AT-WR4500 Series - IEEE 802.11abgh Outdoor Wireless Routers
155
RouterOS v3 Configuration and User Guide
Description
To provide a proper failover, you should specify
link-monitoring
parameter. It can be:
•
MII (Media Independent Interface) type1 or type2 - Media Independent Interface is an abstract layer
between the operating system and the NIC which detects whether the link is running (it performs
also other functions, but in our case this is the most important).
•
ARP - Address Resolution Protocol periodically (for
arp-interval
time) checks the link status.
link-monitoring
is used to check whether the link is up or not.
Property Description
arp
(disabled | enabled | proxy-arp | reply-only; default:
enabled
) - Address Resolution Protocol for the
interface
disabled
- the interface will not use ARP
enabled
- the interface will use ARP
proxy-arp
- the interface will use the ARP proxy feature
reply-only
- the interface will only reply to the requests originated to its own IP addresses. Neighbour
MAC addresses will be resolved using
/ip arp
statically set table only
arp-interval
(
time
; default:
00:00:00.100
) - time in milliseconds which defines how often to monitor
ARP requests
arp-ip-targets
(
IP address
; default:
""
) - IP target address which will be monitored if
link-monitoring
is
set to
arp
. You can specify multiple IP addresses, separated by comma
down-delay
(
time
; default:
00:00:00
) - if a link failure has been detected, bonding interface is disabled for
down-delay
time. Value should be a multiple of
mii-interval
lacp-rate
(1sec | 30secs; default:
30secs
) - Link Aggregation Control Protocol rate specifies how often
to exchange with LACPDUs between bonding peer. Used to determine whether link is up or other
changes have occured in the network. LACP tries to adapt to these changes providing failover.
link-monitoring
(arp | mii-type1 | mii-type2 | none; default:
none
) - method to use for monitoring the
link (whether it is up or down)
arp
- uses Address Resolution Protocol to determine whether the remote interface is reachable
mii-type1
- uses Media Independent Interface type1 to determine link status. Link status determenation
relies on the device driver. If bonding shows that the link status is up, when it should not be, then it
means that this card don't support this possibility.
mii-type2
- uses MII type2 to determine link status (used if
mii-type1
is not supported by the NIC)
none
- no method for link monitoring is used. If a link fails, it is not considered as down (but no traffic
passes through it, thus).
mac-address
(
read-only: MAC address
) - MAC address of the bonding interface
mii-interval
(
time
; default:
00:00:00.100
) - how often to monitor the link for failures (parameter used
only if
link-monitoring
is
mii-type1
or
mii-type2
)
mode
(802.3ad | active-backup | balance-alb | balance-rr | balance-tlb | balance-xor | broadcast; default:
balance-rr
) - interface bonding mode. Can be one of:
802.3ad
- IEEE 802.3ad dynamic link aggregation. In this mode, the interfaces are aggregated in a group
where each slave shares the same speed. If you use a switch between 2 bonding routers, be sure that this
switch supports IEEE 802.3ad standard. Provides fault tolerance and load balancing.
active-backup
- provides link backup. Only one slave can be active at a time. Another slave becomes
active only, if first one fails.
balance-alb
- adaptive load balancing. It includes
balance-tlb
and received traffic is also balanced.
Device driver should support for setting the mac address, then it is active. Otherwise
balance-alb
doesn't work. No special switch is required.
balance-rr
- round-robin load balancing. Slaves in bonding interface will transmit and receive data in
sequential order. Provides load balancing and fault tolerance.
balance-tlb
- Outgoing traffic is distributed according to the current load on each slave. Incoming traffic
is received by the current slave. If receiving slave fails, then another slave takes the MAC address of the
failed slave. Doesn't require any special switch support.
balance-xor
- Use XOR policy for transmit. Provides only failover (in very good quality), but not load
balancing, yet.
broadcast
- Broadcasts the same data on all interfaces at once. This provides fault tolerance but slows
down traffic throughput on some slow machines.
mtu
(
integer
: 68..1500; default:
1500
) - Maximum Transmit Unit in bytes