I am using UBUNTU operating system along with windows XP in my PC. I was using 'pppoeconf' in UBUNTU to connect to Internet through my ISP. But recently(2 months by now) Internet access through the same utility has stopped in Ubuntu. I am able to connect to my ISP, but not able to surf Internet. When I connect to net(using pon dsl-provider command), and give 'ifconfig' command, I see the following output ::
------------------------------------------------------------
ppp0 Link encapoint-to-Point Protocol
inet addr:221.128.197.90 P-t-P:202.63.173.66 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1492 Metric:1
RX packets:289 errors:0 dropped:0 overruns:0 frame:0
TX packets:397 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:3
RX bytes:222814 (217.5 KiB) TX bytes:38245 (37.3 KiB)
------------------------------------------------------------
I able to connect to my ISP website by giving its IP address (202.63.173.66). But when I give any other site's address (eg. www.yahoo.com), the browser status bar shows 'looking for ...', and no data is received. I also tried to ping DNS server(in /etc/resolve.conf file), and other sites's IP address (Google's IP address --> 64.233.167.99), but it fails.
I am able to connect to the internet successfully in Windows XP on the same PC.
Two of my friends having connection of the same ISP and using Linux OS is also facing the same problem.
Can you help us ?

The output of various commands on Ubuntu is appended as below ::

1. sudo ifconfig
---------------------------------------------------------------------
eth0 Link encap:Ethernet HWaddr 00:30:F1:4D:96:AC
inet addr:10.10.146.206 Bcast:10.10.255.255 Mask:255.255.0.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:2906572 errors:0 dropped:0 overruns:0 frame:0
TX packets:129740 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:584754941 (557.6 MiB) TX bytes:19303851 (18.4 MiB)
Interrupt:209 Base address:0xcc00

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:14 errors:0 dropped:0 overruns:0 frame:0
TX packets:14 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:1156 (1.1 KiB) TX bytes:1156 (1.1 KiB)

ppp0 Link encapoint-to-Point Protocol
inet addr:221.128.197.43 P-t-P:202.63.173.66 Mask:255.255.255.255
UP POINTOPOINT RUNNING NOARP MULTICAST MTU:1492 Metric:1
RX packets:304 errors:0 dropped:0 overruns:0 frame:0
TX packets:362 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:3
RX bytes:254099 (248.1 KiB) TX bytes:34781 (33.9 KiB)
-----------------------------------------------------------------------------

2. sudo ip a
-----------------------------------------------------------------------------
1: lo: <LOOPBACK,UP> mtu 16436 qdisc noqueue
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
2: eth0: <BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast qlen 1000
link/ether 00:30:f1:4d:96:ac brd ff:ff:ff:ff:ff:ff
inet 10.10.146.206/16 brd 10.10.255.255 scope global eth0
4: ppp0: <POINTOPOINT,MULTICAST,NOARP,UP> mtu 1492 qdisc pfifo_fast qlen 3
link/ppp
inet 221.128.197.43 peer 202.63.173.66/32 scope global ppp0
-------------------------------------------------------------------------------

3. sudo ip route
--------------------------------------------------------------------------------
202.63.173.66 dev ppp0 proto kernel scope link src 221.128.197.43
10.10.0.0/16 dev eth0 proto kernel scope link src 10.10.146.206
default dev ppp0 scope link
---------------------------------------------------------------------------------

4. sudo plog
----------------------------------------------------------------------------------
Jun 1 18:49:54 nk pppd[4955]: CHAP authentication succeeded: Welcome to XXXX.
Jun 1 18:49:54 nk pppd[4955]: CHAP authentication succeeded
Jun 1 18:49:54 nk pppd[4955]: peer from calling number 00:11:11:7DF:31 authorized
Jun 1 18:49:54 nk pppd[4955]: Cannot determine ethernet address for proxy ARP
Jun 1 18:49:54 nk pppd[4955]: local IP address 221.128.197.43
Jun 1 18:49:54 nk pppd[4955]: remote IP address 202.63.173.66
Jun 1 18:49:54 nk pppd[4955]: primary DNS address 202.63.164.17
Jun 1 18:49:54 nk pppd[4955]: secondary DNS address 202.63.164.18
--------------------------------------------------------------------------------------

5. sudo route -n
-------------------------------------------------------------------------------------
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
202.63.173.66 0.0.0.0 255.255.255.255 UH 0 0 0 ppp0
10.10.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0
0.0.0.0 0.0.0.0 0.0.0.0 U 0 0 0 ppp0
---------------------------------------------------------------------------------------

- Navneet Kataria