DHCP / DNS on UCS vs. Router



Hi all,

I plan to setup UCS in my network. Currently the DHCP and DNS is done by my router (FritzBox). The router will be replaced by an OPNsense box shortly.

Now my question is which host shall be responsible for DNS and DHCP in the network: UCS or the router.
What are the pros and cons to host DNS and DHCP on the UCS server?

Thank you very much for your comments in advance.


Hi Jörn,

if you don’t need an actually list of the dhcp leases, use UCS for all. Then you see all configurations on one ui. Then a computer object also creates dhcp and dns objects automatically. And you can place your cname’s on the computer object, so you have all entries in one dialog.

UCS creates (if you want) an Active Directory domain. A dns server is a builtin part of a AD domain. Joined domain clients dynamically update their dns configurations.

You can share the dhcpd.leases file via apache, but there are no reserved ip`s listed. Any other hint is welcome.

Next please :wink:


Hi Jörn,

I use pfsense (migration to OPNsense is to be done some time in the near future) and relay the dhcp response to UCS servers. It works well.
For DNS I use UCS only for the local computers and external DNS, dynDNS etc. on the router.
I still want to install a proper disaster recovery management again which is also possible with PXE booting settings in UCS.
This kind of makes sense to me - everything local lans regarding is managed through UCS, everything beyond and from the outside is configured on the router.

Next please :wink:


Thanks Bernd,
how do you relay the DHCP leases to the UCS. Any link with a description?


In both pfsense and OPNsense there is a dedicated menu under Service - DHCP called ‘relay’ or in pfsense-german ‘DHCP Weiterleitung’.
You just have to select interfaces / Schnittstellen where clients will be demanding leases and fill in the field with the IP of the UCS DHCP server(s).