Quote Originally Posted by Bataa
Please be noted, i made some mild changes to addresses for privacy as you suggested.
I think you'll find if you look over what I wrote that I did not suggest making any changes. I took exception with bad information that said to change or hide a MAC address in a post as that is completely bogus advice. Without knowing what is changed I'm handicapped in my ability to give you good advice. So if you feel that you must hide an IP address, do it by putting xxx's in the number, not by using other numbers. But you can't hide your IP address from any website that you visit. Unless you have some extreme security issue or your post makes you particularly attractive to hackers (as in "I work for BankAmerica and our IP address is 5.19.23.87"), I think it's needless paranoia. And in you case you do seem to have public routable IP addresses. If you have a web server or any other public server on any of these systems and a URL that can be translated by all of the Domain Name Servers to your IP address, then it's pretty pointless to muck it up when you are asking for help.

Quote Originally Posted by Bataa
.... We configure IP addresses
manually. Here I post the output after "ifconfig".

[root@localhost ~]# ifconfig
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:6020 errors:0 dropped:0 overruns:0 frame:0
TX packets:6020 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:9154718 (8.7 MiB) TX bytes:9154718 (8.7 MiB)

[root@localhost ~]# ifconfig
eth0 Link encap:Ethernet HWaddr 00:400:78:26:1D
inet addr:133.2.25.220 Bcast:133.2.25.255 Mask:255.255.255.0
inet6 addr: ae80::240:c0ff:fe75:411e/64 Scope:Link
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:2 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:168 (168.0 b)
Interrupt:5 Base address:0x6300

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:6025 errors:0 dropped:0 overruns:0 frame:0
TX packets:6025 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:9155165 (8.7 MiB) TX bytes:9155165 (8.7 MiB)

As you mention, there seems no problem at all. But I still can't connect internet.
I can't ping to any address. For example www.google.com (66.102.7.147)
After a while the response is :
From 133.2.25.220 icmp_seq=1 Destination Host Unreachable
From 133.2.25.220 icmp_seq=2 Destination Host Unreachable
From 133.2.25.220 icmp_seq=3 Destination Host Unreachable
From 133.2.25.220 icmp_seq=4 Destination Host Unreachable
From 133.2.25.220 icmp_seq=5 Destination Host Unreachable
From 133.2.25.220 icmp_seq=6 Destination Host Unreachable

And when I enter address in Mozilla browser. It says Looking up www.yahoo.com.
No response.
Without knowing what equipment you lab uses I'm hard pressed to know what you are doing wrong. The IP address, mask and broadcast all make sense, if they are really what you say, but I do see that they are all public addresses. That seems to imply that you are not behind a NAT router and the IP addresses of all of your systems can be reached from the Internet. You show a system with no more than 254 valid IP addresses. You say that you can'y ping the URL that you gave, but don't mention what happens if you try to ping the IP address that you also showed (if you can ping the IP address then you have a DNS issue, if you can't ping the IP address then you have some other problem (maybe in addition to a DNS issue). Beyond that without knowing what your network hardware is and what you are connecting to, there is not a lot I can tell you.

It is interesting and noteworthy that the actual NIC in use shows RX bytes:0 (0.0 b) TX bytes:168 (168.0 b). This would seem to indicate that the computer hasn't received any packets at al. But since you manually configure everything there might be no ARP packets floating around, and I have no knowledge of when you ran this ifconfig. If it happened after all of your tests then it's pretty telling, but if it was the first thing you did after booting then this isn't out of the question.

Just knowing the settings in one of the manually configured systems doesn't tell me much either. I would have to know how several systems are configured before I could have much chance of spotting any problems.