LtAP mini LTE kit (2024)

The LtAP mini LTE kit (2024) carries the product code RB912R-2nD-LTm&EC200A-EU. It is the small LtAP: one modem, one radio on 2.4 GHz and one ethernet port. It belongs where there is no fixed line, or where nobody visits often: a boat, a camper, a site hut, a roadside cabinet, a holiday cottage.

The catalogue records the default configuration router-lte with lte1 as the WAN interface. Everything you fill in about your internet connection therefore concerns the SIM.

Two catalogue figures decide a lot here: the port is 100 Mbit and there is 64 MB of memory. At 64 MB the configurator raises its small-board warning.

The port and the modem

• lte1: the modem, your WAN by default. This is where the APN goes, and any credentials your carrier asks for.
• ether1: one 100 Mbit port, with PoE-in. Usually your LAN port, towards a switch or a single device. Because the port takes PoE-in you can feed the box over that same cable, which is handy on a mast or in a cabinet.

There is no PoE-out: the catalogue records no feeding port, so the PoE-out per port field never appears. See PoE-out per port for the difference between powering and being powered.

One wired port means Office router with VLANs, Router + CAPsMAN and Hotspot are greyed out with "Needs at least 3 wired ports (WAN + LAN + trunk)". If more devices need a cable, put a switch behind ether1. You can also use ether1 as a second uplink when a cable is temporarily available; see Multiple uplinks. Nothing wired is then left.

The radio

One radio, wlan1, on 2.4 GHz. No 5 GHz. For this kind of place that is often right: range matters more than speed, and the mobile line is the narrowest link anyway. Pick a narrow channel; width buys you nothing on 2.4 GHz. See Channels, width and power.

The Wi-Fi package is wireless, the older of the two in RouterOS v7, so the script writes /interface wireless. No WPA3, no 802.11r. Pick WPA3 and the tool sets the SSID up as WPA2-PSK with AES and says so. The catalogue records no Wi-Fi generation for this model. See Setting up Wi-Fi.

What is inside

From the catalogue: MIPSBE, 64 MB of memory and licence level 4. A switch chip is not recorded for this model in our catalogue, so we do not name one. hw_vlan is empty, so the warning about bridge VLAN filtering and hardware offload does not appear here.

At 64 MB the small-board warning does appear: keep the configuration small, do not install packages you are not using, and check what is free with /system resource print. See also RouterOS licences for what level 4 means.

What it is good at, and where it runs out

Good at: delivering internet where no cable reaches, with a firewall, DHCP and a bit of Wi-Fi in the same box. As a backup line behind a fixed connection it works too, see Recipe: LTE as a backup line.

Where it runs out:

• One 100 Mbit port. That is the wired side of this device, and its ceiling.
• One 2.4 GHz radio. A few phones and a laptop, no more.
• 64 MB. No hotspot, no containers.
• Carrier-grade NAT. Port forwarding and inbound VPN usually do not work; build an outbound tunnel. See WireGuard and Site-to-site tunnels.

Which roles fit

• LTE / 5G router: the role this device exists for.
• Home router: when you do want ether1 as the WAN.
• Access point and CAP (managed by CAPsMAN): everything bridged behind another router.
• Wireless CPE / point-to-point and Wi-Fi repeater: possible, but with one 2.4 GHz radio rarely the best choice.
• VPN gateway: available; a tunnel built outwards from here works behind CGNAT as well.
• Harden only (baseline): for an LtAP mini that is already running.

The quickest route to a working configuration

1. Pick One device and search for LtAP mini or RB912R.
2. Pick the LTE / 5G router role.
3. Fill in the APN; leave the default route and the carrier's DNS switched on.
4. Set up the LAN, set the country and one SSID, set an admin password.
5. Reset the device and paste the script. See Using the script.

Afterwards check with /interface lte print and /ip address print that the modem is connected. No address on lte1? See LTE does not connect.

What trips people up

• The wrong APN. The most reported fault on every LTE model.
• Confusing the big LtAP with this one. The LtAP LTE6 kit is a different device; this mini has one 100 Mbit port.
• Forgetting the power. The port takes PoE-in, so the injector or switch at the far end has to supply it.
• Port forwarding that does not work. Usually CGNAT, not your firewall; see Opening a port.
• Letting memory fill up. At 64 MB every section you switch on counts.