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11

The machine's MAC address changing won't affect anything. Active Directory isn't concerned with the link layer. Yep you can just plug it back in, and the DC will catch up. (Now on the other hand, if the DC's hard drive was encrypted with something like Bitlocker, replacing the motherboard (and thus the onboard TPM chip) would mean the end of the road for ...


4

RFC 3118 allows for authentication in DHCP messages although AFAIK it isn't implemented in the current DHCP servers. If you want to secure your network a better approach is IEEE_802.1X where clients must authenticate themselves to the switch port before they can access the network. That means that even if an unauthenticated system is configured with a ...


3

The iLO RAC is a completely separate NIC. If you want the OS to have a network connection you must also connect the on-board NIC to the network. I'm guessing you don't have the NIC plugged in, and Ubuntu has no magical powers to make a network connection out of an unplugged NIC.


3

You gave an IP address inside the subnet instead of the address of the subnet itself. Replace subnet 10.0.2.1 with subnet 10.0.2.0, and it should work.


2

on the mac that is hosting the rogue DHCP service. sudo launchctl unload -w /System/Library/LaunchDaemons/bootps.plist This will turn off bootpd, which is the DHCP server. You might also check the internet sharing settings in system preferences (which is the other common user of DHCP on the system besides Mac OS X Server) To see if Mac OS X Server is ...


2

If your DHCP server hasn't assigned an IP address, it has no knowledge that the IP address is in use. This is mitigated by setting up a DHCP "Reservation" - and that's what you need to do. Go into the DHCP server and assign a reservation for that IP address, so that the server doesn't try to assign that IP address to another device. You didn't tell us what ...


2

Yes you can do that. Just keep your DHCP range deactivated. The DHCP server doesn't distribute ip addresses then. Also, it might be worth trying to google for a config file migration. A long time ago I also migrated a DHCP server from Win 2003 to Win 2008 and I remember that there are command line tools to export the config and static leases to a text like ...


2

In my case, the answer was LLDP. By enabling LLDP on my Cisco switches, the phones were able to learn of the Voice VLAN before they started the DHCP process.


2

A great way of doing this is with 802.1x and port-based authentication, combined with a captive portal. You set up a captive portal on your gateway to make the user accept terms/conditions or enter a guest password. You assign that captive portal onto your guest VLAN. Then you use 802.1x on all your switch ports. If the MAC address authentication passes, ...


1

No, this will not work. Both DHCP Servers must be at least Windows Server 2012. As an aside, you should be removing 2003 from your environment quickly, not tying it in to new infrastructure. It goes end of extended support early next year.


1

There is no "prioritization" per se. What will happen is that the two will intend to answer for the same ARP lookups and will behave unpredictably. Sometimes one will work for a while and then stop. Some times the other may work for a while. Or neither will work. Things might appear to work for a while and then mysteriously stop. Some other ...


1

The DC itself is not a problem. The DHCP takes some careful handling to prevent connectivity issues for your users: Best approach (done this myself several times): Bring the DC up without LAN. Log on locally and go in the DHCP settings. If it is currently NOT enabled then enable "collision detect". Then stop the DHCP service. Reconnect the DC to the ...


1

Well, which DHCP Client do you use? There are some different around. Considerung you are using the standard one from the ISC, you need to put a like like this in your dhclient.conf: reject 10.0.0.5; Where you replace the IP of course with the IP of the server whose offers you don't want. That's it. For futher information take a look at the man page of ...


1

The proper way to do what you are asking would be use to Policy filtering at the scope level. You can change what PXE Boot options if your DHCP is serving and several other DHCP options as well as IP range and denying service.


1

This problem can be solved via a dhclient hook script under /etc/dhcp/ in my case I named the file dhclient-eth1-up-hooks which is executed when eth1 is switched up. Inside the script I have a simple ifconfig eth1:0 inet xxx.xxx.xxx.xxx netmask 255.255.255.248



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