OpenWrt Forum Archive

Topic: 3G - Connecting but then disconnecting

The content of this topic has been archived on 8 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

Hi
I am trying to get a Vodafone K3770 3G USB dongle working on my Alix board (using trunk R29611).
I have followed closely the 3G howto guide and as the title suggests, I am connecting and then it disconnects.

I know that usb_modeswitch has worked as I can see in the output from dmesg

root@OpenWrt:# dmesg
.....
.....

[   17.509317] usb 1-1: new high speed USB device number 2 using ehci_hcd
[   18.161685] usb 1-1: USB disconnect, device number 2
[   25.705798] usb 1-1: new high speed USB device number 3 using ehci_hcd
[   26.197157] option 1-1:1.0: GSM modem (1-port) converter detected
[   26.215803] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB0
[   26.237249] option 1-1:1.3: GSM modem (1-port) converter detected
[   26.255784] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB1

and also from the usb listing:

Bus 001 Device 003: ID 12d1:14c9 Huawei Technologies Co., Ltd.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

The chat script is as per the howto, as is the wan section of the network (apart from the debug option which I added to see what was happening):

root@OpenWrt:# cat /etc/config/network

config 'interface' 'loopback'
        option 'ifname' 'lo'
        option 'proto' 'static'
        option 'ipaddr' '127.0.0.1'
        option 'netmask' '255.0.0.0'

config 'interface' 'lan'
        option 'ifname' 'eth0'
        option 'proto' 'dhcp'

config 'interface' 'wan'
        option ifname 'ppp0'
        option proto 3g
        option service umts
        option device /dev/ttyUSB0
        option apn ppbundle.internet
        option username web
        option password web
        option pppd_options 'debug'

The apn and username/password pair work ok on my Ubuntu laptop

When reviewing the log it seems the device is connecting but unable the get an IP address and then gives up.

Feb 14 16:25:22 OpenWrt daemon.debug pppd[1559]: Script USE_APN=ppbundle.internet /usr/sbin/chat -t5 -v -E -f /etc/chatscripts/3g.chat finished (pid 1724), status = 0x0
Feb 14 16:25:22 OpenWrt daemon.info pppd[1559]: Serial connection established.
Feb 14 16:25:22 OpenWrt daemon.debug pppd[1559]: using channel 9
Feb 14 16:25:22 OpenWrt daemon.info pppd[1559]: Using interface 3g-wan
Feb 14 16:25:22 OpenWrt daemon.notice pppd[1559]: Connect: 3g-wan <--> /dev/ttyUSB0
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: sent [LCP ConfReq id=0x5 <asyncmap 0x0> <magic 0xd60e94a2>]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: rcvd [LCP ConfReq id=0x1 <accomp> <pcomp> <asyncmap 0x0> <mru 1500> <magic 0x54b> <auth chap MD5>]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: sent [LCP ConfRej id=0x1 <accomp> <pcomp>]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: rcvd [LCP ConfAck id=0x5 <asyncmap 0x0> <magic 0xd60e94a2>]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: rcvd [LCP ConfReq id=0x2 <asyncmap 0x0> <mru 1500> <magic 0x54b> <auth chap MD5>]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: sent [LCP ConfAck id=0x2 <asyncmap 0x0> <mru 1500> <magic 0x54b> <auth chap MD5>]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: sent [LCP EchoReq id=0x0 magic=0xd60e94a2]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: rcvd [CHAP Challenge id=0x1 <07a5d91db515cb85fe786d732ed7b9c1>, name = "HUAWEI_CHAP_SRVR"]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: sent [CHAP Response id=0x1 <99af1390e0258ceb3c5069c1a881c9d5>, name = "web"]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: rcvd [LCP EchoRep id=0x0 magic=0x54b]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: rcvd [CHAP Success id=0x1 "Welcome!!"]
Feb 14 16:25:23 OpenWrt daemon.info pppd[1559]: CHAP authentication succeeded: Welcome!!
Feb 14 16:25:23 OpenWrt daemon.notice pppd[1559]: CHAP authentication succeeded
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: sent [IPCP ConfReq id=0x35 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: rcvd [IPCP ConfReq id=0x1]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: sent [IPCP ConfNak id=0x1 <addr 0.0.0.0>]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: rcvd [IPCP ConfNak id=0x35 <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: sent [IPCP ConfReq id=0x36 <addr 0.0.0.0> <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: rcvd [IPCP ConfReq id=0x2]
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: sent [IPCP ConfAck id=0x2]
Feb 14 16:25:23 OpenWrt daemon.info pppd[1559]: Hangup (SIGHUP)
Feb 14 16:25:23 OpenWrt daemon.notice pppd[1559]: Modem hangup
Feb 14 16:25:23 OpenWrt daemon.notice pppd[1559]: Connection terminated.

The howto intimates that a default address should be allocated from somewhere but does not say where. Can anyone shed any light or point me in the right direction?

Thanks

Had the same problem. Try adding: option 'pppd_options' 'noipdefault' under interface wan setting in /etc/config/network.

Hi
Thanks for the reply. Tried the noipdefault option but got the same results.

Hi
Yes I read that post and the symptoms I have are exactly the same but the solution is not working for me.
I am going to start from a fresh install to ensure I have not made a mistake.

garyc wrote:
Feb 14 16:25:23 OpenWrt daemon.debug pppd[1559]: rcvd [IPCP ConfNak id=0x35 <ms-dns1 0.0.0.0> <ms-dns2 0.0.0.0>]

Workaround,

uci add network.wan.peerdns=0
uci add network.wan.dns="8.8.8.8 8.8.4.4"
uci commit network

The discussion might have continued from here.