I guess the DHCP or DNS server shouldn't influence the performance of the CCM. You can easily configure DHCP and DNS server for 2000 phones and 4000 device-profiles. This shouldnt create any problems as such. There is no limitation on the CCM side, if the DHCP server has a pool of IP addresses, which can suffice all the devices, then there should be no problem at all for the CCM. Hope this answers your question.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.