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DHCP issue in our network, could it be hidden 2nd DHCP server?

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http://serverfault.com – Something weird happened today. We have a TP-LINK wifi router in our office distributing a pool of IPs 192.168.80-200. There are some windows and some linux boxes. One of the linux boxes (CentOS) today booted up with IP 192.168.25.X. I tried renewing the lease on my PC (Ubuntu) expecting to get 192.168.1.X, but here is what happened: $ sudo dhclient r $ sudo dhclient eth0 (long wait) $ ifconfig eth0 inet addr:192.168.25.251 After a few minutes I renewed it again and it came with correct 192.168.1.81 (and from that point for now it is staying correct in every re-newal) Where from that anoth (HowTos)

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Submitted by u85500 on 02/26/2013

Stories similar to DHCP issue in our network, could it be hidden 2nd DHCP server?

I use dhcp in /etc/network/interfaces: auto eth0 iface eth0 inet dhcp No network-manager installed.

This makes the dhclient run with option "-1":dhclient3 -e IF_METRIC=100 -pf /var/run/dhclient.eth0.pid -lf /var/lib/dhcp/dhclient.eth0.leases -1 eth0 dhclient manpage: The -1 flag will cause dhclient to try once to get a lease.

EVN: F13, dhclient-4.1.1-15.fc13.i686 -------- My public interface (eth0) successfully gets a *real* public IP address from my ISP DHCP server; HOWEVER.....here's the issue:

- Valid public IP that the dhcp client gets from ISP is on 174.97.216.0 network.

I need to retrieve the DHCP option 130 from my DHCP server on a Windows 2008 server.

I managed to get it on linux with the following config :

/etc/dhcp/dhclient-eth0.conf :

option my-custom-option code 130 = text; request subnet-mask, broadcast-address, time-offset, routers, domain-name, domain-name-servers, host-name, my-custom-option;

Then in /var/lib/dhclient/dhclient-eth0.leases :

lease

I installed ubuntu lucid on my thinkpad x201i laptop.Recently I found it that when I connect my cable to my laptop in our school's library,my dhcp client can not obtain correct IP.I have to set it manually to :

Address: 192.168.0.223

Netmask: 255.255.0.0

Gateway: 192.168.20.1

DNS Serve: 202.119.32.6

When I run "sudo dhclient eth0", I got the following infomation:

Internet Systems Consortium

I have a Lucid 64bit server implementation. I appear to have two versions of dhclient3 running at all times as shown below. I wonder whether this is normal and if not if there is a solution to fix? As can be seen both instances are attached to the same interface i.e.

What I'm trying to achieve is to get cold-start, zero-state DHCP lease which means forcing dhclient through the full discovery and configuration process (DHCPDISCOVER–DHCPOFFER–DHCPREQUEST–DHCPACK as opposed to the shortcutted DHCPREQUEST–DHCPACK cycle which uses a remembered address).

My guest vm cannot get an ip address from my host it kept printing eth0: lease expired x seconds ago. I've tried to start dhclient -r and dhclient and restart eth0 to no avail, see here for more: http://www.cyberciti.biz/faq/howto-linux-renew-dhcp-client-ip-address/. How can I get a new lease in my guest?

Debian Squeeze as a router 46 weeks 1 day ago

I'm trying to setup Debian Squeeze (ala Dreamplug) as a router.

Hi guys,

Normally I connect to the LAN using my wifi connection on my netbook. Having said that, I don't remember the last time I used my eth0 connection. Now I just found out tonight that the wired connection is not working.

I thought it might be a hardware problem..