Enable SIM-switch

config extender-controller extender
    edit <FEX SN>
        set authorized enable
        config modem1
            set ifname <fext-wan>
            config auto-switch
                set by-disconnect enable
                set by-signal disable
                set by-data-plan disable
                set disconnect-threshold 1
                set disconnect-period 600
                set switch-back by time by-timer set switch-back-by-time 00:01
                set switch-back-by-timer 3600
            end
        end
    next
end

SIM-switching can be configured by data plan, disconnect settings, signal strength, coupled with switch back by time or by timer. All these options are under the “Auto switch” setting.

Parameter	Description
by-disconnect	The SIM card switches when the active card gets disconnected according to the 'disconnect-threshold' and 'disconnect-period'.
by-signal	The SIM card switches when the signal strength gets weaker than the signal-threshold.
by-data-plan	The SIM card switches when 'capacity' is overrun and 'overage' is enabled.
disconnect-threshold	The number (1 - 100) of disconnects for SIM switch to take place.
disconnect-period	The evaluation period (600 - 18000) in seconds for SIM switch.
switch-back	Enables switching back to the preferred SIM card.
switch-back-by-time	Switches over to the preferred SIM /carrier at a specified (UTC) time (HH:MM).
switch-back-by-timer	Switches over to the preferred SIM/carrier after a given time (3600- 2147483647) in seconds.