I have a raspberry Pi with three interfaces eth0 (Ethernet), wlan0 (WiFi), and wwan0 (via a GSM modem)

  1. How can I test if an Internet connection is available via a certain interface? e.g. is my GSM(wwan0) modem connected to the Internet?

  2. If I attempt to run ping www.google.com - How do I know what interface is being used?

closed as off-topic by Morgan Courbet, Jivings Oct 1 '14 at 16:12

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question does not appear to be specific to the Raspberry Pi within the scope defined in the help center." – Morgan Courbet, Jivings
If this question can be reworded to fit the rules in the help center, please edit the question.

  • 1
    Hi there. It looks as if your question would be better suited on a different Stack Exchange site as it is more related to general Linux operation, rather than Raspberry Pi specifics. If you like I can migrate this question to a relevant place? – Jivings Oct 1 '14 at 16:13
  • 2
    Good question though - Unix & Linux may be ideal for it. – Wilf Oct 1 '14 at 16:22
  • @Morgan - unix.stackexchange.com/questions/158901/… – OneGuyInDc Oct 3 '14 at 13:07