25.7 is looking good! Out of curiosity, when upgrading an existing 25.1.11 instance. I see there is no option to automatically convert to Kea DHCP - what is the best way top migrate to Kea ? Or on the flip side, how can we still use the ISC DHCP moving forward ??
Thx in advance and Happy Monday on top!
Hello, there is no option for an automatic migration to either KEA or Dnsmasq DHCP.
What is offered are CSV import and export of reservations in ISC, KEA and Dnsmasq.
You can still use ISC going forward, it will be an optional plugin in the future.
This page should give you a nice overview of the possible options: https://docs.opnsense.org/manual/dhcp.html
I suggest if you do not have a very large network with thousands of clients, or HA, to go with dnsmasq if you want to change.
Understood - I have a small network with like 100 clients divided into 4 VLANs - so I guess I will look into Dnsmasq - no rush to change . . .
Thanks for your prompt reply!
No problem.
Check out this configuration example and you will most likely have very minor to no issues migrating.
https://docs.opnsense.org/manual/dnsmasq.html#dhcpv4-with-dns-registration
Only thing to keep in mind, both ISC and Dnsmasq try to bind to port 67/68, so after configuration you must disable all ISC DHCP ranges to disable it completely so dnsmasq can bind to the DHCP ports.
Wow - on the surface, dnsmasq seems complex - like setting DHCP reservations, changing default GW or DNS conflict with Unbound is not so intuitive like the ISC DHCP
Always keen to learn something new - but these are many confusing options available ?!?
A simple guide or how-to convert from ISC to dnsmasq (also considering unbound) might be helpful - or if you can point me in the right direction?
Thx
I migrated from ISC and Unbound last night to DnsMasq full.
I no longer have ISC or Unbound and it's all running great.
I didn't find it particularly difficult, but I did use ChatGPT to create a CSV for DnsMasq import from my ISC reservations....
This is on 25.1.11, doing it in prep for 25.7....
The guide how to configure Dnsmasq is linked above. Do you have any specific questions after reading it?
In essence you configure Dnsmasq like in that example, keep it disabled until you finish.
Then afterwards disable all ISC DHCP ranges, and afterwards enable Dnsmasq.
In 25.7 you will not need any reservation Chatgpt tricks, there will be a native export for them.
https://github.com/opnsense/core/pull/8929
Got it - Thx - will try in a test environment before I muck up my production environment . . .
Out of curiosity, what are the defaults in a "fresh" install of OPNSense 25.7 ?? Is unbound and dnsmasq automagically used ??
While it is a suitable use case, thousands of clients are not pre-requisite for using Kea. In 25.1 I switched from ISC to Kea very easily. It is a good solution even with a few sub-nets and perhaps twenty clients. You have options.
When it comes to DHCP, a larger number of users apparently fear "options". :)
Cheers,
Franco
But why is it that KEA is not recommended for small installations. What's wrong with KEA for SOHO?
You can use Kea for anything as much as Dnsmasq, but the ease of use for general purposes with Dnsmasq is superior IMO.
Disclaimer: I'm still using ISC in my setups.
Cheers,
Franco
Quote from: Monviech (Cedrik) on July 21, 2025, 11:07:22 AMHello, there is no option for an automatic migration to either KEA or Dnsmasq DHCP.
What is offered are CSV import and export of reservations in ISC, KEA and Dnsmasq.
You can still use ISC going forward, it will be an optional plugin in the future.
This page should give you a nice overview of the possible options: https://docs.opnsense.org/manual/dhcp.html
I suggest if you do not have a very large network with thousands of clients, or HA, to go with dnsmasq if you want to change.
Hi,
Button import for IPv6 is missing. Fine for IPv4.
Fred
> Button import for IPv6 is missing. Fine for IPv4.
This is intended, because the DHCPv6 transition is a working item for 26.1 now. 25.7's scope is DHCPv4 default changes.
Cheers,
Franco