iptables rules unable to work when using mobile broadband

[resettler 0]

I access the internet using AirVPN. With the help of iptables rules all out-going traffic from my machine to the internet is dropped instantly when my VPN connection is abruptly terminated.

The iptables rules work on a wired connection but they do not when I am using mobile broadband.

I tried to solve the problem by sudo-ing and editing the file /etc/udev/rules.d/70-persistent-net.rules to include the following line:

# Mobile Broadband USB dongle
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*", ATTR{address}=="MAC address of dongle", ATTR{dev_id}=="0x0", ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"

 

Additional details

To get mobile broadband to work on Debian 7.9, I carried out the following steps:

1. Add the following line to /lib/udev/rules.d/40-usb_modeswitch.rules

# Mobile Broadband USB dongle
ATTRS{idVendor}=="19d2", ATTRS{idProduct}=="0257", RUN+="usb_modeswitch '%b/%k'"

2. Create a file called 19d2:0257 in /etc/usb_modeswitch.d/ with the following contents:

# Mobile Broadband USB dongle
#
DefaultVendor= 0x19d2
DefaultProduct= 0x0257
TargetVendor= 0x19d2
TargetProduct= 0x0257
MessageContent="55534243123456782400000080000685000000240000000000000000000000"
CheckSuccess=20 

3. In order for Network Manager to recognize the device automatically, I add the following line to /etc/rc.local

modprobe usbserial vendor=0x19d2 product=0x0257