only one ping from router

[Tom H]

On Tue, Jun 18, 2013 at 12:10 PM, Josh Stratton
<strattonbrazil at gmail.com> wrote:


> The internet on my desktop suddenly stopped working while watching a video.
> I don't think anything has changed recently as far as configuration goes.
> It seems like the eth0 interface is getting an IP address from my router,
> but I can only ping myself. dns names don't resolve like if I ping
> yahoo.com. If I ping the router at 192.168.0.1, I seem to only get one
> response back before it hangs and times out. I've been trying to debug this
> myself, but I'm unfamiliar with what files are used for what now.
>
> Is there something I can do to fix networking? Other computers attached to
> the router don't seem to be having any issues.

Check what networking packages you have installed with

aptitude search ~i -F "%c %p" | grep -E 'dnsm|ifup|network|resolv'
or
dpkg-query -W -f '${Status}\t${Package}\n' dnsm* ifup* network* resolv*


> *** ifconfig
> eth0 Link encap:Ethernet HWaddr 00:24:1d:2a:8f:f7
> inet addr:192.168.0.6 Bcast:192.168.0.255 Mask:255.255.255.0
> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

OK.

It's better to use "ip a" (short of "ip address show") because
"ifconfig" is obsolete.

Since you seem to be using NM, "nm-tool" is even better


> *** cat /etc/resolv.conf
> File doesn't exist...
>
> *** ls -l /etc/resolv.conf
> Broken link

Recreate the symlink to "/run/resolvconf/resolv.conf".


> *** grep dns /etc/NetworkManager/NetworkManager.conf
> #dns=dsnmasq
>
> *** cat /var/run/nm-dns-dnsmasq.conf
> File doesn't exist...

Given the "#dns=dsnmasq" above, it cannot exist. And it doesn't matter.


> *** nslookup ubuntu.com
> ;; connection timed out; no servers could be reached
>
> *** dig ubuntuforums.org
> ;; connection timed out; no servers could be reached

They won't work without "/etc/resolv.conf".


> *** route -n
> Destination Gateway Genmask Flags Metric Ref Use Iface
> 169.254.0.0 0.0.0.0 255.255.0.0 U 1000 0 0 eth0
> 192.168.0.0 192.168.0.1 255.255.255.0 UG 0 0 0 eth0
> 192.168.0.0 0.0.0.0 255.255.255.0 U 1 0 0 eth0

You don't have a route leading out of your 192.168.0.0/24 network (and
two for your network...).

Your "UG" line if FUBAR.

It's better to use "ip r" (short of "ip route show") because "route"
is obsolete.

For the current boot, you can correct your routing table with:
ip r d 192.168.0.0/24 via 192.168.0.1 dev eth0
ip r a default via 192.168.0.1 dev eth0