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Old 07-22-2011, 11:55 PM   #1
splinux
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Basic Network Problem .. cant ping, cant access internet..


I have two PCs. Default gateway 192.168.1.1

Virtual Box is installed on PC B

one PC A centos 192.168.1.2
one PC B Windows ( 192.168.1.3) and Centos(Inside the virtual box) 192.168.1.10.

after that i changed PC A ip as 192.168.1.10 then
i got the ip conflict message. it said cant assign that ip So i didnt change that ip


From the Cent OS (virtual box )
i could nt able ping to 192.168.1.1
or 192.168.1.2 or anyweb.


if i am able ping to 127.0.0.1 from Centos( Virtual box)


and i can use the internet from that windows OS..


how can i solve this issue ?

Last edited by splinux; 07-26-2011 at 07:45 AM.
 
Old 07-23-2011, 12:09 AM   #2
catkin
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Did you change PC A's IP to 192.168.1.10 or not?

Do you have any other devices on the network that may be using 192.168.1.10?

Is the virtual machine's network adapter type set to Bridged?
 
Old 07-23-2011, 12:17 AM   #3
splinux
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192.168.1.19 not using any other devices


in the virtual box that is in bridge mode..



/etc/resolv.conf
nameserver 192.168.1.1

Last edited by splinux; 07-23-2011 at 12:20 AM.
 
Old 07-23-2011, 12:39 AM   #4
catkin
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Do I correctly understand:
  1. PC A CentOS 192.168.1.2
  2. PC B Windows 192.168.1.3 VirtualBox host with VM configured with bridged network adapter running CentOS 192.168.1.10
  3. Gateway 192.168.1.1
  4. 192.168.1.10 definitely not being used by any network devices except the VM guest.
  5. CentOS (guest, not PC A) cannot ping 192.168.1.1 (gateway) 192.168.1.2 (PC A) or any (!) Internet address such as 75.126.162.205 (LQ)

Can
  1. PC A ping PC 192.168.1.3?
  2. PC A ping 192.168.1.10?
  3. PC B ping PC 192.168.1.2?
  4. PC B ping 192.168.1.10?
Ping tests may not be reliable from VirtualBox hosts, I vaguely recall they did not work on early versions, maybe only when pinging the host. Just tried pinging host under VirtualBox 3.2.12 and it did work.

As everything is being done by address, resolv.conf is not relevant.

Are you using the same netmask on all systems? Conventionally 255.255.255.0 for 192.168.x.x addresses.
 
Old 07-23-2011, 12:46 AM   #5
splinux
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if i type the

route add default gw 192.168.1.1

i am getting one error
SIOCAADDRT File Exists..

please refer the link


http://www.voodish.co.uk/articles/si...rk-ip-address/
 
Old 07-23-2011, 04:34 PM   #6
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I never use bridged, I use nat and it usually just works.
 
Old 07-24-2011, 11:04 AM   #7
catkin
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It would help if you answered questions asked and if you said which system you ran the route add on.
 
Old 07-24-2011, 12:08 PM   #8
splinux
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Cent OS ( Inside the virtual box )
if i type here i am getting that message..
 
Old 07-25-2011, 02:19 AM   #9
catkin
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The default gateway is only relevant to get to IP addresses outside the LAN, that is outside 192.168.1.x. As I understand it, CentOS in the VM cannot ping LAN addresses including the default gateway so it is very unlikely that accessing IP addresses outside the LAN will work.

Do I correctly understand:
  1. PC A CentOS 192.168.1.2
  2. PC B Windows 192.168.1.3 VirtualBox host with VM configured with bridged network adapter running CentOS 192.168.1.10
  3. Gateway 192.168.1.1
  4. 192.168.1.10 definitely not being used by any network devices except the VM guest.
  5. CentOS (guest, not PC A) cannot ping 192.168.1.1 (gateway) 192.168.1.2 (PC A) or any (!) Internet address such as 75.126.162.205 (LQ)
Can
  1. PC A ping PC 192.168.1.3?
  2. PC A ping 192.168.1.10?
  3. PC B ping PC 192.168.1.2?
  4. PC B ping 192.168.1.10?
Following jefro's post, have you tried configuring the VM's network adapter to NAT, configuring its OS to use DHCP and trying to access addresses on the Internet? If that works we would know the components are working and could concentrate on configuring bridged with static IP.
 
Old 07-26-2011, 07:48 AM   #10
splinux
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PC A can ping to 192.168.1.3 (Windows ) yeah can ping
PC A CANT ping to 192.168.1.10 Cent OS( Virtual Box guest OS )
PC B can ping to 192.168.1.2 yea can ping
PC B windows CANT ping to Cent OS ( virtual box guest OS )
 
Old 07-26-2011, 09:17 AM   #11
catkin
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Quote:
Originally Posted by splinux View Post
PC A can ping to 192.168.1.3 (Windows ) yeah can ping
PC A CANT ping to 192.168.1.10 Cent OS( Virtual Box guest OS )
PC B can ping to 192.168.1.2 yea can ping
PC B windows CANT ping to Cent OS ( virtual box guest OS )
Thanks for confirming.

So CentOS in the VM seems not to be on the LAN.

Getting information on the host ... When CentOS in the VM is running, what is the output when the user running the VM runs these commands on the host (where <machine name> is as listed by VBoxManage list vms)
Code:
VBoxManage list bridgedifs
VBoxManage list vms
VBoxManage showvminfo "<machine name>" | grep '^NIC'
Getting information on the guest ... What is the output from these command run as root on the VM
Code:
ifconfig
cat /etc/sysconfig/network-scripts/ifcfg-eth0
iptables --list
route -n
 
Old 07-27-2011, 09:38 AM   #12
splinux
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Thx for every one help.. i have written some NAT rules in the iptables.
but i used this command iptables -F
then all the rules flushed except NAT rules.
after i deleted those rules now it working...
 
  


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