Hello,
We are facing some problems with quectel EC-21 modem. Basically sometimes the module restarts continuously for big random time (minutes or hours). The only message we get from our embedded OS is “Modem Hangup”. Is there any posibility to debug the modem and be able to get more information about what is happening? We need any type of clue to get closer to the issue. Some extra-logs from the modem could help.This is very critical.
Greentings,
Are you using the PPP？ Is it Linux?
Could you provide the complete PPP log. Modem Hangup is not an explicit error. Normally, customers are required to provide modem log.
Yes, we are using ppp daemon.
Yes, it is a custom embedded linux.
Provide modem log? What modem log are you referring to?
The following is what we get constanstly:
Tue Dec 31 01:38:13 2024 daemon.notice netifd: Interface 'wan' is now down
Tue Dec 31 01:38:13 2024 daemon.notice netifd: Interface 'wan' is setting up now
Tue Dec 31 01:38:15 2024 daemon.notice pppd[14323]: pppd 2.4.7 started by root, uid 0
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: abort on (BUSY)
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: abort on (NO CARRIER)
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: abort on (ERROR)
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: report (CONNECT)
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: timeout set to 10 seconds
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: send (AT&F^M)
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: expect (OK)
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: AT&F^M^M
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: OK
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: -- got it
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: send (ATE1^M)
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: expect (OK)
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: ^M
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: ATE1^M^M
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: OK
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: -- got it
Tue Dec 31 01:38:16 2024 local2.info chat[14328]: send (AT+CGDCONT=1,"IP","TM"^M)
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: timeout set to 30 seconds
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: expect (OK)
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: ^M
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: AT+CGDCONT=1,"IP","TM"^M^M
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: OK
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: -- got it
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: send (ATD*99***1#^M)
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: expect (CONNECT)
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: ^M
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: ATD*99***1#^M^M
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: CONNECT
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: -- got it
Tue Dec 31 01:38:17 2024 local2.info chat[14328]: send ( ^M)
Tue Dec 31 01:38:17 2024 daemon.info pppd[14323]: Serial connection established.
Tue Dec 31 01:38:17 2024 kern.info kernel: wwan-wan: renamed from ppp0
Tue Dec 31 01:38:17 2024 daemon.info pppd[14323]: Using interface wwan-wan
Tue Dec 31 01:38:17 2024 daemon.notice pppd[14323]: Connect: wwan-wan <--> /dev/ttyUSB3
Tue Dec 31 01:38:18 2024 daemon.info pppd[14323]: CHAP authentication succeeded
Tue Dec 31 01:38:18 2024 daemon.notice pppd[14323]: CHAP authentication succeeded
Tue Dec 31 01:38:18 2024 daemon.notice pppd[14323]: Modem hangup
Tue Dec 31 01:38:18 2024 daemon.notice pppd[14323]: Connection terminated.
Tue Dec 31 01:38:19 2024 daemon.err rtty: (rtty.c:545) Inactive too long time
Tue Dec 31 01:38:19 2024 daemon.info pppd[14323]: Exit.
Tue Dec 31 01:38:19 2024 daemon.notice netifd: Interface 'wan' is now down
Tue Dec 31 01:38:19 2024 daemon.notice netifd: Interface 'wan' is setting up now
Tue Dec 31 01:38:21 2024 daemon.notice pppd[14380]: pppd 2.4.7 started by root, uid 0
Tue Dec 31 01:38:22 2024 local2.info chat[14382]: abort on (BUSY)
Tue Dec 31 01:38:22 2024 local2.info chat[14382]: abort on (NO CARRIER)
Tue Dec 31 01:38:22 2024 local2.info chat[14382]: abort on (ERROR)
Tue Dec 31 01:38:22 2024 local2.info chat[14382]: report (CONNECT)
Tue Dec 31 01:38:22 2024 local2.info chat[14382]: timeout set to 10 seconds
Tue Dec 31 01:38:22 2024 local2.info chat[14382]: send (AT&F^M)
Tue Dec 31 01:38:22 2024 local2.info chat[14382]: expect (OK)
Tue Dec 31 01:38:22 2024 local2.info chat[14382]: AT&F^M^M
Tue Dec 31 01:38:22 2024 local2.info chat[14382]: OK
Tue Dec 31 01:38:22 2024 local2.info chat[14382]: -- got it
Tue Dec 31 01:38:22 2024 local2.info chat[14382]: send (ATE1^M)
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: expect (OK)
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: ^M
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: ATE1^M^M
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: OK
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: -- got it
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: send (AT+CGDCONT=1,"IP","TM"^M)
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: timeout set to 30 seconds
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: expect (OK)
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: ^M
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: AT+CGDCONT=1,"IP","TM"^M^M
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: OK
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: -- got it
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: send (ATD*99***1#^M)
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: expect (CONNECT)
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: ^M
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: ATD*99***1#^M^M
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: CONNECT
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: -- got it
Tue Dec 31 01:38:23 2024 local2.info chat[14382]: send ( ^M)
Tue Dec 31 01:38:23 2024 daemon.info pppd[14380]: Serial connection established.
Tue Dec 31 01:38:23 2024 kern.info kernel: wwan-wan: renamed from ppp0
Tue Dec 31 01:38:23 2024 daemon.info pppd[14380]: Using interface wwan-wan
Tue Dec 31 01:38:23 2024 daemon.notice pppd[14380]: Connect: wwan-wan <--> /dev/ttyUSB3
Tue Dec 31 01:38:24 2024 daemon.info pppd[14380]: CHAP authentication succeeded
Tue Dec 31 01:38:24 2024 daemon.notice pppd[14380]: CHAP authentication succeeded
Tue Dec 31 01:38:24 2024 daemon.notice pppd[14380]: Modem hangup
Tue Dec 31 01:38:24 2024 daemon.notice pppd[14380]: Connection terminated.
Tue Dec 31 01:38:25 2024 daemon.info pppd[14380]: Exit.
Greetings
Have you checked that
Could you show the dmesg log? can you try the usbnet?
/dev/ttyUSB3 is not being used by another process.
yeah, it seems usb disconnects… The modem is attached to 4 ports Hub USB.
So… Hub is restarting? Modem? maybe hw supply problem?
There is the dmesg log
usb 1-1.1: new high-speed USB device number 5 using ci_hdrc
usb 1-1.1: New USB device found, idVendor=2c7c, idProduct=0121
usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-1.1: Product: EC21-EUX
usb 1-1.1: Manufacturer: Quectel
usb 1-1.1: SerialNumber: 0123456789ABCDEF
option 1-1.1:1.0: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB0
option 1-1.1:1.1: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB1
option 1-1.1:1.2: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB2
option 1-1.1:1.3: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB3
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
usb 1-1.1: USB disconnect, device number 5
option1 ttyUSB0: GSM modem (1-port) converter now disconnected from ttyUSB0
option 1-1.1:1.0: device disconnected
option1 ttyUSB1: GSM modem (1-port) converter now disconnected from ttyUSB1
option 1-1.1:1.1: device disconnected
option1 ttyUSB2: GSM modem (1-port) converter now disconnected from ttyUSB2
option 1-1.1:1.2: device disconnected
option1 ttyUSB3: GSM modem (1-port) converter now disconnected from ttyUSB3
option 1-1.1:1.3: device disconnected
usb 1-1.1: new high-speed USB device number 6 using ci_hdrc
usb 1-1.1: New USB device found, idVendor=2c7c, idProduct=0121
usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-1.1: Product: EC21-EUX
usb 1-1.1: Manufacturer: Quectel
usb 1-1.1: SerialNumber: 0123456789ABCDEF
option 1-1.1:1.0: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB0
option 1-1.1:1.1: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB1
option 1-1.1:1.2: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB2
option 1-1.1:1.3: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB3
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
usb 1-1.1: USB disconnect, device number 6
option1 ttyUSB0: GSM modem (1-port) converter now disconnected from ttyUSB0
option 1-1.1:1.0: device disconnected
option1 ttyUSB1: GSM modem (1-port) converter now disconnected from ttyUSB1
option 1-1.1:1.1: device disconnected
option1 ttyUSB2: GSM modem (1-port) converter now disconnected from ttyUSB2
option 1-1.1:1.2: device disconnected
option1 ttyUSB3: GSM modem (1-port) converter now disconnected from ttyUSB3
option 1-1.1:1.3: device disconnected
usb 1-1.1: new high-speed USB device number 7 using ci_hdrc
usb 1-1.1: New USB device found, idVendor=2c7c, idProduct=0121
usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-1.1: Product: EC21-EUX
usb 1-1.1: Manufacturer: Quectel
usb 1-1.1: SerialNumber: 0123456789ABCDEF
option 1-1.1:1.0: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB0
option 1-1.1:1.1: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB1
option 1-1.1:1.2: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB2
option 1-1.1:1.3: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB3
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
usb 1-1.1: USB disconnect, device number 7
option1 ttyUSB0: GSM modem (1-port) converter now disconnected from ttyUSB0
option 1-1.1:1.0: device disconnected
option1 ttyUSB1: GSM modem (1-port) converter now disconnected from ttyUSB1
option 1-1.1:1.1: device disconnected
option1 ttyUSB2: GSM modem (1-port) converter now disconnected from ttyUSB2
option 1-1.1:1.2: device disconnected
option1 ttyUSB3: GSM modem (1-port) converter now disconnected from ttyUSB3
option 1-1.1:1.3: device disconnected
usb 1-1.1: new high-speed USB device number 8 using ci_hdrc
usb 1-1.1: New USB device found, idVendor=2c7c, idProduct=0121
usb 1-1.1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-1.1: Product: EC21-EUX
usb 1-1.1: Manufacturer: Quectel
usb 1-1.1: SerialNumber: 0123456789ABCDEF
option 1-1.1:1.0: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB0
option 1-1.1:1.1: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB1
option 1-1.1:1.2: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB2
option 1-1.1:1.3: GSM modem (1-port) converter detected
usb 1-1.1: GSM modem (1-port) converter now attached to ttyUSB3
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
wwan-wan: renamed from ppp0
For usbnet… do you mean the AT command “AT+QCFG=“usbnet”,<0-3>”?
Could you show
ls /sys/bus/usb/drivers
I mean that maybe you can try the quectel-CM with qmi_wwan.
Could you show
lsof | grep ttyUSB
Just from the dmesg log we can see that the usb device disconnect some time, but we don’t know whether it is the root cause the the pppd exit.
Maybe the powersupply is not stable.
I only can add 1 media at a time, so i put everything together:
Normally pppd is active. As pppd is restarting, it is changing its PID. Between that restart it seems another programs are using ttyUSB3.
Greetings,
So please find which process that open the ttyUSB3.
Just check
lsof | grep ttyUSB
From the picture it seems that your script that open the ttyUSB3…
