Looking for a guide how to get started with LTE on Mervis IDE? Please see this tutorial, otherwise continue here.
Axon
Axon series units are shipped with the Mervis image by default. Mervis can be disabled or you can flash the open-source image manually.
This manual refers to the LTE series of Axon units (currently S165, M565 and M265).
sudo su apt-get update apt-get install unipi-lte
internet
is the default value. By default, the unipi-lte Linux service provides automatic handling with the default network gateway according to the WAN availability on both main and backup network interfaces. The main network adapter is usually wired ethernet (eth0) while the backup is realized by the LTE modem. In the Linux routing table, the default GW routes for both of these interfaces should be always present. When a “swap” of these interfaces is necessary, the unipi-lte daemon automatically increases/decreases their metrics.
Therefore, it is necessary to continually keep the metrics as positive non-zero values. This is ensured by a DHCP client when DHCP is active on the main network interface but it must be assured manually if static IP is configured on the main interface (as static routes have zero metrics as default). As an example, you can put a constant to the interface’s configuration file at /etw/network/interfaces.d.
Then, the /etc/network/interfaces.d/eth0 file for static IP configuration may look like:
# Example static IP configuration for unit belonging to LAN auto eth0 iface eth0 inet static address 192.168.221.188 gateway 192.168.221.1 netmask 255.255.255.0 dns-nameservers 192.168.221.1 metric 5 # A positive non-zero constant
The auto-switch feature can be disabled in the daemon’s config file.
An additional feature auto_keepon should help if the LTE network interface is turned off accidentally (e.g. caused by ifdown command). In such a case, the re-enable (UP) operation is performed on that interface and also routing table records are refreshed. The feature is enabled by default and can be disabled in the configuration file.
LED | OFF | ON | Flashing |
---|---|---|---|
SIM | LTE linux service (daemon) is not active (disabled or not installed) | SIM is OK | Slow — No sim inserted (or SIM corrupted) Fast — wrong PIN |
NET | Deregistered from network | Registered to network | - |
SIG | No signal | Excellent signal | Signal quality — faster ∼ better |
INT | No WAN access | Unit online, backup active (or single interface only) | Slow — connected via the main WAN interface, backup inactive Fast — connected via backup WAN interface |
All LEDs flashing — LTE module is restarting.