Allied Telesis AT-WR4500 - Manual (Page 250)

250 AT-WR4500 Series - IEEE 802.11abgh Outdoor Wireless Routers
RouterOS v3 Configuration and User Guide
other configuration) active. A backup instance is not 'running', so all the settings attached to that interface
is inactive.
Property Description
arp (disabled | enabled | proxy-arp | reply-only; default: enabled) - Address Resolution Protocol
authentication (none | simple | ah; default: none) - authentication method to use for VRRP
advertisement packets
none - no authentication
simple - plain text authentication
ah - Authentication Header using HMAC-MD5-96 algorithm
backup (read-only: flag) - whether the instance is in the backup state
interface (name) - interface name the instance is running on
interval (integer: 1..255; default: 1) - VRRP update interval in seconds. Defines how frequently the master
of the given cluster sends VRRP advertisement packets
mac-address (MAC address) - MAC address of the VRRP instance. According to the RFC, any VRRP
instance should have its unique MAC address
master (read-only: flag) - whether the instance is in the master state
mtu (integer; default: 1500) - Maximum Transmission Unit
name (name) - assigned name of the VRRP instance
on-backup (name; default: "") - script to execute when the node switch to backup state
on-master (name; default: "") - script to execute when the node switch to master state
password (text; default: "") - password required for authentication depending on method used can be
ignored (if no authentication used), 8-character long text string (for plain-text authentication) or 16-
character long text string (128-bit key required for AH authentication)
preemption-mode (yes | no; default: yes) - whether preemption mode is enabled
no - a backup node will not be elected to be a master until the current master fail even if the backup
node has higher priority than the current master
yes - the master node always has the priority
priority (integer: 1..255; default: 100) - priority of the current node (higher values mean higher priority)
255 - RFC requires that the router that owns the IP addresses assigned to this instance had the priority
of 255
vrid (integer: 0..255; default: 1) - Virtual Router Identifier (must be unique on one interface)
All the nodes of one cluster must have the same vrid, interval, preemption-mode, authentication
and password.
To add a VRRP instance on ether1 interface, forming (because priority is 255) a virtual router with
vrid of 1:
[admin@AT-WR4562] ip vrrp> add interface=ether1 vrid=1 priority=255
[admin@AT-WR4562] ip vrrp> print
Flags: X - disabled, I - invalid, M - master, B - backup
0 I name="vr1" interface=ether1 vrid=1 priority=255 interval=1
preemption-mode=yes authentication=none password="" on-backup=""
on-master=""
[admin@AT-WR4562] ip vrrp>
Note that the instance is active at once. This is because it has the priority of 255. The instance would
wait in backup mode for a new master election process to complete in its favour before assuming the
master role otherwise. This also means that there must not be other VRRP routers with the maximal
priority