Cinterion ELS61-E2 network problems | Telit Cinterion IoT Developer Community
September 25, 2020 - 10:26am, 1272 views
Hi!
I have a weird network problem with a handful of new ELS61-E2 modules, which I recently bought to replace some older Coniugo modems.
My setup is as follows:
I have an SMS server running Windows Server 2012 R2, and a piece of software called "Diafaan SMS server"
This server connects to modems over LAN
Server and modems are on same network, same VLAN (10.129.x.x / VLAN1)
Server is working fine, SMS are beeing sent out, on both old Coniugo and new ELS61 modems.
I am in the process of replacing old SMS server with a new one, based on Windows Server 2019 and a newer version of Diafaan.
New setup is SMS server in VLAN51 (10.128.64.x), and modens still on VLAN1 / 10.129.x.x
There are full network connectivity. Modems can be ping'ed from server and vice versa.
Problems start when I try to connect the ELS61 modules to the new server.
I can add the module as a new gateway in Diafaan (connection tests OK), but in this process Diafaan server reboots the module, and then IP connection is lost.
Weird is, that connetion is only lost from the new server in VLAN51. I can still ping module from a server in VLAN1.
Even more weird is, that if I go into ELS61 configuration, and under Network / Static Routes try to add a route, then immediately deletes it and press Save & Apply, then network connectivity from VLAN51 is restored.
There are no static routes defined in the first place.
Modules are powered using PoE. Not sure if this has any signficance.
Firmware version is: OpenWrt 18.06.1 r7258-5eb055306f / LuCI openwrt-18.06 branch (git-18.228.31946-f64b152)
Kernel version is: 4.9.120
Hello,
In the LAN terminal there is a separate processor controlled by OpenWrt system and additionally ELS61-E module connected to OpenWrt over USB which is used as a modem.
I assume that the software restarts OpenWrt and then the terminal does not even reply to ping from another vlan while it is still fully functional from the same vlan. How exactly is this reset done - what is sent?
And what do you need to do to get it working again - replug the power?
I assume that the other terminals (old Coniugo) are still accessible from the other vlan?
Regards,
Bartłomiej
Hi!
As far as I an see, the software sends AT+CFUN=1,1 to reboot the modem.
I got network restored by bit of a coincidence:
I was looking around in the configuration, to see if i could find som network settings I had missed.
I found the Static Route page, and tried to add a static route. It did not work, so I removed it again. After pressing Save & Apply, the network connection worked again.
My guess is that when I press Save & Apply the network stack is somehow reset?
Hello,
With an AT command the ELS61-E module is rebooted. But it does not affect the OpenWrt System. So I'm a bit surprised that you have problems with accessing the terminal over LAN.
If, hypothetically, this causes any module related issues, you could have problem with accessing AT interface on the module but should still be able to ping the terminal over LAN or connect to OpenWrt console.
You are probably configuring the terminal via web GUI which is a part of OpenWrt system and I believe it is not modified by us anyhow. So honestly I'm not an expert on Linux systems but I agree with you that 'Save & Apply' most probably does some kind of reset to apply the changes.
Anyway the problem is how rebooting the module affects the LAN interface. I think it should not. For some time the wan access would obviously be lost if the module is rebooting. Can this problem disappear if the terminal is left for a while or not? Is the wan access restored after the reboot? Is AT interface available again from the local subnet?
Do you see any chance that it is related to your network infrastructure - for instance if the wan access is lost via this destination your router changes something in its routing table?
Best regards,
Bartłomiej