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The Dynamic Host Configuration Protocol (DHCP) is an auto configuration protocol used on IP networks and an extension of the Bootstrap Protocol. DHCP allows for computers to be configured automatically to communicate with each other over an IP network without the need for manual setup by a network administrator. The implementation of DHCP relies on a DHCP server to hand out network configuration information to DHCP-capable clients that request an IP address (and other information required or useful in communicating with other devices on an IP network). In addition to an IP address, common configuration information served over DHCP includes a default gateway, subnet mask and DNS sever(s).

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We have a domain controller running Windows 2012 Server and it's also our DNS/DHCP server.  Non Windows devices acquire a DHCP lease, but fail to register in DNS.  Yesterday I added a non Windows device to the network, which immediately showed up in DHCP, but not in DNS.  This morning it finally did show up in DNS.  I added another device today and change the scavenge setting to 1 hour, but it still does not register with DNS.  I do have it checked to dynamically update DNS.

Maybe it tomorrow it will magically show up in DNS, but shouldn't it immediately be added to DNS when a DHCP lease is created?  How can I get this to happen without manually add it?
0
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All,

I have a project to use DHCP on Servers.  Has any one done this in their environment, any issues or risks?

Thanks!
0
I migrated my DC from 2003 to 2012 R2 recently, and have been having a real bear of a time with workstation connectivity. 2003 had a clean demotion(so it seemed), I exported/imported DHCP, synced DNS, and seized FSMO properly. I have looked through ADSIEDIT to see if there were any stale records of the old DC. There seems to be something funky with DNS and/or DHCP, as I am receiving event ID's 5781 NETLOGON, and 4013 DNS-Server-service, 1054 Group-Policy, and 10020 DHCP-Server warnings/errors.
These events are occuring when reboots are not even happening. Just all day long.
On Event ID 10020 DHCP-Server warning, I do not have iipv6 enabled on my NIC. All other NIC's disabled. ipconfig /all shows no ipv6 IP address.
Workstations are consistently and intermittently loosing connection to internet with Event ID 1014. This does not occur at the same time for workstations.
What I have done so far...

I have disabled all Windows software firewalls.
My DC points to itself as the DNS server.
DCDIAG reports no errors. (also with /test:DNS)
Have disabled slow link detection on workstation GPO and DC GPO.
Disabled autotuning.
Disabled task offload on DC
Created a _msdcs zone in the root of Forward lookup zones.

This is a solo DC. Solo DNS (active-directory integrated)
Forwarders point to my ISP which is Google. (8.8.8.8, 8.8.4.4)
I have not tried disabling recursion, as I don't really see that as a troubleshooting resolution for this problem.

After migrating the …
0
Hi,
We have:
SCCM 2012 R2
DP in remote office with PXE options enabled (VM within HyperV)
DHCP is on a Cisco switch
Option 66/67 set on the switch, option 66 ip [address] & option 67 ascii smsboot\x64\wdsnbp.com

When we try to do a PXE boot it displays the following error: PXE-E32: TFTP open timeout, see screenshot attached.

We use to have DHCP on the physical server at the remote office and that was also the DP and this worked fine. Since moving the DP to a VM and the DHCP to the Cisco switch it is no longer working.

Thanks
IMG_20170614_122728--003-.jpg
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I recently concluded a successful domain migration from windows Server 2008 to Windows Server 2012 R2 Essentials.  The new server is acting as a DC and is operating well.

However I have a problem Adding roles and Features.  I tried installing the DHCP Role on 2012 in order to migrate DHCP from 2008 but I keep receiving the following Message:

"The Request to add or remove features on the specified server failed.  The operation cannot be completed because the server that you specified requires a restart""

It does not appear to matter which role or feature is selected   The result is the same and numerous restarts have not resolved the problem,  

Has any one come across this problem before and resolved it?  Many thanks
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Server is domain controller in cloud, connected via VPN
Server is recently migrated - 2008 on premise to 2012 in cloud.

DHCP is running on local Cyberoam router
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Which VLAN   to enable ARP inspection

I would like to know which VLAN to enable ARP Inspection. Is it going to be on the same VLAN where the Trusted DHCP server resides on ?
Or on every VLAN in the network ?

Switch(config)#ip arp inspection vlan <VLAN Name>



I also wants to know about the DHCP Option 82 configuration.
Using IP helper-address <IP address> is enough or  we need to add:
ip dhcp relay information option

Thank you
0
Hi All,
I have a Cisco 2600 router with 2 Ethernet and 1 serial interface, I have the fa0/0 connected directly to my internet modem(Comcast) and have the interface setup as a dhcp client to the modem. I have the fa0/1 interface connected to another cisco switch.
The fa0/1 interface is assigned a 192.168.1.1/24 ip and its also acting as a dhcp server to the internal hosts..
The Comcast modem IP is 192.168.100.1 which I had to get from Comcast.
I also have an ip route 0.0.0.0 0.0.0.0 192.168.100.1
I don't have any NAT running, not sure if I really need it or not my internal LAN is working fine, I can ping the gtwy, the clients are getting ips from the dhcp server..

I'm having the hardest time connecting to the internet, not sure what I'm missing, mind you I'm very new to the world of cisco networking so just experimenting in a lab environment and help would be greatly appreciated.

thanks..
0
Hello,

We are deploying windows 7 with MDT. Everything is going good. We are using USb to deploy.
But everytime machine restars, it throws error
"     A connection to the deployment share (\\servername\DeploymentShare$)
                     could not be made.
                     DHCP Lease was not obtained for any networking device! Possible
                     Cause: Check physical connection"
when we click retry it works.
IS there any solution for this?

Thanks
0
I am running the initial configuration dialog on a Cisco 891 router.

I will be using GE 0/0 to connect to my ISP.  I want to do this through DHCP.

Enter interface name used to connect to the
management network from the above interface summary: GigabitEthernet0

Configuring interface GigabitEthernet0:
  Configure IP on this interface? [yes]:
    IP address for this interface: dhcp
% Bad Internet address.
% Enter an Internet address of the form 'X.X.X.X', where each
% letter corresponds to a decimal number between 0 and 255.

    IP address for this interface:

Open in new window

How do I specify DHCP for that interface?

Thanks!
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I have cisco 5508 lan controller and 2702i WAPs with static IP address. I want to remove static ip address and assign through cisco ios dhcp server. I'll do the following:

On cisco switch:
ip dhcp pool <pool name>
network <ip network> <netmask>
default-router <default-router IP address>
dns-server <dns server IP address>
option 43 hex <hexadecimal string>

Then go to WLC GUI and go to each AP and click "Clear all config"

On switch the ports are configured as:
switchport access vlan 111
switchport mode trunk
switchport trunk native vlan 111
switchport trunk allowed vlan 9-11, 111
spanning-tree portfast

All WAPs are in flexconnect mode.

Are these steps correct? If not, please list detailed steps. Thanks.
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Am having static IP settings for my Domain desktops. Disabling the DNS Client service is helping in name to IP resolution. Do i need DNS Client service to be running if am having static IP settings ?
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Hello -

I’m trying to free up IPs in my 1st subnet (there’s 2) and I’m down to 1 free address, according to the statistics on the scope.  Weird thing is that when I successfully moved 4 static IP printer addresses over to the other subnet, and deleted their reservations, the statistics do not increase by 4 addresses – it still shows only 1 available address.  I double-checked the active leases and do not see my 4 printer addresses leased – statically nor dynamically.  I restarted the DHCP server service thinking maybe the server just hasn’t recognized the open addresses yet – didn’t help.  Wondering why it's not releasing the addresses back into the pool.

Thanks for your help
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i want to do port forwarding to share home webserver on the internet .
i use ip nat inside source static tcp 192.168.1.5 80 interface gi0/0
but it is not working.
i don't know what to do



Building configuration...

Current configuration : 2000 bytes
!
version 12.4
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname DHCP-Server
!
boot-start-marker
boot-end-marker
!
enable secret 5 $1$K0OI$7rFPJ32VUIm4QXxC6xflE0
enable password sakhizada
!
aaa new-model
!
!
aaa group server tacacs+ sakhizada
 server 192.168.1.4
!
aaa authentication login default local
aaa authorization exec default group tacacs+ local
!
!
aaa session-id common
clock timezone Kabul 4 30
no ip routing
!
!
no ip cef
no ip dhcp use vrf connected
ip dhcp excluded-address 192.168.0.1 192.168.0.40
ip dhcp excluded-address 192.168.1.1 192.168.1.20
!
ip dhcp pool ITCKPUPool
   network 192.168.0.0 255.255.255.0
   default-router 192.168.0.1
   dns-server 192.168.0.2 192.168.0.3
   domain-name ITCKPU.EDU.AF
   lease 0 1
!
ip dhcp pool ITPool
   network 192.168.1.0 255.255.255.0
   default-router 192.168.1.1
   dns-server 192.168.0.2 192.168.0.3
   domain-name ITCKPU.EDU.AF
!
!
ip domain name ITCKPU.EDU.AF
multilink bundle-name authenticated
!
!
!
username admin privilege 15 password 0 cisco
archive
 log config
  hidekeys
!
!
!
class-map match-any UNWANTED-PCs
 match source-address mac…
0
Hello Experts,

I have been trying to compile DHCP client for ARM linux platform. I currently use Ubuntu 12.04

../includes/omapip/isclib.h:51:24: error: isc/buffer.h: No such file or directory
../includes/omapip/isclib.h:52:21: error: isc/lex.h: No such file or directory
../includes/omapip/isclib.h:53:21: error: isc/lib.h: No such file or directory
../includes/omapip/isclib.h:54:21: error: isc/app.h: No such file or directory
../includes/omapip/isclib.h:55:21: error: isc/mem.h: No such file or directory
../includes/omapip/isclib.h:56:26: error: isc/parseint.h: No such file or directory
../includes/omapip/isclib.h:57:24: error: isc/socket.h: No such file or directory
../includes/omapip/isclib.h:58:26: error: isc/sockaddr.h: No such file or directory
../includes/omapip/isclib.h:59:22: error: isc/task.h: No such file or directory
../includes/omapip/isclib.h:60:23: error: isc/timer.h: No such file or directory
../includes/omapip/isclib.h:61:22: error: isc/heap.h: No such file or directory
../includes/omapip/isclib.h:62:24: error: isc/random.h: No such file or directory
../includes/omapip/isclib.h:64:24: error: dns/client.h: No such file or directory
../includes/omapip/isclib.h:65:27: error: dns/fixedname.h: No such file or directory
../includes/omapip/isclib.h:66:27: error: dns/keyvalues.h: No such file or directory
../includes/omapip/isclib.h:67:21: error: dns/lib.h: No such file or directory
../includes/omapip/isclib.h:68:22: error: dns/name.h: No such file…
0
Hi, I've purchased 4 Sonicwall(Dell) Sonicpoint ACi units, connected to my Sonicwall NSA2600 firewall (WLAN port X4). Everything's working fine using PoE injectors (+ unmanaged switch) but I'm not able to get it working using a UniFi POE-150W PoE switch. All requirements describled here https://support.sonicwall.com/sonicwall-sonicpoint-series/kb/sw12867 are met, the switch supports 802.3at and max output pr port is 34W (min is 25 or 30 W). I'm able to connect to the WLAN (set up as virtual APs) but I'm not able to connect to internet, not getting IPs from DHCP. Any ideas how to solve this? (in my head this should be straightforward, maybe I'm wrong?)
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I have a virtual machine.  Its a file server running Server 2012.  I had a user trying to move a large amount of data earlier and something happend where the server no longer sees the network.  The server has a static address, but i can put it on DHCP and nothing changes.  I have rebooted it a few times to no avail either.  Any idea how i can get this server to talk to my network again?
0
W2012 server in branch office providing Read Only DC, DNS and DHCP. Problem is that new W10 clients are picking up IP through DHCP but not the DNS server address. Lease is showing in DHCP. Ican manually configure the DNS address in the client adapter and it works as normal, but if I select 'automatic' it doesn't pick it up.

The first PC that was configured works OK, but I haven't tried an IPCONFIG/release /renew on it as I am remote and afraid of losing it. However, the next two are both showing this problem however I can RDP to them fortunately

Nothing in the Windows event logs.

Never seen this before. Anybody else?

Thanks,
0
I am building a Domain for a SMB. They have 10 users in the office. I am putting in a HP ML110 with AD, DNS, DHCP, File/print, sql exppress, that's it. My question is how I should approach the build. Should I use Server Standard and CALs, so we can hyper v the box. Run AD on the virtual machine. Or can I use Essentials and put all the services on the one physical box. I just want the best and cost effective option.
0
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Hello.

I would like to know if there exist any command for Cisco L3 Switch that shows which VLAN is assigned to which DHCP Server (DHCP Server's IP Address for every VLAN)?

Thank you for answers.
0
I am wondering if there is a downside to this . My current DC is the primary DNS for the LAN but I am experiencing a very slow response time browsing the web .. My browsers take an abnormally long time to resolve hosts.
Running a tracert shows like 9-10 hops to get to google yahoo etc..
I am using OOL on my business and wondering if I should be using  Googles DNS as a secondary entry on my DHCP server .
Thoughts ??
0
Hi,

I need to bind some mac address on Cisco core switch DHCP server. so that every time user get the same IP.
we need to implement this policy for the white list some IP for full access


Regards,
Naresh
0
Hello - I have a printer that HAD been working ok on a specific network port in the office.  It was on VLAN 2 here, and had a static IP.  I've had to add a second subnet to increase our number of available IP addresses, and desired to move this printer into the new, 2nd subnet.  this 2nd subnet is on VLAN 6, so I changed the VLAN for the port the printer is plugged in to, and it lost connectivity.  After fighting with the static assignment and trying DHCP on the port, I brought the printer to my office where I plugged it in to a 10/100 Netgear smart-switch that is on the new, 2nd subnet (VLAN 6).  the printer accepts an IP address when plugged in to this Netgear switch.  So I left the configuration set to DHCP on the printer, and moved it back to the original LAN jack.  I confirmed the VLAN setting on the wall port is correct (VLAN 6) and also made sure the speed and duplex setting is set to AUTO.  still no dice from this wall jack.  what could be wrong??  The printer is a HP Officejet X451dn, btw.  Thanks for your help.
0
Hello,
I'm looking for the best route and/or best steps to migrate a Windows 2003 DHCP server to Windows 2012 DHCP server.
In the process of decommissioning the last remnants of Windows 2003 servers.

Thanks,
0
My Canon MF stopped working. I got a replacement from canon.

documents send to the printer/scanner will not print/scan

It's in a domain environment.

The printer got a new IP address in the DHCP I deleted the new IP and added a reservation with the IP address the the printer had before replacing it. and I see it changed on the printer screen.

Still cannot print/scan

On the workstations I see in the port configurations that it has the current IP address.

Please help
0

DHCP

9K

Solutions

4

Articles & Videos

14K

Contributors

The Dynamic Host Configuration Protocol (DHCP) is an auto configuration protocol used on IP networks and an extension of the Bootstrap Protocol. DHCP allows for computers to be configured automatically to communicate with each other over an IP network without the need for manual setup by a network administrator. The implementation of DHCP relies on a DHCP server to hand out network configuration information to DHCP-capable clients that request an IP address (and other information required or useful in communicating with other devices on an IP network). In addition to an IP address, common configuration information served over DHCP includes a default gateway, subnet mask and DNS sever(s).