DHCP

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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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Ive a new netgear jgs524PE switch and a netgear orbi rbk50 I would like help to setup correctly.

Currently the isp router is giving a gateway on 192.168.0.1 one port of that runs to the Netgear orbi, The orbi in turn has created its own network on 192.168.1.1, my switch is connected to the orbi with an ip 192.168.1.66.

I have nas connected to the switch, previously it was on 192.168.0.185 but I guess that now needs to be changed?

What is the best way to set up here? The Orbi provides netgear circle which allows me to control the kids devices with devices on the orbi network. So I think the switch has to stay as currently connected.

I am not sure if I should have the Router providing dhcp.

Your advice would be welcome.

This is a home setup but I do require 1gb cable speeds as I zoom a lot. The  synology nas server needs to be accessible from outside.
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Hello,

My company currently it's moving to a new phone system and we are stock. our DHCP it's set to IP Scope 192.168.16.xx and I created a second Scope 10.11.0.xx so it can connect via VPN tunnel with the VoIP system of our another office (we are in So. Cal and the other office in Florida) now, To my knowledge I need to create the scopes and the services on DHCP so I can setup the relay to ensure that traffic can go from the 10.11 network using the 192.168 network as gateway and at some point  create a VLAN in my switches to route.

I did all the first part until before the VLAN part, I have some problems.

1-Computers on my Scope 192.168.16.xx are registering on the 10.11.0.xx I need to know how to stop them from doing that, I need to keep them alive but without merging

2-Do I need to create a vlan to route all my VoIP traffic ? we have layer 2 switches and the router it's managed by our ISP or Do I need to setup a a new port in my firewall with that subnet routing all traffic from 10.11 to the public IP

I have a VM running server 2008 R2 as my DHCP I have 2 virtual NICS installed one running on 192.168.16.xx and the other on 10.11.0.xx
I have RRA installed with IGMP installed, and my gut tells me that I did something wrong

I have not done something like this in years so if there is anyone that can give me some guiadence I will really appreciate it.
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I have a server that has an IP address that was static but somehow changed after reboot was done on it.  The address was reserved on another DHCP server to prevent it from being used.  I am finding when I change the IP back to the static address it had, I get an IP conflict error showing up. I pinged the IP address on the LAN and I confirmed it is not being used by another device.  I was thinking DHCP is probably preventing me from using that address at this point so I tried disabling DHCP temporarily so I could then change that server IP back to it's static but I am still getting the conflict error.  

Any ideas what is causing this?
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I have two 3750 switches that are connected and working but here is my only issues. By the way I am very new to networking so please excuse me being naïve .

My issue is when I have a machine on a different subnet other than the main one 10.46.72.x DNS does not resolve even though I manually add and with a DHCP scope that I removed will not work. Can someone please tell me what  am doing wrong. Here is a copy of the config

[code][/

User Access Verification

Password:
Base-sw1>show running
Base-sw1>en
Base-sw1>enable
Password:
Base-sw1#sh ru
Base-sw1#sh running-config
Building configuration...

Current configuration : 3753 bytes
!
version 12.2
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Base-sw1
!
enable secret 5 $1$lwLf$CJoNDGBl4Ck6AAm/woBVM0
enable password secret cisco
!
no aaa new-model
switch 6 provision ws-c3750g-24ts
system mtu routing 1500
ip subnet-zero
ip routing
!
!
!
!
no file verify auto
spanning-tree mode pvst
spanning-tree extend system-id
!
vlan internal allocation policy ascending
!
interface GigabitEthernet6/0/1
 switchport trunk encapsulation dot1q
 switchport mode trunk
!
interface GigabitEthernet6/0/2
 switchport trunk encapsulation dot1q
 switchport mode trunk
!
interface GigabitEthernet6/0/3
 switchport trunk encapsulation dot1q
 switchport mode trunk
!
interface GigabitEthernet6/0/4
 switchport trunk encapsulation dot1q…
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Hello,

I am trying to configure DHCP options for HP Thin Clients to boot into PXE. I am working off this documentation from HP

http://h10032.www1.hp.com/ctg/Manual/c04333240

I understand about PXE, and what I don't really understand why HP says 43 and 60 should be removed

And want to do is have these options set in powershell script because we have several different subnets
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I had this question after viewing Cisco ASA 5505 host license limit workaround and dhcp lease time.

In my office network some end users cant access the internet even though they are connected to the lan.

Is there a workaround ? I am using Cisco asa 5505 with 50 license limit.
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I use different netsh commands to run individual back ups of DHCP servers.
For example:
netsh dhcp server dump > \\10.0.0.1\dhcp$\Area1\dhcpcfg.txt
netsh dhcp server export \\10.0.0.1\dhcp$\Area1dhcpdb all
pause
netsh dhcp server dump > \\10.0.0.2\dhcp$\Area1\dhcpcfg.txt
netsh dhcp server export \\10.0.0.2\dhcp$\Area2\dhcpdb all
pause
I have to go on each server to run this
Please indicate a power shell command I could use to run once and back up all my dhcp servers
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Windows Server 2012 R2 DHCP - Left hand Reservation list is not in numerical order

Hi, I have two DHCP servers at one physical site (Failover setup) that don't show the DHCP reservation order in numerical sequence, all my other DHCP servers at other sites however do show them in numerical order.
We reserve our IP addresses against MAC addresses, so it can be annoying trying to find the IP reservation in the left hand list.
The right hand column can be easily sorted in numerical order but that doesn't help, as all properties are set in the left hand column.
Any ideas on how to correct this ?
Regards
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Have a small environment with no networking engineers. About 30 laptops on and off the wired and wireless throughout the day. It makes it difficult for deploying applications and scripts to them (like with PSexec or PDQ). Both DHCP and DNS are on 2 windows servers replicated.
Is there a recommended approach to updating a laptops IP when it goes from wired to wireless faster?
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I have a VLAN network that is out of IP addresses. We have to stay on IPv4 for a number of reasons, so I think the best way to fix the issue is to add a subnet range. The current subnet is 192.168.4.0 and I would add a subnet 192.168.5.0, then move all of the statically assigned devices to that network.... which should avoid the complexities of setting up DHCP and IP helpers on the switches. There are some other subnets and VLAN's configured as well, and the switches are stacked. The switches are Aruba L3 switches. Here are the VLAN setups- Subnets's 3rd octets match the VLAN ID for the 192.x.x.x networks:
VLAN ID         Name              IP
1                       DEFAULT        192.168.4.253
         Tagged:  1/37,1/43-1/44,2/45-2/48,3/4,3/6
         Untagged: 1/1-1/10,1/12-1/17,1/19,1/21-1/34,1/36,1/38-1/42,1/45-1/48,1/A1-1/A2,2/1-2/44,3/1-3/3,3/5,3/7-3/24
2                       VoIP                 172.16.x.xx
         Tagged: 1/1-1/48,1/A1-1/A2,2/1-2/48,3/1-3/3,3/7-3/24
         Untagged: 3/4,3/6
5                       Facility2           192.168.5.254
         Tagged: 1/17
         Untagged: 1/11,1/18,1/20,1/37
7                       Facility3           192.168.7.254
          Tagged: 1/45
          Untagged: 1/35
8                       Facility4           192.168.8.254
          Tagged: 1/46
          Untagged: 1/43


So, I am not touching the VoIP network.
The 5 VLAN is the one I have set up, but I am unclear on the whole tagging versus …
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Need some help in tracking down an IP conflict that I have.  DHCP servers are Windows 2016 servers (setup in a failover scenario) but I have a MacBook that has had this happen twice in the last month.  He will get a popup saying:

Another device on the network is using your computer's IP address (10.3.110.204).  

I'm not sure if this IP was for his wired connection or his wireless but only seems to affect his MacBook.  With DHCP servers there shouldn't really ever be IP conflicts (unless someone adds a static IP which I don't think this is the case here - it could be but I doubt it).  In DHCP servers, logs don't show anything...

Anyway at this point to track down what grabbed the .204 IP?
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I am planing to install DHCP fail-over in our Windows 2012 R2 environment. The current DHCP is on a DC.

There are so many article over the internet. Experts out there must have implemented DHCP fail-over. Have you had any problem with it?
I would appreciate if you could advice me  the best practice etc.
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I have a 2012 r2 DHCP server . we are currently only using static reservations .   Why do we need a lease time if the static reservation is permineat?
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When deploying an image over PXE I'm getting errors PXE-T04 and PXE-P36.  I have tried to start from scratch on the imaging server with no luck.  I'm have installed DHCP and WDS on the imaging server.
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I have a Ubiquiti USG device here.

Its a quite simple setup.

-  Its WAN1 port is connected to my modem-router.
-  its LAN 1 port is connected to an Ubquiti Edge Switch

I can get internet perfectly if i plug cable from modem into switch. However, when internet goes thru the USG device to Switch - I get no internet.

It is as if the USG is blocking internet to the switch.

The USG is acting as DHCP server. What could be blocking the internet in the USG? Any suggestions would be much appreciated.
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My company will be moving in a few weeks and as part of the move, I'll be phasing out two old domain controllers. Before I do that, I plan to move DHCP services to the new DCs. I tried to set this up while at our current location, but then realized that the IP Helper on our switch points to the old domain and this was (likely) preventing our new one from responding to and distributing addresses.

So my question is - if I just set up the new office with the IP helper for my VLANs on new switch hardware pointing to the new DC/DHCP server, am I likely to run into issues? (The old DCs would still be available but I'd hope not responding to DHCP/ DNS requests.)

Or, should I really look to tweak the switch settings in the current location to include the new DHCP server before I move?

Thanks.
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Question from a Quallys report QID is 119518
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Experts - have what should be a fairly simple setup, comprising an HP 1920S switch - a Ubiquiti Access Point - and a TZ-400 Sonicwall. Trying to get public/guest WiFi running on VLAN-100, but users not pulling an IP address. Works fine on the Private WiFi network, running on default VLAN-1.

I have this near same setup working at other locations I've done so far - with the only difference between this non-working site and the working sites, is the switch in this non-working site is an HP 1920S switch - whereas other sites have rebranded Aruba switches installed that support CLI.

I've worked with Sonicwall support earlier today and they're not seeing the guest wifi DHCP request hitting the Sonicwall X0:100 interface when a user attempts to connect to the public wifi. They've confirmed the configuration is correct on the Sonicwall.  SHould be OK as it's basically a mirror configuration from other sites that are working.

So this is what I have so far:

**DHCP**   Managed by Sonicwall

DHCP assignment for private internal/wifi office 10.10.x.x and is working,
DHCP assignment for public WiFi is 172.16.1.x and is not working.


** VLAN Info **

Private WiFi and internal office traffic all running on default VLAN-1
Public WiFi is configured to run on VLAN-100.

** Switch Info **

Port #1 is the Sonicwall
Port #2 is the Ubiquity Access Point

Sonicwall support thinks it's an issue upstream, most likely the 1920S switch.  The 1920S only allows GUI. …
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Dear Experts,

i am using ESXi 6.5 with VCSA, I have multiple vlan environment and my dhcp server is a windows  vm. my problem is that broadcast from other vlan does not reach to dhcp server.

so i am thinking that if i make port of the vm as trunk so that it can receive requests from other vlans as well.

Please advise how can i do that, or if someone has some other way to do it.
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I have a small business that wants to move entire server to cloud.

I am new to this and wanted to know what are the steps to setup an offsite server?
I may not be using the correct terminology so bear with me.

I have a customer who has 10 windows 7 pro and 5 windows 10 pro machines 3 Network Printers. They use Quickbooks and have their files on the server. This is a single server that does DHCP, DNS, File and Print Services.

I want to setup on Azure a 2012 or 2016 VM where i can make it a DC and setup the shares and move all the customers files and applications on the Azure VM. I want to eliminate their onsite server.
I would setup their firewall as the DHCP Server.

I understand that the internet connection plays a big part but lets assume they have a High Speed Fiber Connection say 100M

Can this be done and what are the cons to doing this.
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I am going to be Migrating a SBS2003 server to a Server 2012 standard R2 server.

I have been looking online for step by step directions to get this done.
They had another IT company that setup the 2012 server in VMware.
They already replicated active directory and DHCP and DNS on the 2012 server.
The SBS2003 server is on a physical Machine so what we intend on doing is back up the SBS server into a VHD or VHDK using disk2vhd. and attaching it to VMware as a guest. so if anything goes wrong we can just put the physical server back online.

We will also be setting up StorageCraft backup before starting the migration so if I need to restore the 2012 server in case something goes wrong and we have to start over.
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Bandwidth allocation - we are trying to increase our dburg bandwidth, currently its at 25%, we have class-default at 17%. Can we drop class default to 10% and increase dburg to 33%. Will it cause performance issues on our router? to better help we have a 500MB pipe

below is the router config




ip dhcp pool ccp-pool
 import all
 network 10.10.10.0 255.255.255.248
 default-router 10.10.10.1
!
!
ip domain name domain.com
ip name-server 8.8.8.8
ip cef
no ipv6 cef
multilink bundle-name authenticate
!
class-map match-any domain
 match access-group name VPN-TO-NY
class-map match-any VoIP
 match access-group name VoIP-NY
class-map match-any Broadcast-Video
 match ip dscp cs5
class-map match-any Outbound-Priority
 match access-group name VoIP-Bos
 match access-group name Polycom-Bos
 match access-group name TO-SFB
class-map match-any Bulk-Data
 match ip dscp af11  af12
class-map match-any Multimedia-Steaming
 match ip dscp af31
class-map match-any Interactive-Video
 match ip dscp cs4
 match access-group name Lync-out
class-map match-any Net-Control
 match ip dscp cs6
class-map match-any Multimedia-Conferencing
 match ip dscp af41
class-map match-any OAM
 match ip dscp cs2
class-map match-any Inbound-Priority
 match access-group name VoIP-NY
 match access-group name Polycom-NY
 match access-group name From-SFB
class-map match-any Transactional-Data
 match ip dscp af21
class-map match-any Voice
 match ip dscp ef
class-map …
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Hey Folks, were trying to move DHCP off of our Firewall right now over to our Server that is running DHCP. I take it that as long as we have identical scopes including the reserverations and changing lease times for our machines to get new DHCP leases, we shouldn't see any issues arise. Is there anything else to take into consideration before proceeding?
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I have one DC  with DHCP and DNS all in one. I am trying to connect a phone but it does not get an IP from the DHCP, Rebooted the server still getting (The DHCP service failed to see a directory server for authorization) error.

The phone (Cisco IP phone SPA 504G)  just sits on utilization network.
All other devices get IP and the lease time is set to 1 day.  It is when I try and add a new phone.
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cannot ping my cisco switch - its a Cisco SG350X layer 3 switch - please help

here is the running config

snmp-server location "8th Room"
snmp-server contact
ip name-server  192.168.11.6
ip telnet server
!
interface vlan 1
 no ip address dhcp
!
interface vlan 3
 name "Corp"
!
interface vlan 5
 name "Guest"
!
interface GigabitEthernet1/0/1
 switchport access vlan 5
!
interface GigabitEthernet1/0/2
 switchport access vlan 5
!
interface GigabitEthernet1/0/3
 switchport access vlan 5
!
interface GigabitEthernet1/0/4
 switchport access vlan 5
!
interface GigabitEthernet1/0/5
 switchport access vlan 5
!
interface GigabitEthernet1/0/6
 switchport access vlan 5
!
interface GigabitEthernet1/0/25
 switchport access vlan 5
!
interface GigabitEthernet1/0/26
 switchport access vlan 5
!
interface GigabitEthernet1/0/27
 switchport access vlan 5
!
interface GigabitEthernet1/0/28
 switchport access vlan 5
!
interface GigabitEthernet1/0/29
 switchport access vlan 5
!
interface GigabitEthernet1/0/30
 switchport access vlan 5
!
interface GigabitEthernet1/0/48
 dot1x reauthentication
 ip address 192.168.11.27 255.255.254.0
 no switchport
!
interface TengigabitEthernet1/0/1
 description UPLINK
 no spanning-tree portfast
 no switchport
 switchport mode trunk
 switchport trunk native vlan none
!
interface TengigabitEthernet1/0/2
 switchport access vlan none
!
interface TengigabitEthernet1/0/3
 switchport access vlan none
!
0

DHCP

10K

Solutions

15K

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).