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In Virtual datacenters view go to Networks → Private tab. Here you can select IPs and click the lock button to indicate that you would like to reserve them.
When you reserve IPs, you must provide a reason. You can select one or more VMs from the current tenant to indicate where the IPs might be used. The platform does not validate the selection or assign IPs to these VMs. The administrator must assign the IPs to VMs outside of the platform.
After you reserve IPs, the platform displays a padlock symbol beside the IP addresses.
To display a tooltip with a list of the VMs that the IPs were reserved for, click on the padlock symbol.
To release IPs, the user can select them and click the unlock button.
In Infrastructure view, on the private networks tab, the list of private IPs also displays a padlock symbol beside reserved IPs.