ISC DHCP is open source software that implements the Dynamic Host Configuration Protocols for connection to a local network. It is a reference implementation of those protocols, but it is also production-grade software, suitable for use in high-volume and high-reliability applications. DHCP is ...

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Can ISC dhcpd operate as a proxy dhcp server for PXE boot?

I have an existing LAN with a DHCP server already dishing out IP addresses. For various reasons I cannot replace that server so it will still need to dish out IP addresses. I've been experimenting ...
3
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1answer
201 views

Is there a match on incoming interface in DHCPd classes?

(Note, the title of the question Is there a way to classify DHCP requests based on the interface they're coming from? is what I want answered, but it doesn't actually ask that question for a ...
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2answers
787 views

isc-dhcp option82

I have a question about correct isc-dhcp configuration. I want to lease ip addresses to users based on switch port. For this I use DLink DES-3200 series switches. Everything works well, but recently ...
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1answer
3k views

DHCP: One NIC and multiple subnets

I'm setting up a Debian to work as a gateway for a small office network. I need to have three subnetworks for different areas within the company and I will define which PCs will get what IP based on ...
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1answer
282 views

Assigning DHCP subnets to users based on hardware

On our network, each user gets their own octet, eg Fred gets 10.2.105.0/24 and Barney gets 10.2.106.0/24. They get a laptop and a development server from IT with a known mac address. What I want to ...
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0answers
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ISC-DHCPD failover, Modifying host definitions via OMAPI

Background: I'm working on replacing my single DHCP server with 2 in a failover configuration. When I do a DHCP request I see the lease is created in both dhcpd.leases files on each server. However, I ...
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1answer
285 views

dhcpd: varying vendor-class-identifier

I'm having trouble selectively sending parameters in response to a DHCP Inform packet using groups (or even without, just using host declarations) for bootp stuff. My configuration file right now ...
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1answer
5k views

Fixed and dynamic IPs in ISC DHPD lead to double lease

I would like to have a small dynamic adress part and the most clients are assigned a fixed IP adress. My dhcpd.conf looks like this: use-host-decl-names on; authoritative; allow client-updates; ...
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2answers
4k views

Web interface for managing an ISC DHCP server

I am looking for a web interface to administer an ISC DHCP server. I have the setup of one Debian Linux box running an ISC DHCP server and I would like to add a second DHCP server as failover. To ...
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2answers
130 views

Is it possible to run pre-Lion OS X in an IPv6-only environment without static configuration?

Is it possible to run pre-Lion OS X in an IPv6-only environment without static configuration? From what I've been able to figure out, OS X 10.6.x will acquire an address via SLAAC, but it doesn't ...
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3answers
269 views

ISC-DHCPD: why does it cease to work when the internet is down?

For as long as I've been using a DHCP server on Linux or even FreeBSD (all come from ISC if I recall correctly), it seems that it just doesn't know what to do with DHCP requests when the Internet goes ...
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1answer
2k views

ISC-DHCP-SERVER - Can different reservations get different options (router, DNS, etc)?

Suppose there's just one Ubuntu / ISC-DHCP (v3) server on the network. I've successfully been able to provide "DHCP reservations" meaning MAC foo gets ip 1.2.3.4, whereas everyone else just gets an ...
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1answer
326 views

isc dhcpd: how to insert option 61 (client id) into dhcpoffer

I have a quick question. Is it possible to make ISC dhcpd server insert the option 61 (client id) in DHCPOFFER, in case if it is present in DHCPDISCOVER? The ISC dhcpd version I'm using is dhcp-4.1.1 ...
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1answer
814 views

Force windows 7 to update dns through dhcp server?

I have setup a new BIND9 to allow dynamic updates from my DHCP3 server. I am securing it using a DNSSEC key. Everything appears to work except when my windows workstation grabs an IP address it tries ...
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0answers
467 views

How to make forward domain name updates work with ISC dhcpd and Windows clients?

We have ~100 Windows 7 clients and are running dhcpd 4.2.2. We're running two daemons, one for IPv4 (DHCP) and one for IPv6 (DHCPv6). IPv6 clients correctly register under ...
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1answer
454 views

Is it possible to make ISC dhcpd (IPv6) 4.2.2 unicast-only?

I ask because the server is handling DHCPv6 for two VLANs and I can see some requests both via DHCPv6-relay from our ProCurve switch and via the ff02::0:2 anycast address and responds to both ...
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2answers
227 views

DHCP configuration problem

EDIT: We have following setup: User comes to building, he gets address from range for unknown clients (192.168.100.0/25) and can only get to our web site. We call it anonymous range. Let's say our ...
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3answers
14k views

How to configure radvd, dhcpd6, routing and /64 subnet based on delegated prefix by DHCPv6-PD server?

My ISP has just started IPv4/IPv6 dual stack service. In order to connect IPv4/IPv6 internet, almost all users usually use a CPE leased by the ISP. But I want to use my Linux router instead of such ...
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1answer
465 views

Is “broadcast-address” necessary in dhcpd.conf?

Or, more generally, is it required to specify the broadcast address that a client should use when a DHCP server is assigning an address?
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3answers
8k views

Exclude IP address from DHCP pool

Is there a way to exclude an ip address from dhcp pool? For various reasons i have a machine that I can't reconfigure or move off the network (lets call it a printer). It has been hard coded an ...
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3answers
2k views

modify dhcpd.conf via script to convert whole subnet to DHCP reservations

We have a hodgepodge of systems that are either static IP addresses, or DHCP reservations. (We don't hand out any addresses except reserved ones). Some servers have multiple Nics, and ILO cards. Its ...
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3answers
1k views

Monitoring an ISC DHCP Failover Status Using Nagios

I recently implemented ISC DHCP Failover and it's working beautifully, but I'd like to monitor the current status of the failover using Nagios. Ultimately, I would like my Nagios check to: report ...
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1answer
1k views

ISC DHCP server: how many IPs are in use?

I'm wondering what is the correct way to count how many IPs are in use in my network according to the dhcpd process. Is it just a matter of counting "binding state active" lines in dhcpd.leases file? ...
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2answers
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ISC DHCP - Force clients to get a new IP address, instead of the being re-issued their previous lease's IP

We are in the middle of a migration of our DHCP and DNS services from a Debian-based server to a Windows Server 2008 R2 implementation. The Debian server is running isc-dhcpd-V3.1.1. All of ...
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2answers
1k views

Is the native DHCP client for MacOS X able to send “Vendor class identifier” (opTag 60) in a DHCP request?

Is it possible for MacOS X (current version or in any previous one) to easily force DHCP client to send to DHCP server, at the beggining of the conversation - in DHCPDISCOVER packet - option "Vendor ...
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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 ...
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4answers
423 views

why would dhcp listen port 80

I have a CentOS server with isc dhcpd and apache 2 webserver running. A couple of minutes ago I have tried to restart apache: /etc/init.d/httpd restart Restart has failed with: Starting httpd: ...
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1answer
3k views

dhcpd, DISCOVER, “no free leases”

I am attempting to set up a VERY simple DHCP server. I am using Ubuntu 10.04, and I installed the "dhcp3-server" package. The server has one interface (eth0) statically set to 10.0.0.10(/21). I want ...
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6answers
3k views

DHCP server with database backend

I have been looking around for something to replace my (ancient) ISC-DHCPd server. A DHCP server with a database backend sounds like a great idea to me, as I could then have a nice, friendly web ...
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1answer
6k views

Windows 7 Failing Ping on IPv6 in DHCP Setup

I have set up a test ISC DHCP server that is not connected to an internet with DHCP and DHCPv6. I also have a Cisco 3750G with IPv6 enabled. I have firewalls off on both machines. My Windows 7 ...
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3answers
985 views

dhcpd won't let go of old leases

We have DHCP setup to hand out leases in the following range: 192.168.10.190 - 192.168.10.254 (roughly 65 leases) Our small business network only has about 30 computers that use DHCP. We noticed ...
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7answers
848 views

Audit reserved IPs for UNIX/Linux ISC-DHCP

Are there any good FOSS tools to do an audit of reserved IPs used in a Linux/UNIX ISC DHCPd environment? I'm trying to ensure that we do not have stale IP addresses reserved when old MAC addresses ...
4
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1answer
765 views

Windows 2003 DNS updates from ISC DHCP server

We have a very mixed network, with most clients being Debian Lenny, the rest Windows XP/Vista/7. The network itself is split into two segments (for technical reasons) called "corporate" and ...
0
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1answer
951 views

Accessing DHCP Client's vendor-encapsulated-options

In the dhcpd.conf file for isc-dhcpd-V3.1.1, I have set up a vendor options space and defined several different options. I am able to use those definitions to send options from the server to the ...
2
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2answers
736 views

Automatic subdomain wildcard for DHCP-DDNS additions?

I'm running dhcp-4.0.2 server and bind-9.6.1-P3. When a new Mac OSX DHCP client with the name "harry" connects to the network, the DHCP server gives it a lease, and adds appropriate A & PTR ...
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3answers
1k views

Where is dhcpd's syslog message formats documented?

I am looking at bunch of syslog messages written by dhcpd. I want to write a quick parser that can deconstruct the message into its component parts, but I don't know what the various parts mean. I ...
2
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1answer
3k views

How to ignore a set of Mac addresses in dhcpd.conf?

Is it possible in dhcpd.conf to ignore requests from a set of MAC addresses? Something like this: host vminstances { hardware ethernet d0:0d:*; ignore booting; }
8
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4answers
2k views

DHCP on-the-fly block assignment

We have a large number of clients who connect to our DHCP machine. We want to assign some of them to a different IP block, which is routed with lower priority. Every DHCP lease renewal, we'd like to ...
4
votes
3answers
1k views

A Linux DHCP server that will listen on an non-broadcast (tap) interface?

Are there any Linux DHCP servers that will listen to what Cisco calls an "unnumbered" interface, or what others might call a "NBMA" (non-broadcast) interface. I have a Linux system that connects to a ...
3
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2answers
5k views

Assign DHCP IPs for specific MAC prefixes

I'm running a ISC DHCPd server for my network serving a number of subnets. One of the things I would like to do is assign a specific range of IPs to hosts with a common MAC prefix (ex. 00:01:02). ...
2
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5answers
4k views

DHCP: Logging host declarations in log file

I am currently running ISC-DHCP server v3 on Ubuntu 8.04. What I am trying to do is log Who got what IP address when. Currently in the DHCP log file you can see the following: DHCPDISCOVER from ...
2
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4answers
3k views

Option 82 and dhcpd. “No free leases” for second computer

There is DHCP server in network (isc-dhcpd-server-3.0 on FreeBSD 7.2) than gives one IP per switch port to every user via Option 82 The problem appears when user disconnects one of his computers and ...