pppd connection with GSM/GPRS modem, re-dialing after a few times

Question

I'm currently connecting my GSM/GPRS modem HUAWEI e1550 to my ISP's network. I'm able to get it connected, but after disconnecting and connecting a few times I'm not able to do it anymore, and my modem starts not to answer, and I don't no why!

I connect through pppd call tmn-3g <- my ISP conf ppp file This is my /etc/ppp/chat file:

ABORT BUSY
ABORT 'NO CARRIER'
ABORT ERROR
REPORT CONNECT
TIMEOUT 10
"" "ATZ"
OK "AT&F"
OK 'AT+CGDCONT=1,"IP","internet"'
SAY "Calling...\n"
TIMEOUT 120
OK "ATD*99***1#"
CONNECT \c

And here is my /etc/ppp/peers/tmn-3g

/dev/ttyUSB0  
460800
lock
crtscts
modem
noauth
defaultroute
user tmn 
password tmn 
connect "/usr/sbin/chat -V -f /etc/ppp/chat-tmn-3g"
noipdefault
usepeerdns
nobsdcomp
novj

Can you help me with this?

Is it possible to restart my usb ports so that I can restart all the process?I though this could be a solution..

Or is there any other way to do it?

tks in advance..

Answer 1

This is more a comment than an answer (don't have comment privilege on stackoverflow...)

Seems this thread is about a similar issue.
I had a somewhat similar one as well, maybe this can help.