在ARM-LINUX平台实现4G模块PPP拨号上网（串口/USB）

Mad99cat

串口拨号
解压ppp程序包，交叉编译

1. #tar -xzvf ppp-2.4.5.tar.gz
   
2. #cd ./ppp-2.4.5
   
3. #./config
   
4. #make CC=arm-linux-gcc

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内核配置
Device Drivers —>Network device support—> <*> PPP (point-to-point protocol) support

ppp安装
将交叉编译好的pppd、chat应用复制到开发平台下的/usr/sbin/下。将ppp、chatscripts两个文件夹复制到开发平台下的/etc/目录下。

PPP配置
修改配置文件 /etc/ppp/peers/provider

1. #example configuration for a dialup connection authenticated with PAP or CHAP
   
2. #
   
3. # This is the default configuration used by pon(1) and poff(1).
   
4. # See the manual page pppd(8) for information on all the options.
   
5. # MUST CHANGE: replace myusername@realm with the PPP login name given to
   
6. # your by your provider.
   
7. # There should be a matching entry with the password in /etc/ppp/pap-secrets
   
8. # and/or /etc/ppp/chap-secrets.
   
9. #user "myusername@realm"
   
10. # Serial device to which the modem is connected.
    
11. # ttyname 串口端口，若非以”/“开头，则会自动补充”/dev/“
    
12. /dev/ttyS6
    
13. #/dev/ttyUSB2
    
14. #NO硬件流控
    
15. nocrtscts
    
16. # 前台运行
    
17. nodetach
    
18. # speed 串口波特率
    
19. # Speed of the serial line.
    
20. #115200
    
21. 9600
    
22. #hide-password
    
23. remotename cmnet
    
24. ipparam cmnet
    
25. debug
    
26. user "cmnet"
    
27. 0.0.0.0:0.0.0.0
    
28. local
    
29. lock
    
30. dump
    
31. # Assumes that your IP address is allocated dynamically by the ISP.
    
32. # 由ISP提供IP
    
33. noipdefault
    
34. # Try to get the name server addresses from the ISP.
    
35. usepeerdns
    
36. # Use this connection as the default route.
    
37. #defaultroute
    
38. # Makes pppd "dial again" when the connection is lost.
    
39. persist
    
40. # Do not ask the remote to authenticate.
    
41. noauth
    
42. 
    

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修改拨号脚本 /etc/chatscripts/pap

1. #you can use this script unmodified to connect to sites which allow
   
2. # authentication via PAP, CHAP and similar protocols.
   
3. # This script can be shared among different pppd peer configurations.
   
4. # To use it, add something like this to your /etc/ppp/peers/ file:
   
5. #
   
6. # connect "/usr/sbin/chat -v -f /etc/chatscripts/pap -T PHONE-NUMBER"
   
7. # user YOUR-USERNAME-IN-PAP-SECRETS
   
8. # noauth
   
9. # Uncomment the following line to see the connect speed.
   
10. # It will be logged to stderr or to the file specified with the -r chat option.
    
11. #REPORT                CONNECT
    
12. TIMEOUT                15
    
13. ABORT                "BUSY"
    
14. ABORT                "DELAYED"
    
15. ABORT                "ERROR"
    
16. ABORT                "NO DIALTONE"
    
17. ABORT                "NO CARRIER"
    
18. TIMEOUT                40
    
19. 
    
20. ''                AT
    
21. OK                 AT+CSQ
    
22. #  s模块APN设置报错，默认接入CMNET，注释掉此命令
    
23. #OK                 AT+CGDCONT=1,"IP","CMNET"
    
24. OK                ATDT*99#
    
25. CONNECT
    
26. 
    

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修改pap权限
chmod +x /etc/chatscripts/pap

串口通信测试
打开两个终端
cat /dev/ttyS*
另一个终端发送AT命令
echo “AT” > /dev/ttyS*

可以cat到 AT OK，通信成功。若通信失败请用模块默认波特率。

串口拨号
pppd call provider &

1. # pppd call provider &
   
2. pppd options in effect:
   
3. debug                # (from /etc/ppp/peers/provider)
   
4. nodetach                # (from /etc/ppp/peers/provider)
   
5. persist                # (from /etc/ppp/peers/provider)
   
6. dump                # (from /etc/ppp/peers/provider)
   
7. noauth                # (from /etc/ppp/peers/provider)
   
8. user cmnet                # (from /etc/ppp/peers/provider)
   
9. remotename cmnet                # (from /etc/ppp/peers/provider)
   
10. /dev/ttyUSB2                # (from /etc/ppp/peers/provider)
    
11. 9600                # (from /etc/ppp/peers/provider)
    
12. lock                # (from /etc/ppp/peers/provider)
    
13. connect /usr/sbin/chat -s -v -f /etc/chatscripts/pap                # (from /etc/ppp/peers/provider)
    
14. nocrtscts                # (from /etc/ppp/peers/provider)
    
15. local                # (from /etc/ppp/peers/provider)
    
16. asyncmap 0                # (from /etc/ppp/options)
    
17. lcp-echo-failure 4                # (from /etc/ppp/options)
    
18. lcp-echo-interval 30                # (from /etc/ppp/options)
    
19. hide-password                # (from /etc/ppp/options)
    
20. ipparam cmnet                # (from /etc/ppp/peers/provider)
    
21. noipdefault                # (from /etc/ppp/peers/provider)
    
22. usepeerdns                # (from /etc/ppp/peers/provider)
    
23. :                # (from /etc/ppp/peers/provider)
    
24. noipx                # (from /etc/ppp/options)
    
25. timeout set to 15 seconds
    
26. abort on (BUSY)
    
27. abort on (DELAYED)
    
28. abort on (ERROR)
    
29. abort on (NO DIALTONE)
    
30. abort on (NO CARRIER)
    
31. timeout set to 40 seconds
    
32. send (AT^M)
    
33. expect (OK)
    
34. AT^M^M
    
35. OK
    
36. -- got it
    
37. 
    
38. send (AT+CSQ^M)
    
39. expect (OK)
    
40. ^M
    
41. AT+CSQ^M^M
    
42. +CSQ: 25,99^M
    
43. OK
    
44. -- got it
    
45. 
    
46. send (ATDT*99#^M)
    
47. expect (CONNECT)
    
48. ^M
    
49. ATDT*99#^M^M
    
50. CONNECT
    
51. -- got it
    
52. 
    
53. Script /usr/sbin/chat -s -v -f /etc/chatscripts/pap finished (pid 1448), status = 0x0
    
54. Serial connection established.
    
55. using channel 1
    
56. Using interface ppp0
    
57. Connect: ppp0 <--> /dev/ttyUSB2
    
58. sent [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xdb90a4ab> <pcomp> <accomp>]
    
59. rcvd [LCP ConfReq id=0x0 <asyncmap 0x0> <auth pap> <magic 0xc1e41549> <pcomp> <accomp>]
    
60. No auth is possible
    
61. sent [LCP ConfRej id=0x0 <auth pap>]
    
62. rcvd [LCP ConfAck id=0x1 <asyncmap 0x0> <magic 0xdb90a4ab> <pcomp> <accomp>]
    
63. rcvd [LCP ConfReq id=0x1 <asyncmap 0x0> <magic 0xc1e41549> <pcomp> <accomp>]
    
64. sent [LCP ConfAck id=0x1 <asyncmap 0x0> <magic 0xc1e41549> <pcomp> <accomp>]
    
65. sent [LCP EchoReq id=0x0 magic=0xdb90a4ab]
    
66. sent [CCP ConfReq id=0x1 <deflate 15> <deflate(old#) 15> <bsd v1 15>]
    
67. sent [IPCP ConfReq id=0x1 <compress VJ 0f 01> <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]
    
68. rcvd [LCP DiscReq id=0x2 magic=0xc1e41549]
    
69. rcvd [LCP EchoRep id=0x0 magic=0xc1e41549 db 90 a4 ab]
    
70. rcvd [LCP ProtRej id=0x3 80 fd 01 01 00 0f 1a 04 78 00 18 04 78 00 15 03 2f]
    
71. Protocol-Reject for 'Compression Control Protocol' (0x80fd) received
    
72. rcvd [IPCP ConfReq id=0x0 <addr 10.0.0.1>]
    
73. sent [IPCP ConfAck id=0x0 <addr 10.0.0.1>]
    
74. rcvd [IPCP ConfRej id=0x1 <compress VJ 0f 01>]
    
75. sent [IPCP ConfReq id=0x2 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]
    
76. rcvd [IPCP ConfNak id=0x2 <addr 100.109.117.176> <ms-dns1 211.136.17.107> <ms-dns2 211.136.20.203>]
    
77. sent [IPCP ConfReq id=0x3 <addr 100.109.117.176> <ms-dns1 211.136.17.107> <ms-dns2 211.136.20.203>]
    
78. rcvd [IPCP ConfAck id=0x3 <addr 100.109.117.176> <ms-dns1 211.136.17.107> <ms-dns2 211.136.20.203>]
    
79. local  IP address 100.109.117.176
    
80. remote IP address 10.0.0.1
    
81. primary   DNS address 211.136.17.107
    
82. secondary DNS address 211.136.20.203
    
83. Script /etc/ppp/ip-up started (pid 1453)
    
84. 
    
85. Script /etc/ppp/ip-up finished (pid 1453), status = 0x0
    
86. 
    

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#ifconfig

1. # ifconfig
   
2. docker0   Link encap:Ethernet  HWaddr 02:42:28:F3:6C:11  
   
3.           inet addr:172.17.0.1  Bcast:172.17.255.255  Mask:255.255.0.0
   
4.           UP BROADCAST MULTICAST  MTU:1500  Metric:1
   
5.           RX packets:0 errors:0 dropped:0 overruns:0 frame:0
   
6.           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
   
7.           collisions:0 txqueuelen:0
   
8.           RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
   
9. 
   
10. eth0      Link encap:Ethernet  HWaddr FE:C4:84:AF:B7:CE  
    
11.           inet addr:192.168.0.2  Bcast:192.168.0.255  Mask:255.255.255.0
    
12.           inet6 addr: fe80::fcc4:84ff:feaf:b7ce/64 Scope:Link
    
13.           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
    
14.           RX packets:628 errors:0 dropped:0 overruns:0 frame:0
    
15.           TX packets:466 errors:4 dropped:0 overruns:0 carrier:0
    
16.           collisions:0 txqueuelen:1000
    
17.           RX bytes:57929 (56.5 KiB)  TX bytes:78074 (76.2 KiB)
    
18.           Interrupt:117
    
19. 
    
20. lo        Link encap:Local Loopback  
    
21.           inet addr:127.0.0.1  Mask:255.0.0.0
    
22.           inet6 addr: ::1/128 Scope:Host
    
23.           UP LOOPBACK RUNNING  MTU:65536  Metric:1
    
24.           RX packets:0 errors:0 dropped:0 overruns:0 frame:0
    
25.           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
    
26.           collisions:0 txqueuelen:0
    
27.           RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
    
28. 
    
29. ppp0      Link encap:Point-to-Point Protocol  
    
30.           inet addr:100.109.117.176  P-t-P:10.0.0.1  Mask:255.255.255.255
    
31.           UP POINTOPOINT RUNNING NOARP MULTICAST  MTU:1500  Metric:1
    
32.           RX packets:4 errors:0 dropped:0 overruns:0 frame:0
    
33.           TX packets:5 errors:0 dropped:0 overruns:0 carrier:0
    
34.           collisions:0 txqueuelen:3
    
35.           RX bytes:64 (64.0 B)  TX bytes:97 (97.0 B)
    
36. 
    
37. 
    

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可以看到ppp0网卡

添加路由
#route add default dev ppp0
联网测试
#ping 8.8.8.8

1. PING 8.8.8.8 (8.8.8.8): 56 data bytes
   
2. 64 bytes from 8.8.8.8: seq=0 ttl=50 time=44.137 ms
   
3. 64 bytes from 8.8.8.8: seq=1 ttl=50 time=41.198 ms
   
4. 64 bytes from 8.8.8.8: seq=2 ttl=50 time=47.619 ms
   
5. 64 bytes from 8.8.8.8: seq=3 ttl=50 time=40.627 ms
   
6. 64 bytes from 8.8.8.8: seq=4 ttl=50 time=46.058 ms
   

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ping域名如果失败，请添加DNS
从/etc/ppp/resolv.conf可以查看到当前运营商的DNS“nameserver 211.136.17.107”，将DNS"nameserver 211.136.17.107 # ppp0"添加到/etc/resolv.conf.重新拨号，done。

USB拨号

查看4G模块
ls /dev/ttyUSB*

1. /dev/ttyUSB0  /dev/ttyUSB1  /dev/ttyUSB2  /dev/ttyUSB3
   

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可以看到模块驱动加载成功，枚举出4个ttyUSB设备，查看模块手册：
ttyUSB0 专用数据业务端口
ttyUSB1 GPS
ttyUSB2 AT指令端口
ttyUSB3 诊断口
修改配置文件 /etc/ppp/peers/provider

1. /dev/ttyS6
   
2. #/dev/ttyUSB2
   

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修改为：

1. #/dev/ttyS6
   
2. /dev/ttyUSB2
   

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拨号测试
拨号和网络配置部分同串口拨号一样。

如果ls /dev/ttyUSB*看不到设备，可以执行lsusb

1. # lsusb
   
2. Bus 002 Device 003: ID 2949:7401
   
3. Bus 002 Device 001: ID 1d6b:0002
   
4. Bus 004 Device 001: ID 1d6b:0001
   

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查阅模块手册，VID和PID为2949:7401，可以看到已经识别到模块。
手动添加U转串驱动：

1. sudo echo 2949 7401 > /sys/bus/usb-serial/drivers/option1/new_id
   

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此时重新ls /dev/ttyUSB*即可看到设备。如果设备重启，需要重新手动添加U转串驱动。

拨号
后续步骤跟串口拨号相同。

fengyunyu

高大上，厉害

jim166783

请教下出错重新拨号是怎么处理的

sbusr

4G模块有的提供USB网卡的驱动，这和PPP拨号相比，有什么差异？

qsun

用modemmanager比裸ppp方便和稳定

Mad99cat

qsun 发表于 2020-11-18 05:27
用modemmanager比裸ppp方便和稳定

  等有时间研究一下

youkebing

jim166783 发表于 2020-11-17 19:44
请教下出错重新拨号是怎么处理的

我们以前是定时监测那个网卡，发现没有，重新拨号，多次不成功后，重启系统，或者重启网卡