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 ...
0
votes
2answers
35 views
ISC DHCP infinite lease time
How can i configure ISC DHCP server to infinite lease time for all clients?
man dhcpd:
Lease Lengths
DHCP leases can be assigned almost any length from zero seconds to infinity. ...
0
votes
0answers
32 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 ...
4
votes
1answer
94 views
How does broadcasting work on a server with multiple IPs?
Say you have two dhcp servers, A and B.
Server A has two IP addresses, 10.0.0.1 and 10.0.0.2.
Server B has one IP address, 10.0.0.3.
Server A has two instances of isc-dhcp running, one specifying a ...
2
votes
0answers
97 views
DHCPREQUEST and DHCPACK spam in logs
I've recently noticed that my android phone (droid dna, although the thunderbolt that I had before did the same exact thing) is rapidly requesting dhcp info my dhcp server (isc-dhcp-server on debian ...
0
votes
0answers
32 views
dhcp client brings down static virtual interfaces on renew
On a debian squeeze system my network configuration looks like this:
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet dhcp
auto eth0:0
iface eth0:0 inet static
address 195.1.2.76
...
0
votes
1answer
47 views
How to forward gateway requests for a subnet through another connection under Linux
I have a Debian machine acting as a DHCP server/NAT, connected via PPTP to another machine,connected to a subnet 10.0.0.0. How do I configure it so requests from clients on this machine for the ...
2
votes
1answer
36 views
Changing DHCPv6 server
I have a DHCPv6 daemon that is answering for requests of some machines and everything is working fine. So I decided to remove this DHCPv6 daemon e start another daemon on another server, but the ...
0
votes
1answer
500 views
DHCPDISCOVER/DHCPOFFER, but no DHCPACK
I have a remote client machine that is sending out DHCPDISCOVER's.
The server is responding with a DHCPOFFER, but there is no DHCPACK.
This repeats about every 30 seconds from the same host. Is ...
1
vote
1answer
198 views
How do I assign hosts to classes in ISC DHCPD?
Suppose I have a bunch of hosts set up like this:
host host2 { hardware ethernet 10:bf:48:xx:xx:xx; fixed-address 192.168.1.2; }
host host3 { hardware ethernet 10:bf:48:xx:xx:xx; fixed-address ...
1
vote
1answer
75 views
Can I run 2 dhcp servers when I use predefined host entries?
I have a very specific setup of servers which netboot off a san. All of them provide identical functionality. There are no other machines in this netblock.
Each machine boots from an iscsi image ...
0
votes
0answers
46 views
How to sort dhcpd.conf by IP address
I mantain a list of mac-ip addresses in my dhcpd.conf file like this:
# host1 - description
host host1 {
hardware ethernet 70:71:BC:1D:A9:66;
fixed-address 192.168.0.43;
}
# host2 - descritpion
host ...
0
votes
1answer
406 views
PXE boot linux. PXE-E51: No DHCP or proxyDHCP offers were received
I am trying to have an ubuntu box (192.168.10.9) acting as a PXE server, but i have trouble getting DHCP to work.
The PXE server is connected to a SOHO router (192.168.10.1) acting as a switch.
I have ...
1
vote
1answer
143 views
When does ISC dhcpd expire leases
When exactly does ISC dhcpd forget a lease that is not explicitly freed by the client?
Context: I am running an installation with many small pools (3 address) and it does not seem to cope well when ...
0
votes
0answers
29 views
Is there a way to configure dhcpd so that unknown hosts can only be discovered, not renewed?
I'd like to set up dhcpd, so that IP address lease renewal is restricted to known hosts, but discovery (for IP-less hosts) is available to any host.
Is such a configuration possible?
2
votes
1answer
124 views
isc-dhcpd static ip within range
I have a isc-dhcpd server with dhcp-range 10.0.0.10 - 10.0.0.20.
There is also a device connected with static ip 10.0.0.10.
What would happen when a client with dynamic ip connects to the network?
...
1
vote
0answers
76 views
How to make ISC dhcpd not log a specific hardware ethernet address (mac)
I have isc dhcpd v3 serving a local subnet.
I have installed a rogue dhcp server detector (dhcp_probe) which constantly sends dhcp requests. These requests are logged by the legit dhcp server, filling ...
0
votes
1answer
676 views
Replies to request coming over a relay goes to relay's internal IP, not to original request's source IP
Dhcpd running on Linux gets a dhcp request over dhcrelay which is
running on other remote machine.
Oct 6 10:09:46 2012 dhcpd: DHCPDISCOVER from 00:1e:68:06:eb:37
(oguz-U300) via 172.16.17.81
...
1
vote
1answer
906 views
Setting up ISC-DHCP server getting DHCPDISCOVER, DHCPOFFER constantly
Working on trying to setup a new server to run FOG on. I have setup the server to serve DHCP addresses only on eth1 and not eth0. I have installed isc-dhcp and bind9 on the server.
I cannot get a ...
1
vote
3answers
431 views
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
votes
1answer
149 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 ...
0
votes
0answers
177 views
error in start of isc-dhcp-server
I have this error
sudo /usr/sbin/dhcpd -6 -f -cf /etc/dhcp/dhcpd6.conf eth0
Internet Systems Consortium DHCP Server 4.1-ESV-R4
Copyright 2004-2011 Internet Systems Consortium.
All rights reserved.
...
1
vote
2answers
411 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 ...
3
votes
1answer
2k 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 ...
2
votes
1answer
231 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 ...
1
vote
0answers
160 views
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 ...
1
vote
1answer
158 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 ...
1
vote
1answer
2k 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;
...
2
votes
2answers
1k 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 ...
5
votes
2answers
116 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 ...
1
vote
3answers
194 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 ...
1
vote
1answer
959 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 ...
0
votes
1answer
181 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 ...
0
votes
1answer
669 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 ...
0
votes
0answers
352 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 ...
0
votes
1answer
334 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 ...
1
vote
2answers
207 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 ...
6
votes
3answers
9k 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 ...
3
votes
1answer
284 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?
2
votes
3answers
4k 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 ...
0
votes
3answers
1k 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 ...
2
votes
3answers
726 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 ...
1
vote
1answer
595 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? ...
1
vote
2answers
2k views
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 ...
2
votes
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 ...
1
vote
1answer
893 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 ...
1
vote
3answers
334 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: ...
0
votes
1answer
2k 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 ...
6
votes
5answers
2k 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 ...
3
votes
1answer
5k 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 ...
0
votes
3answers
639 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 ...
