2
votes
0answers
38 views

How can i prevent TINC from relaying DHCP

I am running tinc in several NAT routers running Debian 7 Wheezy, the VPN works fine for months, except because i've set it up in switch mode it relays DHCP requests and answers over all the VPN. The ...
0
votes
1answer
32 views

DHCP wont release allocated IPs [closed]

I have a TP-Link td28151 router and I am using DHCP. I need to connect 40 devices to my router by Ethernet. I have set the count of my clients to 100, and my subnet mask is 255.255.255.0. I have ...
0
votes
0answers
264 views

CentOS 6.4 - Cant get an IP from DHCP

I have a Ubuntu and CentOS system running on XenServer. The Ubuntu Box gets and IP from DHCP no problem. The CentOS will not take a DHCP but a static address works fine. [root@XenCentOS ~]# service ...
0
votes
0answers
203 views

How to filter out/disable DHCP NAK responses?

We have some crappy situation where we don't have control over the existing DHCP server on the network and where we need to add another BOOTP/DHCP server with the authoritative directive. Our ...
1
vote
1answer
2k views

DHCP reply packets do not make it into KVM instance in OpenStack

I'm running a KVM instance inside of OpenStack, and it isn't getting an IP address from the DHCP server. Using tcpdump, I can see the request and reply packets on vnet0 of the compute host: # ...
3
votes
1answer
272 views

NAT box load-balancing with iptables and 4 DHCP uplinks

I am trying to configure a router which provides Internet to a couple hundred users. This router has 4 basic cable uplinks at its disposition, which all use DHCP and have a capacity of around 10/1 ...
0
votes
2answers
738 views

Internet slowed down because of SQUID Server setup

Recently I have setup a squid server for our office. I have computer (A) with two ethernet cards, one for internet and the second one for local networkIt has Ubuntu server OS with squid-server and ...
0
votes
1answer
150 views

Can not ping a particular IP

I am allocating IPs to 2 VxWorks based machines simultaneously using OpenDhcpServer, the machines send the DHCP request upon powering on. The server allocates the IPs, but I am not able to ping the ...
2
votes
3answers
463 views

Disable static IP addresses on desktop computers

Is there any way of not allowing users to statically set an IP address on their machines? We have a lot of servers with static IP addresses and also a DHCP server. I am afraid of allowing users to ...
0
votes
1answer
67 views

iptable issues?

Currently I'm trying to setup a PXE server to boot Ubuntu 10.04 on clients. (See Issues with PXE setup on Ubuntu 10.04 DHCP/NFS Server for more details) I'm trying to mount basically the entire ...
2
votes
1answer
805 views

unable to block DHCP and other traffic on INPUT chain

Here is the output of my iptables-save command. The last rule and default policy is to DROP any packets that dont match any thing. Generated by iptables-save v1.4.9 on Wed Aug 3 21:00:05 2011 *filter ...
0
votes
1answer
198 views

Debian Stable - Routing problem

ADSL Router: Cisco 877 (172.16.0.254) PC1 (172.16.0.10) to port1 of router PC2 (172.16.0.20) to port2 of router Server, 2 NICs, eth0 to port0 of router. (172.16.0.240) Everything is OK with the ...
5
votes
2answers
1k views

Two DHCP Servers, Block Clients for one of them?

I am building out a kickstart network that resides on a different VLAN uses its own DHCP server. For some reason, my kickstart clients kept getting assign IPs from my primary DHCP server. The way I ...
1
vote
1answer
2k views

DHCP request error. Send_packet now permitted, How to debug, What does it mean

I recently installed CSF firewall and have made live a new server which is accepting around 600req/second. Its basically a reverse proxy and I found in pingdom and munin that for a particular time, ...
1
vote
1answer
1k views

Iptables - Allowing only a single dhcp (relay) client

I am trying to create a firewall rule on an Ubuntu 10.04 server running isc-dhcpd. I only want dhcp to be accessible by a single relay host (172.1.1.1). I have iptables set up like so: # iptables ...
5
votes
2answers
7k views

IPTables and DHCP questions?

On my other thread I was talking about some interesting things about the iptables policy and states, now I would like to understand more about how the DHCP works and how iptables understands it. ETH0 ...
0
votes
5answers
2k views

Querying a DHCP server in C#

I have a really large network. Class A network and due to security reasons broadcast and any other PING has been blocked. I want to get all the PC IP that are alive. Is there any way to query DHCP ...
0
votes
3answers
788 views

Port forwarding using IP Tables

I have a server with a LAN facing address of 192.168.5.100 (eth0) and another LAN facing address of 192.168.6.6 (eth1). On this server I have a Virtualbox instance of fedora running an apache ...
1
vote
3answers
230 views

2DHCP servers on 1 network

I have 2 pfSense routers setup. one is DHCP for 172.16.2.x and one is DHCP for 172.16.1.x. PC0 is 172.16.1.245 and I can ping PC0 from the (PC1) on the 172.16.2.x subnet. PC1 is 172.16.2.245 but but ...
0
votes
2answers
2k views

Port forwarding with iptables and dhcpd

The setup: I have a Linux (Gentoo, if that makes a difference) box that serves as a gateway for the whole apartment. This box does its NAT-magic with iptables and dhcpd. The problem: I have a certain ...