11
votes
2answers
1k views

What are the possible issues in using very short DHCP lease time (< 1min)?

We have a network setup for a demo, which lasts about 15mn. Our DHCP server is configured to assign ~ 100 addresses (max number of simultaneous connections or our AP) ... but since people might come ...
4
votes
2answers
138 views

How can i locate rogue DHCP servers? [duplicate]

I am investigating some odd behaviour on a sub-net, where host registration doesn’t list some of the IPs that some users report having. Now that I’ve seen evince, i want to passively scan for the ...
1
vote
0answers
25 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 ...
0
votes
1answer
50 views

CentOS: DHCP Server and DHCP relay on same machine

eth0 IP: 192.168.1.100 Alias interface eth0:dhcp IP: 10.10.1.100 dhcpd.conf: authoritative; local-address 10.10.1.100; subnet 10.10.1.0 netmask 255.255.255.0 { range 10.10.1.10 10.10.1.50; ...
1
vote
1answer
83 views

isc-dhcp leases file never cleaned

When running isc-dhcp the leases file seems to grow indefinitely (several hundred MB). If I restart the isc-dhcp service, the file shrinks to 1.5MB. How can I have isc-dhcp flush expired records ...
0
votes
1answer
39 views

Failover DHCP Windows 2012

Is Windows 2012 failover DHCP (hot standby) compatible with Windows 2003? I'm not sure if it's enough to create a Windows 2012 DHCP server and configure failover options.
1
vote
0answers
57 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 ...
1
vote
0answers
37 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 ...
1
vote
0answers
74 views

Windows Server 2012 DHCP and OSX Devices

I've recently put together a small office network (around 20 devices) with an attached machine running Windows Server 2012. Our gateway router provided by our ISP was pretty useless and started ...
1
vote
0answers
185 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 ...
3
votes
2answers
417 views

Assign fixed IP address via DHCP by DNS lookup

Preface I'm building a virtualization environment with Ubuntu 14.04 and LXC. I don't want to write my own template since the upgrade from 12.04 to 14.04 has shown that backwards compatibility is not ...
0
votes
3answers
287 views

Superscope DHCP leases and configuration set up

Hello I wanted to see if someone could help with a network problem I am having. Right now we have a super-scope and scopes of 192.168.50.1 and 192.168.51.1, as of now both are activated but only ...
2
votes
0answers
419 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 ...
1
vote
1answer
94 views

Is there a limit to the number of DHCP scopes I can have?

Some context: Currently all devices in our remote sites are setup on 1 VLAN. We have 400 remote sites. A project wants to split our sites into multiple VLAN's which on the whole seems like a good ...
2
votes
1answer
150 views

DHCP Warning Sign Icon On Windows Server

I have a Windows Server 2008 R2 SP1 Domain Controller. I have the roles AD, DHCP, and DNS installed on this server. I noticed today that there was a warning sign on my IPv4 setting, but not on my IPv6 ...
0
votes
2answers
74 views

Multiple DHCP servers [duplicate]

In what circumstances should you configure multiple DHCP servers on the same subnet? My understanding of using more than one DHCP server is that your clients will use the nearest DHCP which could be ...
3
votes
1answer
2k views

Move DHCP Scopes to existing DHCP Server

We have a remote Domain Controller that is running Server 03'. I'm wanting to retire this box and move to the 03' box that we have locally. I was looking at this guide, but wanted to ensure that it ...
1
vote
1answer
120 views

Can Windows Server 2003 DHCP Server assign multiple IP Addresses to a single host?

I have Windows 2003 Server handling DHCP for our network. We use reservations to assign some hosts IP addresses. Is it possible for the server to assign a single host two IP addresses in different ...
0
votes
1answer
44 views

DHCPD: permanently leased IP being offered (twice) to random node and assignee

Greeting. On a small LAN (< 20 networked devices) with a cento6 5.9 server/dhcp-3.0.5-33.el5_9). I am configuring permanent leases thusly (dhcpd.conf, partial): range 10.115.64.60 ...
-1
votes
1answer
105 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 ...
-1
votes
1answer
128 views

2 DHCP Server it is possible to set a default server and a second

i have the following question (Problem) i have a AVM Fritzbox 7390 as WLAN Router and there is DHCP-service running with a range of 50 adresse. so far i works nice. Know i would like to have a PXE ...
0
votes
0answers
36 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 ...
0
votes
0answers
79 views

dhcpd set ddns-hostname from client supplied hostname

Basic issue: I'm trying to setup BIND and DHCPD. I have both working and the only problem is DHCPD cannot update BIND zones with names of dynamic clients (those without static leases). By trial and ...
2
votes
2answers
226 views

Static lease IP dhcp within dynamic range pool

I am using fedora 13. I want to statically bind a MAC to IP. Now the problem is if the IP is within the range pool, it may get allocated to some other host also. For that I use a tweak, where I ...
13
votes
4answers
1k views

Windows DHCP Server - get notification when a non-AD joined device gets an IP address

SCENARIO To simplify this down to it's easiest example: I have a Windows 2008 R2 standard DC with the DHCP server role. It hands out IPs via various IPv4 scopes, no problem there. WHAT I'D LIKE I ...
-3
votes
3answers
244 views

How to get machines to use a DNS without a fixed IP, which does not appear in the DHCP lease? [closed]

I have some machines on a network. This network has a DHCP server - which I have no control over, and no DNS server, i.e. the DHCP lease refer you to some ISP's server and do not serve IPs for local ...
1
vote
0answers
53 views

Multiple DNS mappings for a host via DDNS

I have a network in which DNS is automatically updated with a record for hosts when they get an address via DHCP (isc-dhcp-server & Bind configured with DDNS updates). The DHCP server is ...
1
vote
1answer
73 views

DHCP server not assigning IPs - Linux (CentOS)

I am having a main issue with the DHCP server. It is not assigning IPs and the dhcp.leases file is increasing in size as it is logging multiple entries for same IP. Started and stopped the service ...
1
vote
1answer
152 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
votes
2answers
118 views

DHCP/static IP nomenclature

I've just inherited systems administration for a small network, on which we have exclusive access to the first 128 IPs on a private virtual subnet. We have a DHCP server which binds IP addresses to ...
1
vote
1answer
127 views

HyperV Migration and DHCP Reservation

In my company network we've 2 HyperV-2012 host with DAS, every server has a DHCP reservation in the DHCP server (windows server 2008). Yesterday we've migrated (using shared with nothing migration) ...
1
vote
4answers
2k views

Computer gets IP from DHCP server but has no internet connection

I've installed an isc-dhcp-server on Ubuntu 12.10 and I'm trying to setup a DHCP server on a head node for six worker computers in the local network. The head node itself is a DHCP client receiving ...
-1
votes
1answer
90 views

Access Control Lists & DHCP

Please take a look at this image right here. In the image above you can see a virtual netwerk simulation program (CISCO Packet Tracer 6.0) where I'm trying to setup a network and secure it. However ...
4
votes
1answer
295 views

DHCP scope for a user class option

In Linux how can I set a DHCP server configuration which will lease IP addresses from scopes which are defined according to user classes. For example the following configuration leases IP addresses ...
-1
votes
1answer
113 views

DHCP messages in LAN [closed]

I run a Mac and release/renew my IP with: sudo ipconfig set en0 DHCP In wireshark I get the following with udp.port==67 as filter: Why are the messages sent from my computer broadcasted, but ...
1
vote
1answer
169 views

How to override the network DHCP Server settings to be specific to my own .conf file?

Basically, I have want to test out WPAD(Web Proxy Autodiscovery Protocol ) , PAC. But I would like to do it without touching the Network DHCP server. So, can you suggest a way in which I can achieve ...
1
vote
0answers
104 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 ...
2
votes
1answer
52 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 ...
1
vote
1answer
137 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
2answers
82 views

Assign IP range per switch?

Is it possible to handout IP ranges per switch with the use of one DHCP server? Example, i have 2 Swicthes (A & B). I like to: switch a => 192.168.1.50 - 192.168.1.75 switch b => ...
2
votes
2answers
77 views

Why is a computer on my network not resolving correctly?

I am running Windows 2003 Server with Active Directory and DHCP enabled. the machine: laptop1 receives the IP: 10.2.6.134 from the Windows 2003 DHCP Server. the machine name and IP does not show up ...
-2
votes
3answers
162 views

No route to host after changing interface to static ip [closed]

I installed a Linux (Ubuntu) server inside my home LAN, initially it's automatically configured to use DHCP interface. I'm connecting to this server from another computer using that server's hostname. ...
1
vote
1answer
760 views

Vyatta: how do I view up fixed DHCP leases settings?

I'd like to know how could I get the MAC-IP DHCP associations. I know that there is show dhcp leases but it only shows information about the active leases.
4
votes
1answer
2k views

Can not authorize DHCP server

I have run into a strange DHCP problem. The thing is the service is running, but the DHCP is not authorized. However, when I try to do it by right clicking, the option to authorize is not there - I ...
2
votes
1answer
618 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 ...
5
votes
1answer
1k views

Client not getting address from some DHCP server

I'm working on some embedded devices which should be connected to a large network (hundreds of devices) via ethernet and that should be configured using the DHCP protocol. What I'm experiencing is ...
0
votes
1answer
761 views

How could I fix “No subnet declaration for restart (0.0.0.0)”?

I have a DHCP service installed on my distribution, Backtrack 5 R2 (ubuntu 10.04) and it was working fine, but when I began to configure DNS it suddenly stoped working, how can I make it work again?? ...
0
votes
1answer
105 views

Setting up a small DHCP server for small network on windows server 2003

I am trying to set up a DHCP server on a Windows 2003 machine for a small network. I have used this guide[http://www.windowsnetworking.com/articles_tutorials/dhcp_server_windows_2003.html] to setup ...
1
vote
2answers
385 views

dhcpd pool exhaustion - What's the result?

I have a DHCP server that serves leases to several houndred, maybe up to a thousand, different clients on an average day. The pool consists of 242 IPs, and due to the highly dynamic nature of the ...
1
vote
1answer
126 views

Is using wildcards for hostnames in dhcp module of dnsmasq possible?

I want to have all machines with a hostname that starts with foobar- assigned an IP from a specific range with an infinite lease. All other machines should have a volatile IP. I did the following but ...