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0
votes
1answer
17 views

DHCP leases file has 200+ instances of the same lease?

I'm not sure what's going on here. I have a CentOS 7 DHCP server, and the leases file is growing at a linear but steady rate - it's re-issuing the same lease to the same MAC over and over again, and ...
0
votes
0answers
53 views

How to configure isc-dhcpd-server to update reverse zone without client pre configuration?

I'm trying to set up isc-dhcpd-server from ubuntu 16.04 (4.3.3-5ubuntu12) to configuring heterogeneous network with ubuntu, windows, macos, other ip devices. I'm already setuped bind to store ip ...
1
vote
0answers
20 views

“match hardware” in dhcpd.conf not working

I've been trying to get mac addresses with a certain OUI into a certain address pool. I haven't been able to get it to work at all. Here is a snippet of my dhcpd.conf and how it's applied. class "...
1
vote
1answer
145 views

How can I clear the DHCP GUI in OSX Server? Ghost clients in the building

I have a few client machines showing up in the network (not only in Server.app but also in various logs), which have "Computer Names" (Bonjour names in Apple-speak) which I don't recognize, but ...
0
votes
0answers
38 views

dhcpd.conf options for different subnets when layer 3 switch is doing the routing

We have a flat networks in our offices and I have been tasked with creating new vlans to compartmentalize traffic. Our current network is 10..0.0 (default vlan on our switch) with a CIDR of /24, ...
0
votes
0answers
62 views

dhcpd.conf — one-lease-per-client statement having no effect

I have read on this and this man page that the one-lease-per-client true statement in my dhcpd.conf will stop duplicate leases to a single client. However, I am still able to sustain multiple leases ...
0
votes
1answer
255 views

dhcpd not offering reserved static IP returns unknown lease

typically when I reserve an IP for a MAC addr the device when booting up and requesting a dhcp address, will pick up the address I reserved. However recently the request looks like it comes in but ...
0
votes
0answers
127 views

ASUS RT-AC66U WiFi Unit is blocking LAN DNS/DHCP Server

I'm using an ASUS RT-AC66U for WiFi. Decided to break out an old server to handle DNS/DHCP for local experiments. The problem seems to be that the RT-AC66U is (somehow) blocking the DNS Server. ...
0
votes
1answer
82 views

fedora dhcpd name server configuration

I'm having a hard time configuring a more modern release of a Fedora DHCP service to replace an older one and the problem is that clients aren't getting the appropriate DNS server information. I had ...
3
votes
2answers
2k 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
321 views

Client getting wrong option from DHCP server

I'm setting up a machine to load a Debian intallation with PXEBoot, following the guide on the Debian Wiki. I have the boot image sitting on a server, pxe.example.com, at /var/lib/tftpboot/debian-...
0
votes
1answer
242 views

dhcpd.conf for PXE/BOOTP boot not working

I'm trying to configure the dhcpd.conf file so that when I boot through the network using PXE / BOOTP, a bare metal server or a virtual machine (KVM) would get an IP address in the 10.0.2.100 to 10.0....
0
votes
1answer
286 views

Cobbler/TFTP: No filename or root path specified, but why?

I've installed a new Cobbler server and configured it as a DHCP /TFTP server. I've configured the /etc/dhcp/dhcpd.conf like so: [root@centolel ~]# cat /etc/dhcp/dhcpd.conf ddns-update-style interim; ...
2
votes
2answers
346 views

Release dhcp lease after forcing client to disconnect

I configured a wifi access point based on OpenWRT to limit the number of clients to 4 at the same time. For that purpose I gave a limited number (4) IP addresses leaseable by DHCP. After a period of ...
1
vote
1answer
33 views

Obtaining the running config for dhcpd

Is it possible to obtain the current running config for dhcpd? I inadvertently wiped dhcpd.conf but have not yet restarted the service. It is currently assigning the correct IPs to my test ...
0
votes
2answers
498 views

How to block DHCP traffic using iptables

First let me describe my environment: There is a VM (CentOS) acting as a gateway The gateway VM has to NICs, eth0 connects to public network, eth1 connects to private network eth0 get IP from public ...
1
vote
1answer
110 views

DHCP with fixed IP hosts (Ubuntu)

I'm managing an office system that assigns IPs based on the MAC address. The fixed hosts are added in a dhcpd-hosts.conf file which is included in dhcpd.conf. There are some PCs that are not in the ...
0
votes
0answers
69 views

How can I assign an IP by UID in DHCPd

Here was answered how to assign an IP by MAC address. I want DHCPd server to assign IP by UID. Can i just add record to dhcpd.conf in the same manner? For example: host example { uid 00:...
1
vote
0answers
413 views

Restrict hostapd wireless client from talking to eachother

How can I keep a wireless client of hostapd from talking to a wired client on the same network or another wireless client on the same network? Here's my network topology: [wired client] --> [...
1
vote
0answers
175 views

Assign IP not defined in a subnet range dhcpd [closed]

I look to deploy a DHCP server for a network of VMs that spread over various subnets. The DHCP server will not be used to assign dynamic ranges, but only static IPs based on the host MAC address. Is ...
2
votes
1answer
126 views

2 client classes sharing the same subnet range

basically I would like to achieve the followings: using only one subnet different types of user sharing this subnets creating 2 pools accordingly an user class called "l2vpn_user" if matched by MAC ...
2
votes
0answers
67 views

DHCPD does not allow filename option with a colon in it

For some reason, tftpboot does not work with a colon in filename parameter: group { filename "node7:linux/pxelinux.0"; host machine_7a { hardware ethernet 02:01:02:02:01:11; fixed-...
-1
votes
2answers
466 views

OpenBSD ISC-DHCP IPv6 not working?

How to enable dhcp for ipv6 in OpenBSD 5.5. Default dhcpd don't know about IPv6, it says that option -6 is incorrect and do not understand ipv6 config. But it has version 4.X that IPv6 must be enabled ...
1
vote
1answer
415 views

ISC dhcpd dynamic bootfile-name. Is this possible?

Actually I want to dinamically assign bootfile-name based on clients MAC. I have tried this config: option bootfile-name concat( binary-to-ascii(16, 8, "", substring (hardware, 1, 6)), ".cfg"); ...
2
votes
1answer
522 views

Cleanup DHCPD leases as well as DDNS Entries

I have a fairly simple set up on a Debian server I'm running. I currently have isc-dhcp-server installed along with bind9. I set up my zone and my reverse lookup zones and set up dynamic updates, it's ...
4
votes
0answers
97 views

Assigning option based on class membership inside the subnet section

We are looking for a way to do something along these lines in the dhcpd.conf file: subnet ... { #couple of options for the subnet here pool { allow members of "class-name1"; ...
2
votes
3answers
2k views

Fixed dhcp host to automatically expire any lease

I have the following situation: Multiple offices with multiple firewall/dhcp servers. Every time the IT team of some office plugs a new network printer i need to create a fixed-address entry, and ...
0
votes
1answer
756 views

ISC DHCP Server scope error

Why am I getting the following error after modifying my dhcpd server config? option space definitions may not be scoped
2
votes
4answers
13k views

How can I assign an IP by MAC address in dhcpd

How do I assign an IP address specific to a mac address using dhcpd? So far I have tried host blah { hardware ethernet <mac address>; fixed-address <ip address>;} in my dhcpd.conf. But ...
1
vote
1answer
550 views

How can I configure dhcpd to only update the reverse zone in bind?

I've got dhcpd pushing updates to bind, and it seems to be working fine: named[24161]: client 192.168.10.1#59141: signer "dhcp_updater" approved named[24161]: client 192.168.10.1#59141: updating zone ...
1
vote
2answers
2k views

Linux dhcpd server with multiple scopes to assign IP based on request source

I have configured a Linux dhcpd server with multiple scopes on the same interface(eth0). The devices which needs these IP address(DHCP clients) are on two different remote networks. The networking ...
2
votes
3answers
1k views

DHCPD clean leases on client disconnect

Is there a way to force ISC DHCPD to trigger expire or release for static lease right after client disconnect? I want to trigger a script right after client connects ("on commit" DHCPD event) and ...
-1
votes
1answer
436 views

Enterprise DHCP server solution? [closed]

I have a network of about 1000 assorted devices, all of witch are running by static IP addressing. Given the size of the network and the lapse of technical advice, the addressing scheme is in chaos ...
3
votes
2answers
7k views

DDNS, BIND and leftover .jnl files

I have configured BIND and ISC DHCPD to work together (using keys for updates). Now it's not that it does not work at all: forward maps etc are most often added. However, very often, for no apparent ...
1
vote
3answers
1k views

dhcpd not pushing ddns updates to bind

BIND and DHCPD are configured but as far as I can tell DHCPD makes no attempt to even send Dynamic DNS update to BIND. I can manually add records using nsupdate with the same key I have configured ...
0
votes
1answer
663 views

dhcpd update bind dns server on non standard port

I have most of a dynamic dns set up working. I can manually update the DNS entries using nsupdate and my dhcpd.conf file will attempt to set the DNS entries. However this fails as I don't have bind ...
0
votes
1answer
170 views

Pass kernel boot parameters from dhcpd.conf for a host group?

Is it possible to configure dhcpd.conf such that a specific host group would use an additional kernel boot parameter passed on to the kernel loading? Thanks!
2
votes
1answer
320 views

Cannot assign IP address according to an option parameter

I have this DHCP conf file: authoritative; option domain-name "XXX.XXX.XX"; allow bootp; ddns-update-style ad-hoc; class "karpuz-kabugu" { match if (substring (option user-class, 0, 6) = "karpuz")...
0
votes
2answers
1k views

Cisco ASA5505, packet trace shows bootps and bootpc traffic is dropped on DMZ interface

As the title already states, I have a problem getting DHCPd working on the Cisco ASA5505 version 7.2 with ADSM 5.2 with the basic license. Its an older one I know, and every time I tend to forget how ...
1
vote
1answer
2k views

how to force isc-dhcp-server to attribute new ip regardless of client mac address?

i need to serve DHCP requests for a given test tool tailored for a specific network hardware (hardware under test). The testing tool (my server + simple netgear 5ports switch) seems to work as long ...
1
vote
2answers
2k views

Is is possible to configure ISC's DHCPD to configure resolv.conf options like timeout and attempts?

The resolv.conf supports a line called options that allows for some fine tuning of the behavior of the resolver. In my environment we are using ISC's DHCPD to provide DHCP services to our services. ...
1
vote
1answer
89 views

set search domain on dhcp server without changing domain name

Suppose my company's domain is "company.com", our department's domain is "dept". How to set dhcp server in order to let our department's computers to search company.com? Or I have to set up a dns ...
8
votes
4answers
21k 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 ...
4
votes
1answer
11k 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 192....
0
votes
2answers
2k views

Switch sending DHCP packets to wrong VLAN

I have a basic remote site with a Cisco Catalyst 2924XL switch. There are 2 VLAN's at the site: 1 Default 2 Wireless There is a single server connected via a single ethernet cable, VLAN 1 is native/...
2
votes
0answers
5k views

Setting Shoretel phone time correctly with dhcpd

Our Shoretel 230 phones are not picking up time service correctly and thus, the time on the display is wrong. When I go to the diagnostics of the phone, they are using a wrong time server (old). Here ...
0
votes
1answer
180 views

overlay DHCP pool on top of exiting network

I have a network that was all statically assinged in the past, moving it to DHCP. Some hosts, we have as reservations, but not all of them.. Our server is running bind dhcpd on cenotos 5, with ...