EC25-E Mini PCIE Port Changing

Technical Subjects Software General Function
1

On OpenWRT devices, we use QUECTEL EC25-E GSM Module, sometimes internet is disconnecting, when it disconnect we send AT+CFUN=1,1 to GSM Modem.
Before send command devices are;

crw-------    1 root     root      188,   0 Jun 27 15:35 /dev/ttyUSB0
crw-------    1 root     root      188,   1 Jun 27 15:35 /dev/ttyUSB1
crw-------    1 root     root      188,   2 Jun 27 15:35 /dev/ttyUSB2
crw-------    1 root     root      188,   3 Jun 27 15:35 /dev/ttyUSB3

After I send command

crw-------    1 root     root      188,   0 Jun 27 15:39 /dev/ttyUSB0
crw-------    1 root     root      188,   2 Jun 27 17:46 /dev/ttyUSB2
crw-------    1 root     root      188,   3 Jun 27 15:39 /dev/ttyUSB3
crw-------    1 root     root      188,   4 Jun 27 15:39 /dev/ttyUSB4

devices are changing, it results internet cannot be connected.

We use 100 Module per month, but we could not solve it yet. If fd is using this port it happens. But we even do not use that fd but it still changes its port.
Is there a way to prevent?

2

Try using USB rebind instead of +CFUN.

3

Is that a safe way? I mean will it have any effect? Do you know about it? Or do you use it in that way?

4

Standard and safe. This method is used among others in this OpenWrt based firmware.
Works fine with my EC25 and EP06.

Please do me a favor and check fw version (ATI) and temperature (AT+QTEMP) on any of your EC25 modems and post this in EC25 +QTEMP reporting

5

Hi, thanks for your information, yes I can give it a try. But I can say mini PCIE become quite hot. It is like 50 C degree