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

learn more… | top users | synonyms

0
votes
0answers
19 views

Interface being deleted

I have a cluster consisting of CentOS6.5 and CentOS7 virtual machines. I've come across an issue where the network interface, eth0, is being deleted for reasons unknown and I'm looking for help on how ...
1
vote
0answers
16 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 ...
-1
votes
0answers
14 views

OpenWRT Chaos Calmer 15.05 DNS forwarding, custom DNS Server, DHCP option - nothing works [on hold]

Okay, so essentially I'm trying to only forward one very specific address over one of those geo unblock dns proxy services. Namely Pandora.com. Don't judge, I like their raido stations better than ...
1
vote
1answer
14 views

DHCP Relay agent not working

I'm quite new to the DHCP Relay Agent thing, but it seems to be best solution. So here is the deal: DHCP server (Win 2012R2) is at 10.0.3.1/24; ServerB (Win 2012R2) is at 10.0.3.3/24 and 10.0.2.1/24. ...
2
votes
0answers
27 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
votes
0answers
18 views

Abnormal DHCP Android device traffic cannot be identified

Hi Serverfault community members. I've been trying to identify the source of an abnormal broadcast traffic generated by some Samsung Android devices with no success, so I ask for your help. I have ...
1
vote
0answers
14 views

DHCP snooping on distribution layer stops cliens on access from getting ip address

Here is my topology: sw1(gi0/1 trusted port)->sw2(gi0/1 trusted port)->core-sw(gi0/1)->DHCP_server at the beginning i only configured sw1: ip dhcp snooping ip dhcp snooping vlan 18 int ...
1
vote
1answer
26 views

Why a computer in one VLAN cannot get an IP address from a DHCP server in another VLAN?

Can anybody please explain as to why a computer in one VLAN cannot get an IP address from a DHCP server in another VLAN by default? Why is there a need for a DHCP Relay Agent or an IP helper, they all ...
0
votes
1answer
10 views

Dhcp Classless Static Routes hook error

I have a dhcp server that hands network information to vms of mine. It works fine for centos6,7 , and debian 7 clients. However it fails for Debian 8 and Ubuntu 16.04 clients. For the ones where it ...
-3
votes
1answer
42 views

Can a computer on one VLAN acquire DHCP from another VLAN?

Can you please explain what needs to be done in order for a computer in one VLAN to get an IP from a DHCP server in another/different VLAN? (Yes if something is done and no if that something is not ...
-1
votes
1answer
44 views

How can I block access to the internet for static addresses?

I have a router on CentOS 7 which provides access to internet for several IP addresses, which are reserved at DHCP server. Other hosts are blocked. If someone put static address from the reservation ...
0
votes
1answer
33 views

DHCP renew fails with multiple subnets on same link

Our network currently consists of 3 subnets on the same link: 1.2.3.0/24 is the global subnet 10.1.0.0/16 is used for NAT (because there are far more than 200 clients) 192.168.0.0/16 is the "guest ...
0
votes
0answers
17 views

Restricting Source IP of DDNS Updates

Goal: For a non-Microsoft DHCP server to send dynamic DNS updates on behalf of non-Microsoft domain clients. Question: With a particular zone in a Microsoft DNS server configured for "Nonsecure and ...
1
vote
1answer
29 views

Multiple interface Red Hat 6 ISC DHCP Server sending Incorrect PXE next-server

My setup: Red Hat 6.7 isd dhcp server 2x networks connected (A and B) One DHCP pool configured on Network A When I had this server set up on a single network ("A") it worked fine, now that I added a ...
0
votes
1answer
55 views

DHCP unable to deliver offers over routers

I have the following network: PCVLAN10 -> SWITCH_LAN1 -> ROUTER_LAN 1 -> ROUTER_LAN2 -> SWITCH_LAN2 -> DHCP(ROUTER) I have set up subinterfaces on the routers, and allowed trunking on VLAN 10 on ...
0
votes
0answers
23 views

Browser autostarts when ethernet is connected. How? [migrated]

I plugged my Windows 10 laptop into a router from our new isp. We only got the fibre, no services set up yet (The fibre can carry phones, tv and internet) Immediately when I plugged the cable in, the ...
0
votes
1answer
58 views

How to get the connected wireless router's DHCP server not of another router's in the same network?

I have two internet connections and three separate wireless routers on the same network. The two dlink routers are serving one internet connection and the speedport the other internet connection. My ...
-1
votes
1answer
36 views

DHCP Configuration

Our network ran out of IP address on the current local subnet, so my boss requested our service provider to change our subnet from /24 to /20, it will give us more than enough IPs to assign to the ...
-1
votes
0answers
42 views

DHCP Server on Windows Server 2012 Essential [on hold]

We have 250+ users with static IP's. Going to deploy DHCP server in network by looking into growing numbers of devices in near days. I have one 2012 R2 Std. box which will be primary for DHCP ...
0
votes
1answer
23 views

How can I configure systemd.network DHCP server to distribute IP routes?

From this question I understand that I can use DHCP to distribute classfull routes. How to do it with the DHCP server embedded in systemd.network (if possible)?
1
vote
2answers
46 views

how dhcpd handles static IPs vs DHCP reservations

We have a RHEL 6.7 server for DHCP. I am needing some clarification on how dhcpd handles network addressing when someone wants a permanent IP address. Here is a sample config from one of our servers. ...
0
votes
0answers
25 views

DNS is not enabled for Local Area Connection

On Windows Server 2008 R2, I have an error saying DNS is not enabled for Local Area Connection with a red circled "X" by the right. In DNS I have Error 4013. I have restarted the Server, the static ...
0
votes
0answers
60 views

Traffic on eth0 despite denying it with iptables

Despite having an iptables ruleset which should not allow it - DHCP is working on eth0. Given the below information can anyone give me an idea of why? tap0 is not up (not that it should make any ...
0
votes
0answers
25 views

PFsense 2.2.6 static dhcp hostname blank

We are on pfsense 2.2.6 and we enable static dhcp for each mac address on each VLAN where dhcp is enable. DHCP is working good but when I enable static dhcp and leave the hostname empty and when I ...
0
votes
0answers
8 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 ...
-1
votes
0answers
20 views

dhcp reconfigure extension client's support

There is reconfigure extension for DHCP - RFC 3203(FORCERENEW), which also requires DHCP-auth implementation RFC 3118. Ubuntu by default is shipped with dhclient, does it support these RFC? and what ...
3
votes
1answer
47 views

Does a Windows host correctly interpret dnsmasq parameters?

I have a network of Windows 10 machines served (DNS and DHCP) by a dnsmasq instance on a Ubuntu server (Ubuntu 15.10, dnsmasq 2.75). The setup basically works (dnsmasq provides addresses and manages ...
0
votes
1answer
22 views

Identical DHCP leases, excessive dhcp traffic

Fresh install of CentOS 7, removed dnsmasq, installed dhcp server, iptables, webmin, apache. This is school and lot of switches and wifi (bridge mode) AP's connected to this router One network - ...
1
vote
1answer
46 views

Best way to connect dual SSID / VLAN wireless to Watchguard firewall

I'm currently sorting out our network so we can have new wireless access points with dual SSIDs, one for internal use and one for guest use. These will be setup so each SSID is on a different VLAN. ...
3
votes
0answers
18 views

Search option in resolv.conf getting overwritten by prepend statement in dhclient.conf

I have setup a DNS server for my department which is running FreeBSD 10.2. It is currently connected to the campus internet and receiving its address via dhcp, so /etc/resolv.conf looks like this: ...
-1
votes
1answer
54 views

Minimal requirements to firewall rules for running dhcpd server in linux container

I want to run isc dhcpd server in lxd (lxc) container. But it does not recive clients requests (DHCPDISCOVER, DHCPREQUEST) from clients without this rule: iptables -I FORWARD -m physdev ...
1
vote
0answers
23 views

Why was the previous authenticity of the host ignored?

I'm on Ubuntu 14.04 Desktop. I have just logged into other machine (Ubuntu 14.04 Server) using ssh in one terminal. I'm still connected. When I did scp in another terminal (opened earlier) to move a ...
4
votes
1answer
64 views

Windows Server 2012 Failover DHCP

I've been tasked with migrating from our current 50/50 scope resilient DHCP servers to new hot standby failover DHCP in Server 2012 R2. Built a test bed with the two DHCP server VMs and created a ...
0
votes
2answers
43 views

How to discard a DHCP request's old IP address (and provide a new one)?

I switched from a 192.168.0.0/24 network to 10.10.10.0/24. The addresses are provided by dnsmasq-dhcp. The switch went fine for all devices but one - a printer (called PRINTER). This printer was ...
-2
votes
2answers
31 views

Cisco 1841 Router from STATIC to DYNAMIC Configuration

Basic PC-to-Internet Ethernet Configuration I'm trying to find the proper configuration in the IOS to have Fa0/0 = DHCP and Fa0/1 = STATIC-only, to allow packets from the STATIC side (inside network) ...
1
vote
1answer
21 views

DHCP removing existing DNS records when asked for leases and none are available

I'm having a problem with my Dynamic DNS and DHCP setup where clients requesting leases when none are available causes a cascading failure where existing clients have their forward and reverse DNS ...
1
vote
2answers
25 views

DHCP issue with Cumulus and ESXi

So my switch has Cumulus Linux running on it and I have ESXi running in my network. So my main network is on 172.22.0.0/24 which has my my esxi. The networks I want esxi vms to run on is ...
0
votes
0answers
16 views

Linux clients get DHCP, Mac and Windows clients does not

I'm a sysadmin for a smaller computer lab (~40 clients and ~2000 users). We are, since this fall, seeing some weird issues with DHCP within our network. The server receives a DHCP discovery from the ...
1
vote
2answers
55 views

Microsoft DHCP only for reserved addresses

We are runing a Windows Server 2012 DC which also takes care of DHCP. Now I want to limit the DHCP-Server to all the reserved hosts to prevent DHCP leases for foreign devices as laptops, ...
1
vote
2answers
202 views

How to have a Windows-PC registers it's name on dns server automatically

If I'm correct (please correct me if I'm wrong), a Windows-PC's name on a local network is not published via DNS but via WINS. Now let's assume I have a network with Windows workstations and I'm going ...
0
votes
1answer
48 views

Changing openvpn dhcp pool

I have a config at the moment which is working almost fine until some clients connect, the server starts to kick the clients off from the server or something like that. As I have checked every clients ...
0
votes
0answers
19 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 ...
2
votes
2answers
92 views

Non-secure DNS server - Allow dynamic updates only from DHCP server

I have a standalone DNS server configured for "Secure and Non-Secure" dynamic updates. I also have the DHCP role installed on the same server. How do I ensure that only the DHCP server can update ...
0
votes
1answer
55 views

Possible to configure DHCP server to only hand out IP's to PXE clients

Is there a way when you are setting up a Red Hat DHCP server for PXE boot to ONLY hand out IPs to PXE clients? We already have a Windows DHCP server on the network (a server which we do not manage)and ...
0
votes
0answers
32 views

TFTP open timeout with ip helper

I'm setting up a DHCP / TFTP server for server provisioning via PXE. I have two hosts on the same segment (10.1.1.0). One hosts boots, gets its IP, and is able to pull the pxelinux.0 image over ...
0
votes
2answers
40 views

ISC DHCP Client keeps asking for address

All of a sudden the network at my University has frozen and we managed to isolate the problem to massive amounts of UDP packets sent on the DHCP ports. On closer inspection, we found that some of the ...
0
votes
1answer
57 views

How to make a primary scope and secondary scope on DHCP server?

I am changing network structure and part of that is to change ip from 10.10.111.0 /24 to 172.16.0.0 /16 range. Now I need to have DHCP ready first in 172.16 range. I have two DHCP scope on a single ...
0
votes
0answers
37 views

DHCP not working for new pool

I created new dhcp pool(41 pool) in Windows server 2012 called vlan 41,routed with default gateway in router, added interface vlan 41 on core switch 3650, given ip help address as server address. I ...
0
votes
1answer
67 views

dnsmasq proxy mode and efi boot

So, I already have DHCP server in my local network. But I want to setup new VMs with network boot (PXE). I've setup dnsmasq in proxyDHCP mode to provide PXE info to booting clients while using other ...
0
votes
1answer
44 views

Does a Linux DHCP server have IP conflict prevention?

Scenario: We are migrating DHCP off our Cisco gear and onto a Red Hat 6.7 server. I am concerned about clients who will not release and renew for several days. Since the new server will not have any ...