Dynamic Host Configuration Protocol (DHCP)

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2
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1answer
126 views

Microsoft DHCP server giving “old” lease to clients switching networks

I have 2 Windows Server 2012 R2 DHCP servers running in active/active load-balancing on one of the networks. DHCP requests from the other networks are DHCP relayed by the router to these DHCP servers. ...
2
votes
1answer
124 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
1answer
504 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 ...
2
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1answer
822 views

DHCP Server Issuing NAK when servicing multiple subnets

We currently have 3 VLANs setup in our network. On our DHCP server (Windows 2008) we have 3 scopes created for the 3 separate subnets. Our clients can't seem to pull addresses on the subnets, except ...
2
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1answer
308 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")...
1
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1answer
48 views

1-dhcp server for 2 separate network

Debian Server Setup (wheezy) 1 - eth0 - Connected to INTERNET 1 - eth1 - LAN 1 (Network 1 : 192.168.100.0/24) 1 - wlan0 - Access Point (Network 2 : 192.168.200.0/24) /etc/network/interfaces auto ...
1
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1answer
243 views

Workstations connected to SBS 2011 can not connect to “http://connect/” and are getting frequently disconnected or kicked off of the shared drives

Small Office, there are 7 computers and a server running SBS 2011. 2 workstations are not currently bound to the server, because after recently reinstalling windows 7 on them, it was discovered that ...
4
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0answers
3k views

DHCP Server Not Offering to PXE Client

DHCP Server Not Offering to PXE Client BACKGROUND: I'm in the process of adding PXE services to an existing SCCM 2007 server. The SCCM server is separate from the DHCP server (Server 2008 x86) and ...
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0answers
65 views

Did I cause this DHCP failure?

I asked this here, it was requested that I move it to this forum instead. I have a question that I need some counsel on concerning DHCP and what may happen in a certain situation. I have a case ...
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0answers
55 views

DHCP client not getting IPv4 address from a DHCP server

I configured a DHCP server on a VM in VirtualBox. This machine has 2 network adapters, enp0s3 - NAT (from where I have my network connection) and enp0s8 - Internal Network (intnet). DHCP server is ...
2
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0answers
174 views

How to associate a DHCP pool or subnet with declarations for a class

I have the following working configuration for ISC DHCP server 4.1.1, which hands out fixed addresses to registered clients. Some of those clients are configured for PXE booting (for FAI and SCCM). #...
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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-...
2
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0answers
873 views

DHCP offer is unicast but DHCPACK is broadcast

My DHCP server broadcast DHCPACK 0xffffffff . it is not working on layer 3 dhcp relay agent . as it can not forward this broadcast message to my client. can any one help me from exactly the broadcast ...
2
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0answers
354 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 ...
2
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0answers
235 views

dhcpd.conf rule-based mapping

We have ~100 physical nodes which can host a large number of VMs apiece. We need to set up dhcpd on one machine to distribute addresses in a predictable fashion based on MAC address. We'd like to go ...
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0answers
94 views

Can I configure ISC DHCP to issue the same fixed-address to every client?

I have a handful of devices which are normally in separate networks (or perhaps not even connected to a network), and they use DHCP to get their IP addresses. Now I would like to run some script on ...
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0answers
272 views

2008R2 DHCP Server Becomes Unresponsive

At the end of 2013, our single Windows Server 2008R2 DHCP server started becoming unresponsive once every week or so. The server itself was up, but the DHCP server was unresponsive. Attempts to ...
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0answers
120 views

dhcp relay with failover to local service

I'd like to set up a dhcp server which normally relays to a central site, but has a pool of addresses to hand out if the link to the central site goes down. I'm using isc dhcp server on Debian, but ...
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0answers
695 views

One server has multiple IP address leases but just one adapter and no dhcp reservations?

One of our servers' has multiple (10) DHCP Addressleases and I don't know why. The server itself has only one adapter and even if I execute ipconfig /all I only see one IP address defined. Even in the ...
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0answers
161 views

Access Denied DHCP Tool

I cannot figure out why this is happening, when opening the DHCP tool on my server, I get the following message. Access Is Denied You do not have access to this DHCP server. To view information ...
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0answers
62 views

force dhcp server to always run

I have an Ubuntu machine with two Ethernet network interfaces and on one of them I am running a DHCP server (isc-dhcp-server). I noticed that the server daemon stops running whenever I suspend the ...
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0answers
2k views

dhcping “no answer” on CentOS 6.4

I installed a DHCP server (yum install dhcp) and this is my conf: # create new # specify domain name option domain-name "mydomain.name"; # specify DNS's hostname or IP address option domain-name-...
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0answers
150 views

DHCP Requests out of line with lease time, inordinate amount of requests to server

Environment contains an OS X 10.6.8 Server with OS X 10.8.2 clients. DHCP is running on server with a lease time of 1 Day (86400 seconds). The system log is flooded with DHCP REQUEST/ACH messages ...
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0answers
144 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 ...
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0answers
1k views

DHCPD Offering ip address on wrong subnet

I just recently added a new subnet for our wireless network to our DHCP configuration for the 192.168.254.0 subnet. Most of the time when wireless clients connect it works just fine. However, ...
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0answers
568 views

dhcp-server with 2 subnet problem

How can I have 2 subnets (net1 and net2), one that alloweds all and the other only allowes selected hosts based on mac address? Here is my dhcpd.conf ddns-update-style none; log-facility local7; not ...
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0answers
21 views

DHCP server assigning same IP address even if Computer is connected in different VLAN

DHCP Server OS - Windows Server Standard 2008 R2 DHCP Client OS - Windows 7, Linux based OS etc.. I have configured DHCP Server on Windows Server Standard 2008 R2 with SuperScope. Let assume that i ...
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37 views

How to connect docker containers to physical local network?

I have a automation script which runs clusters docker containers which are need to be in my local network. Right now i am manually collecting list of un-used IP address in an array and i am poping out ...
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0answers
51 views

Use Windows RSAT DHCP Server MMC SnapIn with Linux Samba 4 AD to manage dnsmasq/isc-dhcpd

This particular Active Directory installation uses a Samba 4 Domain Controller Forest running on up2date (05-2016) Debian Linux Jessie VMs. Remote Server Administration Tools (RSAT) are used from ...
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0answers
53 views

dhcpd class match on hostname or mac address

We are running DHCPD 4.1.1-P1 on a RHEL 6 server. Currently we have 1 class defined for deny purposes. We now have a need for a class match to allow all devices that match a variable and deny ...
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0answers
16 views

Smaller subnet mask to “merge” VPN-connected LANs?

I have two LANs connected to different internet connections (in different cities, in fact): ISP1 -> LAN 1: 192.168.10.0/24 ISP2 -> LAN 2: 192.168.11.0/24 On each LAN is a router. Both routers ...
0
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0answers
42 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 ...
0
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0answers
27 views

Do DHCP server messages have to be sent from port 67?

I know DHCP servers receive messages (e.g. Discover, Request) at port 67. Can a DHCP server send responses (e.g. Offer, ACK) to port 68 from a port other than 67? I thought the client should not ...
0
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0answers
61 views

windows server 2008 R2 DC/ Dhcp server

windows server 2008 R2 DC/ Dhcp server. my workstations (windows 10 and windows 7) are having problems with connection. they are getting limited connection. the err they are getting on the work ...
0
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0answers
42 views

DHCP Server Dynamically Updating DNS on Other Server (Both Windows 2012 R2, No AD)

We have had a single Windows Server 2012 R2 server (with no Active Directory) running DNS and DHCP for our main network for a good few months with dynamic DNS updates from DHCP working fine. We have ...
0
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0answers
11 views

Unable to access VM after DHCPACK libvirt

The installation of a particular software makes my VM lose its connectivity. The point where it hangs is 2016-04-05 16:49:11.996 | Listening on LPF/o-hm0/fa:16:3e:b2:43:4c 2016-04-05 16:49:11....
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0answers
32 views

IPv6 Ping is unsuccessful when IP is obtained from DHCP server

I just faced this problem and it's driving me crazy. I have DHCP server for both IPv4 and IPv6. IPv4 works like a charm but the problem is IPv6. My client gets IPv6 (fc50::a9 to be exact) from DHCP ...
0
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0answers
36 views

dhclient bound to recorded lease even if no DHCP server is availabe

My Ubuntu machine is connected to switch and switch is connected to DHCP server(router).Now whenever DHCP server is down but link is available through switch it tries DISCOVER multiple times. But ...
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0answers
51 views

DHCP option 43 on switch Dell PowerConnect 5500

I have Dell PowerConnect 5524. Put SW01(config-dhcp)# option 43 hex f104ac1338fa got Option code 43 is not a valid HEX string. Strange. Its worked ok for me on Cisco device. Looking at User ...
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0answers
135 views

Force isc-dhcpd to disregard client hostname in ddns updates

I have the following configuration of isc-dhcpd-4.3.1: ignore client-updates; ddns-update-style interim; subnet 192.168.128.0 netmask 255.255.255.0 { use-host-decl-names on; update-static-...
0
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0answers
21 views

Can I use isc-dhcpd to provide an IP address based upon the request parameters?

I've got a dhcp request to be served with ISC-DHCPD: Gateway-IP 10.128.1.9 Client-Ethernet-Address 00:01:23:45:67:89 Vendor-rfc1048 Extensions Magic Cookie 0x63825363 DHCP-Message ...
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0answers
142 views

Why do our Windows 2012 R2 DHCP Servers lose reservations?

Windows takes our DHCP reservations, but does not know how to hold-on to the reservations. There is a history of this in Windows 2008 DHCP server, but the closest i could find for Windows 2012 R2 ...
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0answers
14 views

Rotate Gateways between DHCP clients

On a small factory we have 3 Internet Fiber Optic Modems, about 40 computers, 1 server running windows server 2003 with one NIC, and an unknown number of cellphones The server has DHCP, Active ...
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0answers
157 views

What would cause DHCP Scope to thinks it's full when it's not?

Our DHCP server is not allocating addresses on one of our scopes. Statistics seem to show it's full: However, I can see there are only 88 addresses in use. I can't see any errors in the system or ...
0
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0answers
1k 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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0answers
176 views

How to disable or turn off DHCPv6 on Cisco 3939B router?

I am trying to set up a Windows Server 2012 R2 Essentials server properly. I would assume it could also apply to non-Essentials also. i.e. Standard. DHCP for BOTH IPv4 and IPv6 MUST be turned off or ...
0
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0answers
102 views

Server 2008R2 DHCP Server not responding to Windows Clients

I have a Windows 2008R2 Server running DHCP Server, configured with a custom dll to assign IP addresses based on circuit IDs. Linux clients and pxe boots (using ipxe) recieve IP addresses from the ...
0
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0answers
950 views

CentOS DHCP server supporting multiple subnets on a single NIC

I understand that what I am asking has been asked a million times already. I think I have read just about every post I can find on the subject yet I still cannot get this to work. I have a DHCP ...
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0answers
73 views

DHCP Randomly Not Assigning Addresses

Having a strange issue for the past day or so. Some users (probably about a dozen, dozen and a half out of 100 or so) are having trouble pulling DHCP. They are getting the private IP address. If I ...
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373 views

Windows DHCP server not sending all options

I'm facing a strange problem with Windows Server 2003 and its DHCP server. Here is my scope and its related options. However when I look at the traffic using Wireshark, here is what the server is ...