Cellular Connectivity Troubleshooting
Diagnostics - Troubleshooting Cell Interface (ppp0), Check Signal Strength
Verify with the cellular provider that you have an activated account.
For GSM/HSPA modems, ensure that you have the mini-SIM card properly installed in the RediGate.
To troubleshoot the cellular communication on a RediGate, log in using the 'user' account. The following steps will be described here, followed by other instructions to diagnose certain problems.
1. Check Cell Modem Diagnostics
================ Main Menu ==============
ElecSys(V:5.7.2017-02-23-1000) Thu Mar 2 18:09:02 2017
RediGate400C_CPLX : 1 @ 10.63.192.192 REDIGATE-400 <Use System Serv Option-123>
---------------------------------------------
1) System Services
2) Directory Services
3) Diagnostics Services
99 Log Off
Enter '1' for System Services.
Make selection: 1
================ System Services ==============
ElecSys(V:5.7.2017-02-23-1000) Thu Mar 2 18:09:07 2017
RediGate400C_CPLX : 1 @ 10.63.192.192 REDIGATE-400 <Use System Serv Option-123>
---------------------------------------------
1) Boot/Reconfigure 2) Set Clock
3) Channel Status 4) Channel Enable/Disable
5) Channel Scan 6) Single Poll
7) RTU Enable/Disable 8) RTU Scan
9) RPN Calculator 10) New Master Key
11) Read Handshake Pins 12) Write Handshake Pins
13) Run Custom Utility 14) MQttClient to Next Broker
15) Cell Modem Diags
Enter '15' for Cell Modem Diags.
Make selection: 15
================ Cell Modem Diags ==============
ElecSys(V:5.7.2017-02-23-1000) Thu Mar 2 18:09:19 2017
RediGate400C_CPLX : 1 @ 10.63.192.192 REDIGATE-400 <Use System Serv Option-123>
---------------------------------------------
Virtual Port Numer
73=Diag AT Cmds
75=Auto-ATs or NMEA/GPS if HE-910
77=NMEA/GPS if DE-910
79=CellLEDsEnter '
73' for the virtual port number. After this, the RediGate will automatically request several AT commands from the modem.This information provides some modem and activation information (see the Diagnostics Manual for more detail on the output of these commands).
or 0 to Exit? 73
Sending AT+GMM
Received[15]-> HE910 OK
The GMM command give the modem type (HE910 = GSM, DE910-DUAL = EVDO).
Sending AT+CNUM
Received[37]-> +CNUM: "","19132109122",129 OK
The CNUM command gives the phone number associated with the account.
Sending AT#CCID
Received[37]-> #CCID: 89014104277578463113 OK
The CCID command gives the SIM card number (GSM only).
Sending AT+CGDCONT?
Received[42]-> +CGDCONT: 1,"IP","m2m.com.attz","",0,0 OK
The CGDCONT command gives the APN name (GSM only).
Verify that the above APN (such as "m2m.com.attz") is correct for the GSM modem account activation.
Sending AT#MEIDESN?
Received[9]-> #MEIDESN: A1000032B304F6,000000000000,00000000
The MEIDESN command gives the MEID (EVDO only) as a 14-digit hexadecimal number.
The MEID is the modem identification number required to activate the modem on Verizon. (see below for a different form of the MEID)
Sending AT#CIMI
Received[32]-> #CIMI: 310410757846311 OK
The CIMI command gives the IMSI (International Mobile Subscriber Identity) number. For GSM, this requires the SIM card to be present.
Sending AT#CGSN
Received[32]-> #CGSN: 357164042289457 OK
For GSM: The CGSN command gives the modem's hardware serial number.
For EVDO: The CGSN command gives the modem's MEID as an 18-digit decimal number.
Sending AT+CREG?
Received[20]-> +CREG: 0,1 OK
The CREG command gives the registration status of the modem (number after the comma).
Registration status is: 0=not registered, 1=registered/home, 2=searching, 3=denied, 5=registered/roaming
Sending AT$GPSACP
Received[30]-> $GPSACP: 214127.000,3853.5898N,09447.4488W,0.9,315.4,3,0.0,0.0,0.0,310715,07 OK
The GPSACP command gives GPS information, if GPS antenna is attached.
Sending AT+CSQ
Received[40]-> +CSQ: 28,3 OK
The first number after +CSQ is the signal strength. 99=no signal, 0=31 indicates increasing strength. If the number is 99 or a small number, there is a problem with getting adequate signal strength at the antenna location.
Enter 'n' to not repeat.
Repeat? (y/n) n
Then enter ' to repeat the last command continuously (+CSQ). This will allow you to monitor the signal strength over a period of time, if needed.
Enter AT Command (Enter to Exit, 'A/' repeats last, 'A//' repeat every 2 secs) a//
Press Q<enter> to quit repeating
Sending[8]-> AT+CSQ
Received[20]-> +CSQ: 28,2 OK
Press Q<enter> to quit repeating
Sending[8]-> AT+CSQ
Received[20]-> +CSQ: 29,2 OK
Enter 'q' to stop the AT+CSQ commands. And 'Enter' again to exit the menu.
q Enter AT Command (Enter to Exit, 'A/' repeats last, 'A//' repeat every 2 secs)Enter AT Command (Enter to Exit, 'A/' repeats last, 'A//' repeat every 2 secs)
2. View ModemLog.txt
================ Main Menu ==============
ElecSys(V:5.7.2017-02-23-1000) Thu Mar 2 18:35:34 2017
RediGate400C_CPLX : 1 @ 10.63.192.192 REDIGATE-400 <Use System Serv Option-123>
---------------------------------------------
1) System Services
2) Directory Services
3) Diagnostics Services
99 Log OffEnter '2' to stop the AT+CSQ commands. And 'Enter' again to exit the menu.
Make selection: 2
================ Directory Services ==============
ElecSys(V:5.7.2017-02-23-1000) Thu Mar 2 18:35:36 2017
RediGate400C_CPLX : 1 @ 10.63.192.192 REDIGATE-400 <Use System Serv Option-123>
---------------------------------------------
1) Executables 2) Current Configs
3) Download Directory 4) Put File to Remote
5) Get File From Remote 6) Rename File
7) Delete File in Remote 8) Delete IsaGraf Files
9) View Zombie.log 10) IsaGraf App Info
11) Restore Previous UFF 12) View UFF Processing Details
13) View Load-Store File 14) View kernel or message logs
15) MQtt XML Information 16) View customer settings
17) ZMODEM File to Remote 18) ZMODEM File from Remote
19) View Problem.txt 20) View ModemLog.txt
Enter '20' to view the ModemLog.txt file.
Press the space bar to page through the file, which shows one or more sequences of AT commands used for connection.
Make selection: 20
------------- CellModem script, ver. 1.4 ----------------------* * *
->AT+CSQ...OK<-+CSQ: 31,2\r\n\r\nOK->ATD*99***1#...CONNECT<-CONNECTRunning pppd /dev/ttyEMUX0 230400 file /dev/null local nocrtscts lock asyncmap 0 nodetach defaultroute noauth usepeerdnsUsing interface ppp0Connect: ppp0 <--> /dev/ttyEMUX0not replacing existing default route via 10.63.255.128local IP address 166.130.92.39remote IP address 166.130.92.39primary DNS address 166.216.138.41secondary DNS address 166.216.138.42Press ENTER...
If the last set ends with IP address, this indicates the address of the modem on the network.
3. Refer to Telit modem manual
For GSM (AT&T) RediGates, look at the Telit HE910 manual for information on AT commands: HE910 Manual
For CDMA (Verizon) modems, look at the Telit DE910 manual for information on AT commands: DE910 Manual
Problem - Cell Interface (ppp0) Will Not Connect
Logging into the RediGate as root and running the Linux command "ifconfig" does not show PPP0 interface. The same information can be obtained from the 'user' menu, Diagnostics Menu option 2.
You should see something similar to the text below if the cellular modem is configured correctly and connected:
A properly configured RediGate 400C with 2 enabled ethernet ports and a cellular connection is shown below, with addresses for eth0, eth1, and ppp0 (cellular).
<<<< ElecSys Linux RediGate 400 >>>> Name: (RediGate400C) Unit: (1) Eth0-IP: 0.0.0.0 armv5tel RediGate400C.(none) 3.12.9-00044-g5a52a4b
RediGate400C login: rootPassword:Hello root. Your path is /bin:/sbin:/usr/bin:/usr/sbin:/usr/bin/X11:/usr/local/bin:/usr/director/bin
[root@RediGate400C ~ ]$ ifconfigeth0 Link encap:Ethernet HWaddr E2:E0:32:B5:ED:32inet addr:10.63.192.151 Bcast:10.63.255.255 Mask:255.255.0.0inet6 addr: fe80::e0e0:32ff:feb5:ed32/64 Scope:LinkUP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1RX packets:15148 errors:0 dropped:29 overruns:0 frame:0TX packets:57 errors:0 dropped:0 overruns:0 carrier:0collisions:0 txqueuelen:0RX bytes:2015623 (1.9 MiB) TX bytes:5017 (4.8 KiB)
eth1 Link encap:Ethernet HWaddr E2:E0:32:B5:ED:32inet addr:192.168.1.10 Bcast:192.168.1.255 Mask:255.255.255.0inet6 addr: fe80::e0e0:32ff:feb5:ed32/64 Scope:LinkUP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1RX packets:0 errors:0 dropped:0 overruns:0 frame:0TX packets:11 errors:0 dropped:0 overruns:0 carrier:0collisions:0 txqueuelen:0RX bytes:0 (0.0 B) TX bytes:878 (878.0 B)
eth_base Link encap:Ethernet HWaddr E2:E0:32:B5:ED:32inet6 addr: fe80::e0e0:32ff:feb5:ed32/64 Scope:LinkUP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1RX packets:15148 errors:0 dropped:0 overruns:0 frame:0TX packets:84 errors:0 dropped:0 overruns:0 carrier:0collisions:0 txqueuelen:1000RX bytes:2348879 (2.2 MiB) TX bytes:7467 (7.2 KiB)Interrupt:64 Base address:0x8000
lo Link encap:Local Loopbackinet addr:127.0.0.1 Mask:255.0.0.0inet6 addr: ::1/128 Scope:HostUP LOOPBACK RUNNING MTU:65536 Metric:1RX packets:0 errors:0 dropped:0 overruns:0 frame:0TX packets:0 errors:0 dropped:0 overruns:0 carrier:0collisions:0 txqueuelen:0RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
ppp0 Link encap:Point-to-Point Protocolinet addr:166.130.92.39 P-t-P:166.130.92.39 Mask:255.255.255.255UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1500 Metric:1RX packets:25 errors:0 dropped:0 overruns:0 frame:0TX packets:7 errors:0 dropped:0 overruns:0 carrier:0collisions:0 txqueuelen:3RX bytes:880 (880.0 B) TX bytes:135 (135.0 B)
Below is an example of the diagnostic errors returned from a RG-400C (GSM) with an improperly installed SIM:
RediGate400C login: user
Password:
================ Main Menu ==============
ElecSys(V:5.7.2016-11-28-1300) Tue Nov 30 06:00:12 1999
RediGate400C : 1 @ 0.0.0.0 REDIGATE-400 <Use System Serv Option-123>
---------------------------------------------
1) System Services
2) Directory Services
3) Diagnostics Services99 Log Off
Make selection: 1
================ System Services ==============
ElecSys(V:5.7.2016-11-28-1300) Tue Nov 30 06:00:20 1999
RediGate400C : 1 @ 0.0.0.0 REDIGATE-400 <Use System Serv Option-123>
---------------------------------------------
1) Boot/Reconfigure 2) Set Clock
3) Channel Status 4) Channel Enable/Disable
5) Channel Scan 6) Single Poll
7) RTU Enable/Disable 8) RTU Scan
9) RPN Calculator 10) New Master Key
11) Read Handshake Pins 12) Write Handshake Pins
13) Run Custom Utility 14) MQttClient to Next Broker
15) Cell Modem DiagsMake selection: 15
================ Cell Modem Diags ==============
ElecSys(V:5.7.2016-11-28-1300) Tue Nov 30 06:00:23 1999
RediGate400C : 1 @ 0.0.0.0 REDIGATE-400 <Use System Serv Option-123>
---------------------------------------------
Virtual Port Numer
73=Diag AT Cmds
75=Auto-ATs or NMEA/GPS if HE-910
77=NMEA/GPS if DE-910
79=CellLEDs
or 0 to Exit? 73
Sending AT+GMM
Received[15]-> HE910 OK
Sending AT+CNUM
Received[9]-> ERRORIf the SIM card is missing or installed improperly, the #CCID command returns ERROR (notice the signal strength, +CSQ, returns a good number so the cellular signal is okay):
Sending AT#CCID
Received[9]-> ERROR
Sending AT+CGDCONT?
Received[9]-> ERROR
Sending AT#MEIDESN?
Received[9]-> ERROR
Sending AT#CIMI
Received[9]-> ERROR
Sending AT#CGSN
Received[32]-> #CGSN: 357164042289457 OK
Sending AT+CREG?
Received[20]-> +CREG: 0,0 OK
Sending AT$GPSACP
Received[19]-> $GPSACP: OK
Sending AT+CSQ
Received[20]-> +CSQ: 30,2 OK
Repeat? (y/n)
Solution
- Install the SIM card correctly (image below is CORRECT orientation). Metal contacts should be facing DOWN, with the notched edge of the card toward the RIGHT.
- Correctly configure the APN for a GSM (HE-910) modem.
- Check the signal strength. Attach or reorient cellular antenna to improve the signal.
For GSM/HSPA modems, see the following pages for a more complete description of the SIM card installation.