02-04-2020 07:50 AM - edited 02-04-2020 07:52 AM
I do have a distributed setup of infoblox appliances (4 of them).
Unfortunately my capacity report shows 348,000 dhcp leases which do not reflect my current state.
Most of them are abandoned some are locked to mac addresses.
scanvengers are not deleting them.
I tried csv import deletion but it does not work for dhcp leases.
How can I delete them so I empty my databases?.
at the moment all four of them are over 100% utilization.
Thanks for the help
A Record/Substitute (A Record) Rule/Substitute (IPv4 Address) Rule 56
Access Control Item 14
CNAME Record/Substitute Domain Name/Block/Passthru Rule 269
DHCP Custom Option 604
DHCP Fingerprints 266
DHCP Lease 348602
DHCP Option Fingerprint 691
DHCP Range 67
DHCP Vendor Id Fingerprint 48
Fixed Address 2259
Host Address 46902
Host Alias 609
NS Record 57
PTR Record/Substitute (PTR Record) Rule 45
Zone Delegated Server 31
Zone SOA 79
IB-1410 / IB-820
02-04-2020 07:00 PM
Did you try enabling DHCP lease scavenging which can help you to automatically delete free and backup leases that remain in the database beyond the number of days or weeks that you specify. It can be enabled as below.
IP addresses are marked as Abandoned for one of two reasons:
1. Before a DHCP server offers a lease to the client, it sends an ICMP echo request to the IP Address. If the DHCP server receives an ICMP echo reply, the DHCP server marks the IP address as Abandoned.
2. After a client receives a 'DHCPACK' packet for a requested IP address, the client sends an ARP request to check if the requested IP is being used in the network. If the client gets an ARP response, the client sends a 'DHCPDECLINE' message to the DHCP server and the server marks the IP address as Abandoned.
The abandoned IPs will be reclaimed by the DHCP server only when all the free IPs in the network have been leased out. After all the free IPs in the network are leased out, the Infoblox DHCP server will try to reclaim the Abandoned IP's. To reclaim an abandoned IP, the appliance will again send an ICMP echo request to each abandoned IP Address in turn. If it does not get an echo reply, then the DHCP server will mark the IP as free and give it to the client that is requesting an IP Address. If the client receives an ARP response as detailed above, it will send a 'DHCPDECLINE' and the IP will again be marked Abandoned
These abandoned leases can be fixed from your end by checking the clients in concern from the network level.