NBB-800
User Manual for NRSW version 4.5.0.100
In general, a link will be only dialed or declared as up if the following prerequisites are met:
Condition
WWAN
WLAN
ETH
PPPoE
Modem is registered
X
Registered with valid service type
X
Valid SIM state
X
Sufficient signal strength
X
X
Client is associated
X
Client is authenticated
X
Valid DHCP address retrieved
X
X
X
X
Link is up and holds address
X
X
X
X
Ping check succeeded
X
X
X
X
The menu can be used further to prioritize your WAN links. The highest priority link which has been
established successfully will become the so-called
hotlink
which holds the default route for outgoing
packets.
In case a link goes down, the system will automatically switch over to the next link in the priority list.
You can configure each link to be either established when the switch occurs or permanently in order to
minimize link downtime.
Parameter
WAN Link Priorities
1st priority
The primary link which will be used whenever possible.
2nd priority
The first fallback link, it can be enabled permanently or being dialed
as soon as Link 1 goes down.
3rd priority
The second fallback link, it can be enabled permanently or being di-
aled as soon as Link 2 goes down.
4th priority
The third fallback link, it can be enabled permanently or being dialed
as soon as Link 3 goes down.
Links are being triggered periodically and put to sleep in case it was not possible to establish them
within a certain amount of time. Hence it might happen that permanent links will be dialed in back-
ground and replace links with lower priority again as soon as they got established. In case of interfering
links sharing the same resources (for instance in dual-SIM operation) you may define a switch-back
interval after which an active hotlink is forced to go down in order to let the higher-prio link getting
dialed again.
We recommend to use the
permanent
operation mode for WAN links in general. However, in case
of time-limited mobile tariffs for instance, the
switchover
mode might be applicable. By using the
distributed
mode, it is possible to distribute outgoing traffic over multiple WAN links based on their
weight ratio.
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