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In the Cloud Services Portal, click Manage -> IPAM/DHCP -> Global DHCP Configuration.
On the Global DHCP Configuration page, click Leases Advanced Configuration and configure the following settings for IPv4 or IPv6 leases:
Abandoned Reclaim Time: Enter the abandoned reclaim time and select the time unit from the drop-down list. The maximum lease time allowed is 5 years. When a DHCP server is configured with a pool of addresses the expectation is that the server is authoritative and has complete jurisdiction over these addresses. However, for various reasons, such as misconfiguration or a faulty client implementation that retains its address beyond the valid lifetime, devices may be connected that use those addresses without the server’s approval or knowledge. The event is reported, the IP address is in an abandoned state, and cannot be handed out to clients until the default value expires. Configure this field after which the server will recover the lease and mark it as available.
IPv4 Abandoned Reclaim Time: Specify the settings in hours or minutes.
IPv6 Abandoned Reclaim Time: Specify the settings in hours or minutes.
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