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I am using Windows 7. Here is a correct ipconfig which helps me connect to Internet:

IPv4 Address
Subnet Mask
Default Gateway

It happens so often that in the morning when I first turn on my computer, the Default Gateway was assigned as so I could not connect to Internet and had to set a static Default Gateway myself.

There are two IPs that my default gateway is randomly assigned: (correct) (incorrect)

I don't know where the value of comes from. I can not ping I checked on my router setup page ( but could not find any proof.

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closed as off-topic by Jenny D, Iain, MichelZ, HopelessN00b, Rex Apr 18 '14 at 14:30

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You should consult with your system administrator. This is probably a DHCP issue / multiple DHCP issue – MichelZ Apr 18 '14 at 8:24
Unfortunately, I am taking the role as a system administrator now and still don't know where is the second DHCP server. – trogerx Apr 18 '14 at 8:41
If you get .252 again, have a look at ipconfig /all, it will list you the IP Address of the DHCP Server where the settings came from – MichelZ Apr 18 '14 at 8:46
Using ipconfig /all I found out that the second DHCP server is on a Win 2008 server machine, turn this DHCP server off and I solved the issue, thanks. – trogerx Apr 18 '14 at 9:21

2 Answers 2

up vote 1 down vote accepted

Also because we don't know anything about your network and if we assume that it's big LAN it's possible that there is seccond DHCP server in network (even with the same IP as right DHCP so you won't figure it out) and give IP address to you faster than right DHCP server. Network administrator can easily find second DHCP server in LAN using dhcpdump (linux software).

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I am trying to find the second DHCP server now, thanks. – trogerx Apr 18 '14 at 8:41
You wrote that you get IP from If your default gateway is also DHCP Server and it's configured to set cliets gateway to and still your clients get from default gateway you should just change (for a test period) your DHCP Server IP from to some other IP and try to ping If it replies check it's MAC with command arp -a and you have seccond DHCP mac. Change your DHCP server IP back to Find mac of seccond DHCP on switches and turn this port down. – vonom Apr 18 '14 at 8:44

Did you check your router DHCP settings ? DHCP is responsible for giving you your IP address and also your gateway.

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I can see on my router config page: DHCP Gateway: – trogerx Apr 18 '14 at 8:12

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