lte dhcp stopped no reconnect

RouterOS Wireless Networking
1

Hi there,

i have a problem with my lte connection.
RB921UAG (mipsbe) with v6.40.5 and Firmware 3.41

the huawei device is registered and the interface is running, but it doesn´t get a dhcp address from the dhcp client.
The status is dhcp stopped and red and doesn´t retry for getting an address.
Release and Renew doesn´t work.
I have to deactivate and enable lte interface once so the dhcp client is searching for an address again
RSSI and ASU is good

that´s a huge problem because the routers are in the field and with no vpn connection we can´t reconfigure it without approaching the station

thanks for help!

2

no ideas? :frowning:

3

Well, it is not a “solution”, but it works for a while:

You can set a timer or a watchdog, that at a certain time or event (like no ping to internet anymore), the LTE interface goes down for 1 minute, and then up.

4

thanks for your advice

that´s what i already done, but doesn´t work either the most time

in my opinion it´s about the sw upgrade and the sierra mc7710 firmware…
but didn´t find a solution yet even with different versions…
im freakin out… :frowning:

5

Is that a LTE interface connected to USB port?
It is not very reliable. Some topics about that already, join in there instead of starting new topic.

6

no it´s MiniPCIe

i found some posts, but there´s also no solution…

7

Ok I would not have guessed it also affects those cards (I have no experience with them).
My guess has always been that it is caused by drawing too much current from USB when the transmit power is at its highest.
This is backed by the fact that it usually goes down when doing lots of data transfer, and only when there is poor coverage.
At places with good coverage (so the transmit power is low) it seems to be working fine.
Maybe there is a similar issue with PCIe. Try to connect a better antenna or move the setup to a location with good coverage
and see if that fixes it.

8

i tried 4 Antennas until now, industrial standard
coverage is perfect, i have good rssi and asu values
also different providers
data transfer is very less, just a few mb a day

it drives me crazy

9

that´s all i got from log

09:28:54 lte,async,raw lte1: sent AT+CSQ 
09:28:54 lte,async,raw lte1: rcvd +CSQ: 27,99 
09:28:57 lte,async,raw lte1: sent AT+CSQ 
09:28:57 lte,async,raw lte1: rcvd +CSQ: 27,99 
09:29:00 lte,async,raw lte1: sent AT+CSQ 
09:29:00 lte,async,raw lte1: rcvd +CSQ: 27,99 
09:29:02 ovpn,info ovpn-dfue-ef: initializing... 
09:29:02 ovpn,info ovpn-dfue-ef: connecting... 
09:29:02 ovpn,debug ovpn-dfue-ef: disconnected <could not resolve name> 
09:29:02 ovpn,info ovpn-dfue-ef: terminating... - could not resolve name 
09:29:02 ovpn,info ovpn-dfue-ef: disconnected
10

I can understand that! Fortunately, for me 4G is only used for backup links.

11

I know how frustrating it can be.

That is why I took a separate LTE modem (I cannot wait until Mikrotik comes with a LTE ready device (announced in I think summer 2017, still not here)). That is why I purchased a Teltonika LTE modem. It is a LTE modem with a WAN, LAN and WiFi ports / antenna’s.
It is based on Linux, and it can also do OSPF etc…

That modem is also used in mission critical situation in professional systems, like in tunnels, and other underground places.

https://www.eurodk.com/en/products/3g-4g-routers/teltonika-rut240-lte-router-eu-ver

12

thanks for the advice

sounds interresting, but we have already finished the project with about 350 Mikrotik Routerboards and Sierra LTE Modules in a wide area :confused:
worked fine in the beginning but now we have more and more trouble with the described problems and DHCP loss :frowning: