Opened 3 years ago

Last modified 3 years ago

#5048 new defect

Kea servers should be able to use a subnet's domain-name as a qualifying suffix for DDNS

Reported by: tmark Owned by:
Priority: medium Milestone: Outstanding Tasks
Component: ddns Version: git
Keywords: Cc:
CVSS Scoring: Parent Tickets:
Sensitive: no Defect Severity: N/A
Sub-Project: DHCP Feature Depending on Ticket:
Estimated Difficulty: 16 Add Hours to Ticket: 0
Total Hours: 0 Internal?: no

Description

It would be very useful for Kea server's to be able to use subnet options such as the domain-name option as the qualifying suffix for DNS requests rather one a single global value.

From Kea's user request:

"Am doing my first deployment of KEA after using ISC-DHCP for..ever.

Am trying to replicate an existing configuration with multiple subnets updating different forward DNS domains and am unclear on how to accomplish this as all examples/docs I've found only seem to use a single forward domain.

I've got both forward and reverse working, forward for a single domain, and reverse for whatever the subnet is.  My issue seems to be the following commands:

{

  "dhcp-ddns": { "enable-updates": true,
    "qualifying-suffix": "bogus.net",
    "override-client-update": true
},

These seem to be required in the DHCP4 config but then seem to override any settings in the ddns config

  "forward-ddns" : {
    "ddns-domains": [
        {
        "name": "bogus.net.",
        "dns-servers": [ { "ip-address": "re.dac.ted", "port": 53 } ]
        },
        {
        "name": "wireless.bogus.",
        "dns-servers": [ { "ip-address": "re.dac.ted", "port": 53 } ]
        },
        {
         "name": "bogus.",
         "dns-servers": [ { "ip-address": "re.dac.ted", "port": 53 } ]
          },
        ]
    },

The following is info is set under the "subnet" section for each:
-----
        {
            "name": "domain-name",
            "data": "bogus.net"
        },
-----
        {
            "name": "domain-name",
            "data": "bogus.wireless"
        },
-----
        {
            "name": "domain-name",
            "data": "bogus"
        },

I'm sure it's something simple I'm missing but been banging my head against it for a couple of days.  All forward DNS goes to bogus.net irrespective of the domain-name settings of the subnet."

Subtickets

Change History (3)

comment:1 Changed 3 years ago by tmark

After a bit of looking the domain-name option as described in RFC 2132 may not be the most appropriate value to use:

3.17. Domain Name

"This option specifies the domain name that client should use when resolving hostnames via the Domain Name System."

This is not quite the same as saying it is the domain in which a client's DNS mapping should be defined.

It is likely more flexible, and more symmetrical, to allow a subset of the D2 client-side parameters to be defined on both globally and at the subnet level.

ISC_DHCP uses the "ddns-domainname" statement to define the source of the qualifying suffix. It defaults to this:

"option server.ddns-domainname = config-option domain-name;"

Last edited 3 years ago by tmark (previous) (diff)

comment:2 Changed 3 years ago by hschempf

  • Milestone changed from Kea-proposed to Outstanding Tasks

Moving to outstanding, per Kea team meeting on 10/20/2016

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