KEA DHCP - lacking features

jimp

If you need custom options, keep using ISC for now.

pfsvrb

@jimp said in KEA DHCP - lacking features:

If you need custom options, keep using ISC for now.

@jimp do you know if the Unbound restarts with registered dynamic clients will be fixed one KEA integration is finalized? I don't use custom options with ISC DHCP however, I do use the static leases function to get around the constant Unbound restarts (and loss of Unbound caching) that happen when I attempt to use the "register DHCP leases in DNS resolver" option. I've been following Bug 5413 for years but unfortunately it just keeps getting pushed perpetually. Is there any possibility KEA fixes this when its finalized?

Bug for reference: https://redmine.pfsense.org/issues/5413

Gertjan

@pfsvrb said in KEA DHCP - lacking features:

do you know if the Unbound restarts with registered dynamic clients will be fixed one KEA integration is finalized?

Registering DHCP lease clients, this one :

?

KEA has been introduced so it resolves just that issue, like redmine.pfsense.org/issues/5413
Looks like KEA will replace DHCPd by ISC anyway.

edit : a bit like : at first, pfSense (M0n0wall) came with dnsmasq, a DNS forwarder.
Then unbound, a resolver was introduced as a option, as a pfSense package (if I recall well), and then it as build in, as it is today : you have a choice : just one, or the other, or, if you like, both of them. Unbound is now the default.

pfsvrb

@Gertjan
Thanks for the response but this was more concerning the persistent Unbound restarts under the current implementation, and the need to keep ISC DHCP for reserved DHCP IPs in order to bypass the restart issue. See the underlined in the screenshot showing that KEA doesn't currently support registered or dynamic DHCP clients (my use case would be both of those).

b810411f-1548-4bde-916c-2777fa985408-Screenshot from 2023-11-24 01-52-06.png

Gertjan

@pfsvrb

At first, I was really convinced that the static dhcp mac leases were also use by KEA, but I was mistaken.
In some other thread, jimp corrected me on that.
So I borrowed some pfSense sub-GUI scripts to re create my own /var/unbound/host_entries.conf file before KEA gets started, as I still want to test drive KEA,- and have my local 'DHCP' devices resolved by host name.

The dynamic DHCPd clients : I'll leave that one to Netgate ;)

pfsvrb

@Gertjan So it will resolve the static DHCP entries even though the release notes do not indicate that? Or are you saying that you have it working only after some manual script to convert static entries to Unbound?

If you have to manually script something in to Unbound I'm not sure how this is relevant to the discussion? It would definitely fall under the "lacking features" of the thread though. ;)

Gertjan

@pfsvrb said in KEA DHCP - lacking features:

It would definitely fall under the "lacking features" of the thread though. ;)

Exact.

Open your /var/unbound/unbound.conf file, this is the main unbound config file.;
When you use 'dhcpd', you'll find :

# Static host entries
include: /var/unbound/host_entries.conf

This entry will exist when you've checked :

This /var/unbound/host_entries.conf looks lie :

local-zone: "bhf.tld." static
local-data-ptr: "127.0.0.1 localhost.bhf.tld"
local-data: "localhost. A 127.0.0.1"
local-data: "localhost.bhf.tld. A 127.0.0.1"
local-data-ptr: "::1 localhost.bhf.tld"
local-data: "localhost. AAAA ::1"
local-data: "localhost.bhf.tld. AAAA ::1"
local-data-ptr: "192.168.1.1 pfSense.bhf.tld"
local-data: "pfSense.bhf.tld. A 192.168.1.1"
local-data-ptr: "2a01:cb19:907:a6eb:92ec:77ff:fe29:392c pfSense.bhf.tld"
local-data: "pfSense.bhf.tld. AAAA 2a01:cb19:907:a6eb:92ec:77ff:fe29:392c"
local-data-ptr: "192.168.1.2 bureau2.bhf.tld"
local-data: "bureau2.bhf.tld. A 192.168.1.2"
etc.
......

When you switch to kea, these (both) : are not present anymore on the unbound main config setup page :

The very net time you 'save' the unbound config main settings page, and then Apply (== restart) unbound, the /var/unbound/host_entries.conf will still include the host overrides, but not the DHCP static MAC lease info anymore.

jimp

@pfsvrb said in KEA DHCP - lacking features:

@jimp said in KEA DHCP - lacking features:

If you need custom options, keep using ISC for now.

@jimp do you know if the Unbound restarts with registered dynamic clients will be fixed one KEA integration is finalized? I don't use custom options with ISC DHCP however, I do use the static leases function to get around the constant Unbound restarts (and loss of Unbound caching) that happen when I attempt to use the "register DHCP leases in DNS resolver" option. I've been following Bug 5413 for years but unfortunately it just keeps getting pushed perpetually. Is there any possibility KEA fixes this when its finalized?

Bug for reference: https://redmine.pfsense.org/issues/5413

That's the goal. We're designing a completely new mechanism for Kea to talk to Unbound using its API and/or unbound-control functions to add/remove/update DNS information dynamically without restarting the daemon.

jimp

@pfsvrb said in KEA DHCP - lacking features:

@Gertjan So it will resolve the static DHCP entries even though the release notes do not indicate that? Or are you saying that you have it working only after some manual script to convert static entries to Unbound?

If you have to manually script something in to Unbound I'm not sure how this is relevant to the discussion? It would definitely fall under the "lacking features" of the thread though. ;)

It's technically not supported but if you happened to have DNS registration of static mappings enabled before switching to Kea, then Unbound will still parse the static mappings and use them for DNS resolution. But it only updates when Unbound is restarted, not when mappings are edited.

So while it may function (partially) it's not officially supported yet.

Robert_Knabe

@maverickws said in KEA DHCP - lacking features:

Hiya,

I have taken a look into the new DHCP Server service, KEA, only to find out that when enabled, the Additional BOOTP/DHCP Options disappear.

Now, Additional BOOTP/DHCP Options is a real thing that provides said DHCP config options to the client.
I have dozens of machines that require this option, and by setting the MTU on the correspondent interface, that doesn't make the clients set the proper MTU.
That's DHCP option 26.

This is a critical component and honestly if pfSense is dropping this, I will have to find another firewall software that supports it. Even if I finally have to go Cisco, I mean, I'm completely baffled by this.

Another custom option that is indispensable to me is option 121, the configuration of routes on the client. Without that a centralized client management is not possible. For now i will keep ISC DHCP.

molykule

Hi,
I have 2 different subnets LAN and OPT1. I have a laptop, which has static IP address defined in both subnets, for lan the ip is 192.168.2.20, and for opt1, the ip is 192.168.3.20.
When I start kea dhcp, the dhcpd service would not start, I get error below

ERROR [kea-dhcp4.dhcp4.0x115d56a12000] DHCP4_INIT_FAIL failed to initialize Kea server: configuration error using file '/usr/local/etc/kea/kea-dhcp4.conf': Can't add class: Client Class: mac_000E9******* has already been defined (/usr/local/etc/kea/kea-dhcp4.conf:103:13)

ERROR [kea-dhcp4.dhcp4.0x115d56a12000] DHCP4_CONFIG_LOAD_FAIL configuration error using file: /usr/local/etc/kea/kea-dhcp4.conf, reason: Can't add class: Client Class: mac_000E9******* has already been defined (/usr/local/etc/kea/kea-dhcp4.conf:103:13)

ERROR [kea-dhcp4.dhcp4.0x115d56a12000] DHCP4_PARSER_FAIL failed to create or run parser for configuration element client-classes: Can't add class: Client Class: mac_000E9******* has already been defined (/usr/local/etc/kea/kea-dhcp4.conf:103:13)

I have removed the client identifier in both subnets. Is there any work around for such scenario or I am missing something,
I have posted it in separate in topic before, hoping if somebody else ran in the same issue, but haven't heard anything
thanks,

Gertjan

@molykule said in KEA DHCP - lacking features:

I have 2 different subnets LAN and OPT1. I have a laptop, which has static IP address defined in both subnets, for lan the ip is 192.168.2.20, and for opt1, the ip is 192.168.3.20.

First : I presume that you mean : a static MAC DHCP Lease, and not a static IP address setup, as (for me) such a setup doesn't use DHCP at all.

I do have the same scenario :
On LAN, my Phone has been set up with it's (non random !) MAC :

and on my PORTAL (another LAN or OPTx) interface :

Works fine for me

My phone gets 192.168.2.6 on the portal network, and 192.168.1.35 on the LAN network.

I'm using a non identical "Client ID" and "Hostname" on these two networks, could that be the reason ?

I've checked the kea config file : /usr/local/etc/kea/kea-dhcp4.conf - looks fine to me.

molykule

@Gertjan Thank you for replying. You are correct for static MAC DHCP lease.
however I still got the same error. I do notice that you dont have static ARP checked. I dont know if that could be the cause,
please let me know,
Thanks again for help,
Screenshot 2023-11-30 165922.png
Screenshot 2023-11-30 165553.png

Screenshot 2023-11-30 165555.png

In the file /usr/local/etc/kea/kea-dhcp4.conf, this occurs 3 times because its defined in 3 different subnets, which is erroring out.
{
"name": "mac_8C705AB898C4",
"test": "substring(hexstring(pkt4.mac, ''), 0, 12) == '8c705ab898c4'"
},

Log:
Nov 30 16:53:36 kea-dhcp4 36871 ERROR [kea-dhcp4.dhcp4.0x253335c12000] DHCP4_INIT_FAIL failed to initialize Kea server: configuration error using file '/usr/local/etc/kea/kea-dhcp4.conf': Can't add class: Client Class: mac_8C705AB898C4 has already been defined (/usr/local/etc/kea/kea-dhcp4.conf:164:13)
Nov 30 16:53:36 kea-dhcp4 36871 ERROR [kea-dhcp4.dhcp4.0x253335c12000] DHCP4_CONFIG_LOAD_FAIL configuration error using file: /usr/local/etc/kea/kea-dhcp4.conf, reason: Can't add class: Client Class: mac_8C705AB898C4 has already been defined (/usr/local/etc/kea/kea-dhcp4.conf:164:13)
Nov 30 16:53:36 kea-dhcp4 36871 ERROR [kea-dhcp4.dhcp4.0x253335c12000] DHCP4_PARSER_FAIL failed to create or run parser for configuration element client-classes: Can't add class: Client Class: mac_8C705AB898C4 has already been defined (/usr/local/etc/kea/kea-dhcp4.conf:164:13)
Nov 30 16:53:36 kea-dhcp4 36871 INFO [kea-dhcp4.hooks.0x253335c12000] HOOKS_LIBRARY_CLOSED hooks library /usr/local/lib/kea/hooks/libdhcp_lease_cmds.so successfully closed
Nov 30 16:53:36 kea-dhcp4 36871 INFO [kea-dhcp4.dhcpsrv.0x253335c12000] DHCPSRV_CFGMGR_SOCKET_TYPE_DEFAULT "dhcp-socket-type" not specified , using default socket type raw
Nov 30 16:53:36 kea-dhcp4 36871 INFO [kea-dhcp4.dhcpsrv.0x253335c12000] DHCPSRV_CFGMGR_ADD_IFACE listening on interface igb3
Nov 30 16:53:36 kea-dhcp4 36871 INFO [kea-dhcp4.dhcpsrv.0x253335c12000] DHCPSRV_CFGMGR_ADD_IFACE listening on interface igb2
Nov 30 16:53:36 kea-dhcp4 36871 INFO [kea-dhcp4.dhcpsrv.0x253335c12000] DHCPSRV_CFGMGR_ADD_IFACE listening on interface igb1
Nov 30 16:53:36 kea-dhcp4 36871 INFO [kea-dhcp4.dhcpsrv.0x253335c12000] DHCPSRV_CFGMGR_ADD_IFACE listening on interface igb0

johnpoz

@molykule said in KEA DHCP - lacking features:

I do notice that you dont have static ARP checked.

Yeah that for sure could be problematic - and currently static arp doesn't even work correctly using isc dhcpd.. Sure it sets them, but when your client does dhcp for it.. It switches from perm to dynamic in the arp table..

There is a thread and redmine about it.

https://forum.netgate.com/topic/184155/static-arp-in-dhcp-overwritten

I really wouldn't count on kea not being weird if your doing anything other than just serving IPs out of a pool..

molykule

@johnpoz
Thank you for the detailed reply and the links,

Gertjan

@johnpoz said in KEA DHCP - lacking features:

I really wouldn't count on kea not being weird if your doing anything other than just serving IPs out of a pool..

So can I deduct that I have a run of the mill networks so kea works fine for me ? ;)

JonathanLee

@Gertjan any network with a firewall is far from run of the mill ️ especially one running a new cutting edge kea dhcp server. Give yourself credit where credit is due.

omiwaaa

Is there a way to get back to ISC DHCP if I clicked to migrate to KEA? If not, then I will check if any OPTION can be set directly into files, I need it for WAPD.

SteveITS

@omiwaaa said in KEA DHCP - lacking features:

Is there a way to get back to ISC DHCP if I clicked to migrate to KEA?

On that same page you can change back.

omiwaaa

@SteveITS unfortunately I dismissed the banner and no other possible option found in the section. I'll workaround deploying another DHCP on another server while the module gets populated with more fields.