DHCP-DDNS fails to create A records in power dns by silently dropping the NCR records.
Environment: Kea dhcp/ ddns -version 1.6.2 , powerdns 4.0.8 Setup: The Kea DHCP /DDNS are configured to update the A and PTR records for devices in Powerdns. Both have postgres backend.
We see the DNS records not getting updated in following issues/scenarios. **Issue 1: **
- I have a device ( that has a Client Identifier) that got a lease from DHCP server, the DDNS also updated the records to DNS server. The DDNS is configured for both forward and reverse dns.
- Due to some network connectivity issue with the DHCP server for a blip, the client is unable to renew when lease expires, and lease is in the reclaim lease bucket. However it is able to get through before the lease is removed and hence given i have same client id , the same ip address lease is extended and given to the client.
- However , I find that the A records for this device are removed by DDNS but the PTR records are still present.
- On further renewal expectation is that A records would be populated but this doesnt happen. The ddns-update is enabled in dhcp config and NCR is created , But this is not processed by D2 and hence the A records are never getting updated.
The only way I could get the A records back was to delete the lease in the DHCP lease records.
Can you tell me why the DDNS/D2 server failed to update the A records. How do I prevent this?Is there any configuration to ensure that D2 updates the A records. So though the lease is present for the device , it is no longer available for DNS resolution.
Also we have witnessed that the DHCID record for both A and PTR for device is same , is that expected?
Issue 2: The same issue is seen if the DHCP server has provided the leases but fails to update the DNS server the first time. In subsequent lease renewals we don't see the A/ PTR records getting updated for the missed updates. Is there any way to fix these issues? Issue: 3 We also see that updates are partially missed out where in Forward DNS is successfully updated but the Reverse dns fails due to I/O timeouts with DNS server. What could be reasons for this I/O timeouts. Also what would happen if we reload the config of the DHCP server when it is processing the packets.
Attached: Our configuration file, dhcp logs and the records files.