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beardo28
August 11th, 2009, 11:52 PM
Hi, just recently installed ubuntu, internet was working fine, it then asked me to install some updates, did that and restarted the computer and since then the internet does not work. The network manager shows that its connected to the network, but thats about it. its a wired network. can anyone help please?

jonobr
August 11th, 2009, 11:56 PM
Hello And welcome to the forums,

You should list what you have hardware wise, including your machine, nic if possible, then your connection to the internet, what type of service you have and if there is anything about your home network that may be of interest.

If your just connecting to a broadband router, dialup, wireless etc.
Are you using DHCP or static IP addressing?



Then if you open a terminal window and supply the output of ifconfig, that may help to figure whats going on

beardo28
August 12th, 2009, 12:15 AM
ok so a bit more info on my setup

laptop with nvidia network card, broadband internet connection through a wired router, using dhcp,

ifconfig:

eth0 Link encap:Ethernet HWaddr 00:1b:24:98:93:21
inet addr:192.168.1.3 Bcast:192.168.1.255 Mask:255.255.255.0
inet6 addr: fe80::21b:24ff:fe98:9321/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:7 errors:0 dropped:0 overruns:0 frame:0
TX packets:31 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:2540 (2.5 KB) TX bytes:5034 (5.0 KB)
Interrupt:20 Base address:0x2000

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:16436 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)

jonobr
August 12th, 2009, 06:09 AM
hello

could you try the following

ping 192.168.1.3

ping 192.168.1.1

nslookup pingplotter.com

nslookup google.com
post the results of the above

then open a browser and type in

http://216.92.151.75

What do you get???


Are you using pppoe from your ISP?

beardo28
August 12th, 2009, 01:09 PM
tried them
PING 192.168.1.3 (192.168.1.3) 56(84) bytes of data.
64 bytes from 192.168.1.3: icmp_seq=1 ttl=64 time=0.077 ms
64 bytes from 192.168.1.3: icmp_seq=2 ttl=64 time=0.023 ms
64 bytes from 192.168.1.3: icmp_seq=3 ttl=64 time=0.020 ms
64 bytes from 192.168.1.3: icmp_seq=4 ttl=64 time=0.037 ms
64 bytes from 192.168.1.3: icmp_seq=5 ttl=64 time=0.021 ms
64 bytes from 192.168.1.3: icmp_seq=6 ttl=64 time=0.021 ms
64 bytes from 192.168.1.3: icmp_seq=7 ttl=64 time=0.018 ms
64 bytes from 192.168.1.3: icmp_seq=8 ttl=64 time=0.023 ms
64 bytes from 192.168.1.3: icmp_seq=9 ttl=64 time=0.051 ms
64 bytes from 192.168.1.3: icmp_seq=10 ttl=64 time=0.034 ms

--- 192.168.1.3 ping statistics ---
10 packets transmitted, 10 received, 0% packet loss, time 8995ms
rtt min/avg/max/mdev = 0.018/0.032/0.077/0.018 ms

PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data.
64 bytes from 192.168.1.1: icmp_seq=1 ttl=255 time=0.806 ms
64 bytes from 192.168.1.1: icmp_seq=2 ttl=255 time=0.696 ms
64 bytes from 192.168.1.1: icmp_seq=3 ttl=255 time=0.708 ms
64 bytes from 192.168.1.1: icmp_seq=4 ttl=255 time=0.701 ms
64 bytes from 192.168.1.1: icmp_seq=5 ttl=255 time=0.693 ms
64 bytes from 192.168.1.1: icmp_seq=6 ttl=255 time=0.563 ms
64 bytes from 192.168.1.1: icmp_seq=7 ttl=255 time=0.686 ms
64 bytes from 192.168.1.1: icmp_seq=8 ttl=255 time=0.698 ms
64 bytes from 192.168.1.1: icmp_seq=9 ttl=255 time=0.681 ms
64 bytes from 192.168.1.1: icmp_seq=10 ttl=255 time=0.691 ms

--- 192.168.1.1 ping statistics ---
10 packets transmitted, 10 received, 0% packet loss, time 9001ms
rtt min/avg/max/mdev = 0.563/0.692/0.806/0.058 ms


nslookup pingplotter.com:
Server: 192.168.1.1
Address: 192.168.1.1#53

** server can't find pingplotter.com: SERVFAIL


nslookup google.com:
;; connection timed out; no servers could be reached

I'm pretty sure that i'm using pppoe from my isp.

jonobr
August 12th, 2009, 04:33 PM
Looks like your not getting anything back from your DNS

what about the ping to 216.92.151.75
and also putting that ip address into your browser

beardo28
August 12th, 2009, 07:09 PM
PING 216.92.151.75 (216.92.151.75) 56(84) bytes of data.
From 192.168.1.1 icmp_seq=1 Destination Net Unreachable
From 192.168.1.1 icmp_seq=2 Destination Net Unreachable
From 192.168.1.1 icmp_seq=3 Destination Net Unreachable
From 192.168.1.1 icmp_seq=4 Destination Net Unreachable
From 192.168.1.1 icmp_seq=5 Destination Net Unreachable
From 192.168.1.1 icmp_seq=6 Destination Net Unreachable
From 192.168.1.1 icmp_seq=7 Destination Net Unreachable
From 192.168.1.1 icmp_seq=8 Destination Net Unreachable
From 192.168.1.1 icmp_seq=9 Destination Net Unreachable
From 192.168.1.1 icmp_seq=10 Destination Net Unreachable

--- 216.92.151.75 ping statistics ---
10 packets transmitted, 0 received, +10 errors, 100% packet loss, time 9000ms

When entering it into a browser it came up failed to connect

jonobr
August 12th, 2009, 07:19 PM
Hello

Just want to check your router is setup correctly?

Can you verify that the router is connected to the internet,

Is the machine you are doing posts here with using the same router?

beardo28
August 12th, 2009, 07:21 PM
yes it is conected to the internet, i'm using the smae router to post on here.

jonobr
August 12th, 2009, 08:07 PM
Interesting,

Im not a fan of fiddling with MTU size
but see what running this does


sudo ifconfig eth0 mtu 1450

If that doesnt work we can always change MTU back to 1500

beardo28
August 12th, 2009, 08:49 PM
still not working

jonobr
August 12th, 2009, 08:56 PM
WHats you assigned IP address of your broadband router?

Is there a web screen that shows you what that is
Does it have admin screens to show you the assigned DNS IP and public IP address?

jonobr
August 12th, 2009, 09:01 PM
I would also recommend that you reset MTU to 1500
you check the MTU size in use on your working machine.
and that you post the results of

cat /etc/resolv.conf
and
cat /etc/nsswitch.conf

beardo28
August 12th, 2009, 09:51 PM
ok, router does have amin screen:

router ip, not 100% on this one is likely to be this one 212.248.157.74 or 192.168.2.1, and with regards to public ip i'm guessing it will be one of those as well.
DNS: 195.8.160.64

beardo28
August 12th, 2009, 09:58 PM
results of those files:

# Generated by NetworkManager
nameserver 192.168.1.1



# /etc/nsswitch.conf
#
# Example configuration of GNU Name Service Switch functionality.
# If you have the `glibc-doc-reference' and `info' packages installed, try:
# `info libc "Name Service Switch"' for information about this file.

passwd: compat
group: compat
shadow: compat

hosts: files mdns4_minimal [NOTFOUND=return] dns mdns4
networks: files

protocols: db files
services: db files
ethers: db files
rpc: db files

netgroup: nis

jonobr
August 12th, 2009, 10:29 PM
ok so can you ping 212.248.157.74

also what does the 192.168.2.1 ip address refer to?

That sounds odd

beardo28
August 13th, 2009, 12:03 PM
ok so tried pinging that and failed. the 212 ip address, having a had another look at the setup of the network is for the modem, and the 192 ip address is for the router, don't know if this makes any difference. i did manage to get internet working last night by going straight to the modem, and entering the settings manually, but this only works if i go straight to the modem and isn't a long term solution.

jonobr
August 13th, 2009, 04:44 PM
Hello


What do you mean by "straight to the modem?

The 192.168.2 address is probably the problem as the 192.168.1.3 cannot route to 192.168.2.1 IP address.

Understanding your network setup is important.