ethernet doesn't work

Hello, I just got my BeagleBone Black but when I logged in (with the ethernet plugged) and tried to install some libraries to begin tinkering with
it I found out I couldn’t download anything, then I found out I couldn’t even ping google.com or other common sites. I have already flashed it
with the latest angstrom distribution available on the site but it is still not working :(.

I can only ping myself (127.0.0.1) and the other 2 ips I can find when I try ifconfig -a, but I can´t receive a response from any server after I
ping (100% loss of packages). I would like to know if there is a possible soltuion I could try on my board, or if I got a defective one…

Thanks in advance.

Have you tested your network connection with another device?

try following:

  1. “ifconfig -a” to check the IP address configured on the device
  2. check if you can connect/ping to any other host in same network.
  3. check default gateway on the BBB, using: “route -n”
  4. check the DNS settings - also try to do “ping 4.2.2.1”
  5. try “tracepath -n 4.2.2.1”

also provide the outputs of above commands.

ifconfig -a :

eth0 Link encap:Ethernet HWaddr C8:A0:30:AD:17:88
inet addr:172.17.89.242 Bcast:172.17.89.255 Mask:255.255.255.0
inet6 addr: fe80::caa0:30ff:fead:1788/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1007 errors:0 dropped:0 overruns:0 frame:0
TX packets:58 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:362237 (353.7 KiB) TX bytes:10889 (10.6 KiB)
Interrupt:56

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:4 errors:0 dropped:0 overruns:0 frame:0
TX packets:4 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:761 (761.0 B) TX bytes:761 (761.0 B)

usb0 Link encap:Ethernet HWaddr 8A:D6:A4:D1:73:32
inet addr:192.168.7.2 Bcast:192.168.7.3 Mask:255.255.255.252
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1796 errors:0 dropped:0 overruns:0 frame:0
TX packets:563 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:182906 (178.6 KiB) TX bytes:334280 (326.4 KiB)

route -n:

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 172.17.89.254 0.0.0.0 UG 0 0 0 eth0
172.17.89.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
172.17.89.254 0.0.0.0 255.255.255.255 UH 0 0 0 eth0
192.168.7.0 0.0.0.0 255.255.255.252 U 0 0 0 usb0
192.168.55.55 172.17.89.254 255.255.255.255 UGH 0 0 0 eth0

ping 4.2.2.1:

PING 4.2.2.1 (4.2.2.1) 56(84) bytes of data.
^C
— 4.2.2.1 ping statistics —
9 packets transmitted, 0 received, 100% packet loss, time 8008ms

tracepath -n 4.2.2.1:

1: 172.17.89.242 0.711ms pmtu 1500
1: no reply
2: no reply
3: no reply
4: no reply

ifconfig -a :

eth0 Link encap:Ethernet HWaddr C8:A0:30:AD:17:88
inet addr:172.17.89.242 Bcast:172.17.89.255 Mask:255.255.255.0
inet6 addr: fe80::caa0:30ff:fead:1788/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1007 errors:0 dropped:0 overruns:0 frame:0
TX packets:58 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:362237 (353.7 KiB) TX bytes:10889 (10.6 KiB)
Interrupt:56

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:4 errors:0 dropped:0 overruns:0 frame:0
TX packets:4 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:761 (761.0 B) TX bytes:761 (761.0 B)

usb0 Link encap:Ethernet HWaddr 8A:D6:A4:D1:73:32
inet addr:192.168.7.2 Bcast:192.168.7.3 Mask:255.255.255.252
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:1796 errors:0 dropped:0 overruns:0 frame:0
TX packets:563 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:182906 (178.6 KiB) TX bytes:334280 (326.4 KiB)

route -n:

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
0.0.0.0 172.17.89.254 0.0.0.0 UG 0 0 0 eth0
172.17.89.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0
172.17.89.254 0.0.0.0 255.255.255.255 UH 0 0 0 eth0
192.168.7.0 0.0.0.0 255.255.255.252 U 0 0 0 usb0
192.168.55.55 172.17.89.254 255.255.255.255 UGH 0 0 0 eth0

ping 4.2.2.1:

PING 4.2.2.1 (4.2.2.1) 56(84) bytes of data.
^C
— 4.2.2.1 ping statistics —
9 packets transmitted, 0 received, 100% packet loss, time 8008ms

tracepath -n 4.2.2.1:

1: 172.17.89.242 0.711ms pmtu 1500
1: no reply
2: no reply
3: no reply
4: no reply

Your configuration seems correct but it seems you cannot connect to
your default gateway also.

Please try to ping you default gateway also: "ping -c 10 172.17.89.254"
(ping to 172.17.89.254 should work unless ICMP blocked)

If you couldn't ping your default gateway also then check your physical
connectivity like ethernet cable and RJ45 connectors etc.

Also have a look at dmesg output to check if there are any errors related
to network.

root@beaglebone:~# ping -c 10 172.17.89.254

PING 172.17.89.254 (172.17.89.254) 56(84) bytes of data.
64 bytes from 172.17.89.254: icmp_req=1 ttl=64 time=0.267 ms
64 bytes from 172.17.89.254: icmp_req=2 ttl=64 time=0.231 ms
64 bytes from 172.17.89.254: icmp_req=3 ttl=64 time=0.276 ms
^C
— 172.17.89.254 ping statistics —
3 packets transmitted, 3 received, 0% packet loss, time 1999ms
rtt min/avg/max/mdev = 0.231/0.258/0.276/0.019 ms

Your board is able to communicate with default gateway
so network connectivity is correct.

Default gateway is not routing the packets further to next hop.

You will not be able to connect to Internet even if you replace BBB
with any other host/laptop also. And this doesn't seems problem
of BBB.

So check the settings at 172.17.89.254 if its a NATed router
or behind/is a firewall ?

You might have to set HTTP proxy if you are behind HTTP
web proxy server. Try following if this is the case:

  $ sudo /bin/bash
  # export http_proxy='http://YOUR-WEB-PROXY-IP:PORT'
  # opkg update

But this is weird, I use the same exact ethernet connection on my Laptop everyday and I can connect to the internet perfectly.