no internet access in cent os 5.5

dushyantgohil · 12-19-2011, 11:28 PM

hi,
i am using cent os 5.5, i am not able to access internet through this machine.machine is connected with router,when system gets dhcp from router internet is working but when i am entering ip manually internet is not working.

btmiller · 12-19-2011, 11:39 PM

If you're router is assigning IP addresses through DHCP, why do you need to set the IP manually? Can you post the commands you use or describe the steps you take to set the IP address? Are you sure that you're setting an IP that is valid for your network and is not already in use by another computer or other device? When you set the IP, can you ping the IP address of your router? Do you remember to set your default gatrway to the IP address of the router?

Some more information would really help diagnose this.

fukawi1 · 12-19-2011, 11:41 PM

It sounds like you aren't configuring the static ip propperly.

Is the subnet right?
Route?
nameserver in /etc/resolve.conf?

dushyantgohil · 12-23-2011, 12:01 AM

Quote:

Originally Posted by btmiller

If you're router is assigning IP addresses through DHCP, why do you need to set the IP manually? Can you post the commands you use or describe the steps you take to set the IP address? Are you sure that you're setting an IP that is valid for your network and is not already in use by another computer or other device? When you set the IP, can you ping the IP address of your router? Do you remember to set your default gatrway to the IP address of the router?

Some more information would really help diagnose this.

its server and router is generating different ip every time so it creates problem for client and router doesn't having functionality of binding mac address that's why i need to assign ip statically.i can ping the router's ip as well my gateway and dns too.

dushyantgohil · 12-23-2011, 12:06 AM

Quote:

Originally Posted by fukawi1

It sounds like you aren't configuring the static ip propperly.

Is the subnet right?
Route?
nameserver in /etc/resolve.conf?

every thing is correct, i can ping my self ip,gateway,dns and router ip perfectly. i can access local network from this server, client are accessing server perfectly but not able to access internet.

dushyantgohil · 12-23-2011, 12:17 AM

Quote:

Originally Posted by fukawi1

It sounds like you aren't configuring the static ip propperly.

Is the subnet right?
Route?
nameserver in /etc/resolve.conf?

i have make entry in resolve.conf but after restarting the network service its been like the file before, so the entries which i have done in resolve.conf are not there.

fukawi1 · 12-23-2011, 12:39 AM

To isolate if it is a DNS related problem, can you ping an external address, by IP, rather than name?

As btmiller suggested, how are you configuring the static IP?

Can you post the output of

Code:

cat /etc/sysconfig/network-scripts/ifcfg-ethX

dushyantgohil · 12-23-2011, 03:55 AM

i have also tried multiple ip on single network card tric for this in that i was able to access internet as well local network but after restarting the server the secondary ip is being stored automatically as a master ip of server.

deep27ak · 12-23-2011, 06:12 AM

Quote:

Originally Posted by dushyantgohil

i have make entry in resolve.conf but after restarting the network service its been like the file before, so the entries which i have done in resolve.conf are not there.

I am surprised to see resolve.conf all the time because as far as I know it should be

resolv.conf

as asked by fukawi1

post the output of

Code:

#cat /etc/sysconfig/network-scripts/ifcfg-ethx
#cat /etc/sysconfig/network
#cat /etc/resolv.conf

post these output as well and please use code tags

and ping status of any website

Code:

#ping google.com -t

Code:

#ping your gateway
#ping dns server