, deleting the VLAN does not automatically remove it from trunk ports. SiteRM explicitly issues switchport trunk allowed vlan remove for each port when deleting a VLAN.

QoS Configuration

Arista EOS supports hardware-level QoS through class-map and policy-map configurations. SENSE applies per-VLAN traffic policing using the SENSE_QOS policy map.

QoS Setup (example: VLAN 3616 on Ethernet12/1 and Port-Channel502, 50 Gbps guaranteed)

# Create VLAN class-map
class-map type qos match-any VLAN3616
 match vlan 3616
exit

# Apply policy (guaranteedCapped — fixed rate, no burst beyond limit)
policy-map type quality-of-service SENSE_QOS
 class VLAN3616
  set traffic-class 7
  police rate 50000 mbps burst-size 256 mbytes
 exit
exit

# Apply policy to interfaces
interface Ethernet12/1
 service-policy type qos input SENSE_QOS
interface Port-Channel502
 service-policy type qos input SENSE_QOS

QoS for softCapped and bestEffort

# softCapped — guaranteed up to min_rate, bursts up to max_rate
policy-map type quality-of-service SENSE_QOS
 class VLAN3616
  set traffic-class 4
  police rate 50000 mbps burst-size 256 mbytes action set drop-precedence rate 100000 mbps burst-size 256 mbytes
 exit
exit

# bestEffort — 100 Mbps minimum, up to remaining capacity
policy-map type quality-of-service SENSE_QOS
 class VLAN3616
  set traffic-class 2
  police rate 100 mbps burst-size 256 mbytes action set drop-precedence rate 100000 mbps burst-size 256 mbytes
 exit
exit

Remove QoS

no class-map type qos match-any VLAN3616

policy-map type quality-of-service SENSE_QOS
 no class VLAN3616
exit

Ping and Traceroute

SENSE can issue active probes from Arista EOS devices (requires IP assigned to a SENSE VLAN interface).

Ping

# IPv6 with VRF
ping vrf lhcone ipv6 fc00:0:0:0:0:0:0:17 timeout 5 repeat 10

# IPv6 without VRF
ping ipv6 fc00:0:0:0:0:0:0:17 timeout 5 repeat 10

# IPv4 with VRF
ping vrf lhcone ip 10.0.0.1 timeout 5 repeat 10

Note: Arista EOS uses the ipv6 / ip keyword after ping (unlike OS 9/10 which use ping6), and uses timeout + repeat keywords (not -c/-i flags).

Traceroute

# IPv6 with VRF
traceroute vrf lhcone ipv6 fc00:0:0:0:0:0:0:17

# IPv4 with VRF
traceroute vrf lhcone ip 10.0.0.1

Switch Configuration in main.yaml

aristaeos_s0:
  vlan_mtu: 9000
  rate_limit: true             # Enable per-port QoS
  vlan_range:
    - 3600-3699
  allports: false
  ports:
    Ethernet12/1:
      capacity: 100000         # Port capacity in Mbps
    Port-Channel502:
      capacity: 100000
      isAlias: urn:ogf:network:remote-site.net:2024:switch_s0:port_xyz
      wanlink: true

Known Limitations and Notes

  • No BGP control: Arista EOS does not support SENSE BGP control. Network routing to/from SENSE VLANs must be configured manually or via other automation tools.
  • QoS maximum policy rate: There is a platform-enforced maximum police rate. The max_policy_rate site configuration parameter can be used to cap the maximum rate applied per class. Refer to Arista documentation for per-platform limits.
  • QoS traffic classes: SENSE uses traffic classes 7 (guaranteedCapped), 4 (softCapped), and 2 (bestEffort). Ensure these classes are not already in use on the device.
  • LLDP: Required on trunk ports for automatic topology discovery. Without LLDP, all inter-switch links must be manually defined via isAlias.