DHCP stands for Dynamic Host Configuration Protocol and is an auto configuration protocol used on IP networks and an extension of the Bootstrap Protocol.

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1answer
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Does my small network need a domain name?

My question is simple: does a small network need a domain name or do I just leave it empty? Here is the information on what is happening: I have a small network (30+ machines) that includes windows, ...
2
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1answer
4k views

IP served by OpenVPN doesn't take ipp.txt into account

I'm facing some troubles right now with an OpenVPN server an former colleague set up (I'm not too into it ATM). We're using OpenVPN for a private network of ~200 clients (to be more specific, only 15 ...
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1answer
1k views

Windows 2012 DHCP Failover: Scope refuses failover config Error: 20044

I have a scope configured on a Windows 2012 DHCP server (primary in a hot standby config) with two Cisco Vendor class options. I've added the Vendor class options, identically, to the standby server. ...
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1answer
15 views

Windows Server 2012 r2 standard with dual NIC + DHCP

Currently I have a physical host with Windows Server 2012 r2 standard installed and DHCP role enabled. In addition the physical host has two network interface cards. I am planing to connect the ...
0
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1answer
23 views

TFTP boot file download aborted during PXE boot up

I'm using OpenDHCPServer together with OpenTFTPServer in order to try out network booting. My problem is after acquiring IP address client starts downloading the boot file and halts. Message in TFTP ...
3
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3answers
42 views

How would a PCAP filter look like to capture all DHCP related traffic?

As I understand it, for IPv4 I would need to capture UDP port 67 and 68, ARP, ICMP echo request and reply, and for IPv6 I would need UDP port 546 and 547, all DHCP-related multicast addresses, ...
2
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1answer
19 views

Configuring DHCP server (Win 2012)

I am trying to do some basic testing of a DHCP server (Windows Server 2012). I'm trying to do all this testing from a laptop. The VM's are set Host-Only (or 'Private to my Mac' setting) To get ...
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2answers
2k views

Juniper SSG5 DHCP IP Pool is full. Unable to offer IP address to client

hope we have some Juniper guys around, I have configured a Juniper SSG5 as our main firewall/router the DHCP server set on interface bgroup1 to have a rang from 10.10.10.76 to 10.10.10.210 All ...
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1answer
1k views

dnsmasq(as DHCP server) isn't working in KVM+libvirt envirmont

I'm using dnsmasq as DHCP server in VM environment. But It didn't working. I disabled basic DHCP feature in libvirt. <network> <name>default</name> ...
10
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3answers
2k views

Windows DHCP server - distribute multiple default gateways?

I'm helping a client through the process of configuring a Windows 2012 DHCP server while migrating from Linux ISC DHCP. In the Windows New Scope Wizard dialog, there is an option to: ...specify ...
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0answers
15 views

“Add Server” in MMC not showing fqdn. Any ideas?

and Nothing is "broken" but my curiosity (and sadly O.C.D) has my wondering why when I add another server through MMC it doesn't show the fqdn of the "added" server, just the hostname. Tutorials ...
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0answers
12 views

dhclient: No broadcast interfaces found, but eth0 is up and broadcast

I'm experiencing a common problem with dhclient. But I wasn't able to find a clear solution to this problem. System: ReadyNas RN104 Stock Debian for armhf Just upgraded to Debian Jessie (now ...
0
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1answer
19 views

Why are DHCP request and acknowledgment messages broadcasted and not unicasted?

In 'Request' part of the DORA process, IP and MAC address of the DHCP server is known to the client (as the IP datagram sent in Offer has this information). So if the destination is known, why is the ...
4
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1answer
5k views

Can a DHCP reservation use an IP address in the exclusion range?

Windows Server 2008 R2, running the DHCP service. DHCP Scope: 192.168.1.1 - 192.168.1.254 Exclusions: 192.168.1.1 - 192.168.1.99 If a reservation uses an IP address in the exclusion range (like ...
0
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0answers
20 views

Ubuntu MAAS: PXE only booting two nodes at a time

I'm currently setting up an Ubuntu (15.04) MAAS (1.7) cluster for the first time. It seemed quite straight forward and I even figured out how to boot VMs running on vSphere, so I have a nice testing ...
0
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1answer
34 views

Why is my DHCP pool not working?

I'm trying to create a configuration and it's doing most of what I want it to do, but the DHCP pool isn't assigning addresses. Here's the config so far: enable config t hostname xxxxxx enable ...
3
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1answer
1k views

Windows 7 Client gets incorrect IPv6 Prefix Length

I am currently setting up IPv6 and DHCPv6 for Server 2008 R2 on my private network for testing. I was able to get DHCPv6 to work by configuring a static, then setting up the scope. I was also able to ...
60
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11answers
130k views

How do I find if there is a rogue DHCP server on my Network?

What's the best approach towards determining if I have a rogue DHCP server inside my network? I'm wondering how most admins approach these kinds of problems. I found DHCP Probe through searching, ...
3
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2answers
3k views

Force DHCP Reservation Updates to Secondary DHCP Server in Windows Server 2012 R2

I have setup and configured two DHCP servers on my private network in load balancing mode as outlined in the following technet article: http://technet.microsoft.com/en-us/library/dn338979.aspx Both ...
0
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3answers
1k views

Gateway gets stripped from DHCP Reply through OpenVPN tunnel

I have a bridged OpenVPN setup. This is my server config: port 1194 proto udp dev tap0 ca /etc/openvpn/easy-rsa/keys/ca.crt cert /etc/openvpn/easy-rsa/keys/server.crt key ...
0
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2answers
147 views

Using the VLAN of a bridged switch

In our building, we have 2, 6509 core switches, one for our company, and one for another. We have a vlan configured with a /30 which bridges the 2 switches. Both of us are on separate /16 networks. ...
0
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1answer
30 views

No internet access for client static ip on linux dhcp server

We are using a dhcp server configured with isc-dhcp-server on debian 8 in a small office network. The server has two network adapters one is connected to a pppoe modem and the other is connected to ...
0
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2answers
7k views

Cannot ping a VM from a Hyper-V host

I am facing a weird situation in my network environment. My infrastructure looks like this: I have a D-LINK DIR-635 acting as my default gateway (192.168.0.1) A physical Windows 2012 Server ...
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0answers
26 views

Event ID 1340 - DNS registration for DHCPv4 Client & DHCID has been denied (DHCP Name Protection)

Event ID 1340 warnings are consistently being logged on a Server 2012 R2 domain controller in the System log whenever Apple/Mac clients connect to the network. Here's a log example: Log Name: ...
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1answer
1k views

two domains, one LAN, two DNS server, 3 problems

Background: we have 150 users using AD on domain ABC. Windows 2003. that serverDC1 has a DNS, DHCP roles, and there is serverDC2 which is its live DNS backup. logs seem healthy. then we chose to ...
0
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1answer
23 views

request ip from dhcp

I'm automating a deployment on a vmware esxi host using some custom shell scripts and I would need to know in advance the IP this VM is going to get from a DHCP prior to it being installed. I know ...
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0answers
3 views

How to skip DHCP if no cable connected to ethernet in Debian [migrated]

My Bananian Linux is wasting time at logon trying to get a DHCP lease for eth0 interface which is not connected. Well, the extender cable is connected to it, but nothing is on the other end. I have ...
5
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4answers
12k views

Excessive DHCP requests in /var/log/messages: DHCPINFORM, DHCPACK and DHCPREQUEST repeated

I have a CentOS 5.5 system running DHCP for several subnets. In /var/log/messages, I'm seeing constant DHCPINFORM, DHCPACK and DHCPREQUEST messages. I don't understand why these requests are more ...
0
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0answers
31 views

What happens when “Auto state switchover interval” is less than “Maximum client lead time” in DHCP?

I was wondering what happens when "Auto state switchover interval" is less than "Maximum client lead time" in DHCP? The question was raised after reading definitions of MCLT & ASSI: Maximum ...
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4answers
906 views

When the internet is down, so is Active Directory?

I am setting up a business server for a small office use with 5 users / 5 devices or so. Nothing elaborate here. I've set up a SINGLE Lenovo TS440 server (single NIC) with Windows Server 2012 R2 ...
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1answer
28 views

Linux DHCP server to provide unique options to each DHCP request

I am running a DHCP server in CentOS 6.5 and in my network, 3 clients can issue an DHCP request. The host needs to send the address of the tftp server and also the name of a config file. The order in ...
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0answers
16 views

How to configure dhcp request witch option 82 on port 10067 of server?

I have snr2960 switch and i need configure dhcp request witch option 82 on port 10067 of server ? Switch is cisco-like, and i configure this: switch(config)#vlan 1 switch(config)#vlan 3 ...
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3answers
192 views

Rotating DNS servers specified by DHCP

I've got an OpenStack cluster running with about 200 CentOS instances and I've gotten a complaint from my hosting provider that the DNS traffic is getting to be too much for their servers. To address ...
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0answers
68 views

DHCP Server configuring

I've been configured DNS and DHCP on Windows Server 2012 correctly. But when I open the DHCP server from start menu and server manager, I get different result. When I run DHCP manager from server ...
2
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1answer
30 views

Is it possible to set a dhcp option 77 value in vsphere as a config parameter so vNIC ROM (e1000/vmxnet3) uses it during PXE?

I'd like to set a dhcp option 77 string value in vsphere as a config parameter on a vm or vm template so that the vNIC ROM (e1000/vmxnet3) uses it during the DHCP part of PXE. My goal is to have PXE ...
6
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2answers
2k views

Per-client DNS servers with DNSMasq

I am running TomatoUSB with DNSMasq to provide DHCP and DNS services for my local network. What I would like to achieve is to provide alternative DNS servers for one or two specific clients on the ...
0
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1answer
1k views

VLAN & WiFi & DHCP with Cisco SG200

I'm trying to configure a small business network with one Cisco SG200-26, a Linux server and two TP-Link TL-WA801ND. I have set up the APs to have two different SSIDs, Public and Staff, and have ...
2
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5answers
4k views

resolv.conf after reboot on CentOS 5.5 EC2 instance

I'm having trouble getting my CentOS 5.5 EC2 instances (both i386 and x86_64) to properly populate resolv.conf after booting. No matter what I do, I end up with the default EC2 resolv.conf: ; ...
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6answers
7k views

Why am I getting duplicate DNS entries for same IP address?

I have a system (SYSTEMX) that is connected to our network through a VPN. Periodically the VPN gets disconnected and SYSTEMX loses its connection to the network. When this occurs I usually easily ...
1
vote
1answer
25 views

Symmetric DHCP failover configuration

I have set up a DHCP server on CentOS 7. It runs beautifully, however due to business demands, we are expanding to another site far away. This gives us the opportunity to host a failover DHCP server ...
1
vote
1answer
2k views

Retrieving kickstart and other .img file in pxe remote installation in CentOS

I am trying to installation CentOS through pxe tftp installation. Installation starts but it fails to download image files from the http server. but file are accessible on the http server. Logs from ...
0
votes
1answer
39 views

Polycom phone not requesting DHCP offer

My Polycom IP550 phone is not requesting the DHCP address that my windows 2012 server offered it. I have done a wireshark capture on a mirrored port on our switch and you can see that the phone is ...
0
votes
1answer
12 views

is it possible to use cobbler using windows dhcp server or without dhcp?

I want to configure cobbler in my network but my network already managing by a windows 2k8r2 dhcp server. Is it any way to configure without dhcp server ?
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1answer
2k views

Client see Windows Deployment Services but still get “selected boot device failed” error

Like the title says I can't Windows Deployment Services working. The client laptop has an ethernet IP address of 10.0.4.94. On the secondary DHCP server I've set option 60 to PXEClient, option 66 to ...
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0answers
34 views

Setting up stateful DHCPv6 on Linux

I want to set up a DHCP server on my local network for IPv6 that issues addresses and further information like DNS/NTP and so on. From my ISP I got the IPv6 Prefix which I will refer to as in further ...
3
votes
4answers
17k views

PXE boot fails to get IP address via DHCP, but DHCP works when OS booted

I'm trying to PXE-boot a Cisco UCS C240 server to install a new OS over the network, but it isn't picking up an IP address via DHCP during boot. I get the "No DHCP or proxyDHCP offers were received" ...
2
votes
2answers
67 views

WiFi access point without internet access - iOS devices disconnect

I'm trying to configure a WiFi access point to offer a web service on the local network, without offering clients internet access. The web server has a fixed IP address (let's say 192.168.2.2) and for ...
0
votes
1answer
1k views

How could I fix “No subnet declaration for restart (0.0.0.0)”?

I have a DHCP service installed on my distribution, Backtrack 5 R2 (ubuntu 10.04) and it was working fine, but when I began to configure DNS it suddenly stoped working, how can I make it work again?? ...
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0answers
77 views

AD DC for domain could not be contacted

We are using samba4 on Debian 8 as a AD DC and isc-dhcp on another Debian 8 machine as a DHCP router. The problem is that if I set dhcp ip on a windows client I can't join the domain. If I add the AD ...
0
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0answers
18 views

Why Windows not get DHCP properly?

I have a VM that installs Windows Server 2008 R2 Enterprise. It configures both DHCPv4 and DHCPv6 clients. The VM locates on an isolated network, where a dnsmasq offers both DHCPv4 and DHCPv6 ...