The LANCOM 1781VA-4G has a built-in cellular module with two SIM-card slots and therefore has the option of installing an additional mobile connection on the same radio module (3G or 4G). This is useful for the case that, for example, the first (primary) mobile connection has a fault, cannot be used, or is restricted by volume limits.
This document describes how you can configure a backup of a mobile connection on the LANCOM 1781VA-4G using a second mobile connection.
1) Configuring the first mobile network connection with the Setup Wizard:
1.1) Open the Setup Wizard in LANconfig and select the option Set up Internet access.
1.2) Select the option Create a new connection for IPv4.
1.3) For the interface, select Mobile interface (internal modem).
1.4) Select your country in the following dialog.
1.5) The first (primary) mobile connection in this example uses the provider T-Mobile.
1.6) The SIM card of the provider T-Mobile is located in the upper card slot SIM 1 of the LANCOM 1781VA-4G.
1.7) Do not accept the default settings for the connection name but do enter a unique name for the mobile connection (in this case: T-MOBILE).
1.8) Enter the PIN for your mobile connection if the SIM card requires it.
1.9) Accept the Short hold time as the default value of 9,999 seconds.
1.10) Click on Finish to close the Setup Wizard and write the configuration back to the LANCOM 1781VA-4G.
1.12) Once the configuration is stored the mobile connection is established to the provider T-Mobile.
2) Configuring the second mobile connection with the Setup Wizard:
2.1) Re-open the Setup Wizard in LANconfig and select the option Set up Internet access.
2.2) Complete the same configuration steps as you did for the first mobile connection.
You need to enter different parameters in the dialogs shown below:
2.3) The second mobile connection should be made with the provider Vodafone.
2.4) The SIM card of the provider Vodafone is located in the lower SIM 2 card slot of the LANCOM 1781VA-4G.
2.5) Do not accept the default settings for the connection name but do enter a unique name for the mobile connection (in this case: VODAFONE).
2.6) Leave the setting for the default route unchanged.
2.7) At the end of the Setup Wizard click on Finish to save the configuration of the second mobile connection on the LANCOM 1781VA-4G.
Since the LANCOM 1781VA-4G has just one 3G/4G cellular module, the second mobile connection is not established after saving the configuration as the cellular module is already occupied with the first mobile connection.
3) Configuring the backup function in case of downtime/fault of the first (primary) mobile connection:
3.1) Open the configuration of the LANCOM 1781VA-4G in LANconfig and switch to the menu item Interfaces -> WAN -> Interface settings -> V.24/Mobile.
3.2) Ensure that the field Mobile profile is empty.
3.3) Open the configuration of the LANCOM 1781VA-4G in LANconfig and switch to the menu item Communication -> Call management -> Backup table.
3.4) Add a new entry to the Backup table:
- As the Remote site you select the first mobile connection T-MOBILE.
- The second mobile connection VODAFONE is entered in the field Backup list
- For the option Begin with enter the setting for the last successfully reached remote site
- In this example, the Maximum backup time is set to 3 minutes
For backup scenarios via a cellular connection (multi-SIM), where for technical reasons the cellular module can only establish one connection at a time, it is only the termination of the backup state that triggers the main connection to attempt to reconnect.
3.5) Write the configuration back to the LANCOM 1781VA-4G. This concludes the configuration.
4) Configuring the backup function on reaching a maximum volume budget on the first mobile connection:
4.1) Open the configuration of the LANCOM 1781VA-4G in LANconfig and switch to the menu item Interfaces -> WAN -> Interface settings -> V.24/Mobile.
4.2) Ensure that the field Mobile profile is empty.
4.3) Complete the configuration steps 3.3) and 3.4).
4.4) Open the menu item Management -> Budget -> Volume budgets.
4.5) In this configuration example the data transfer speed of the first mobile connection is throttled when the volume budget of 1 GB is reached, in which case we should switch to the second mobile connection.
- Select the entry for the first mobile connection (in this case: T-MOBILE).
- In the field Budget enter the value 1024 Megabytes and select the action Disconnect.
4.6) Write the configuration back to the LANCOM 1781VA-4G. This concludes the configuration.
The router will not connect to the first (primary) mobile connection until the next accounting period or if the budget counter is reset manually. The second mobile connection remains functional in the meantime.
The budget recorded by the LANCOM 1781VA-4G can be manually reset in WEBconfig (
LCOS Menu Tree -> Setup -> Charges
-> Reset-Budgets ).