/mcp• A 300 agent profile is not available. You cannot switch versions. • For a 100 agent profile, if you do not want to deploy Cloud Connect, there is no change. • Ensure that the reservation of CPU and memory adhere to the specifications mentioned in the Virtualization Wiki. Note • Install Unified CCX only on virtual machines. Unified CCX will not run on bare metal. • In the virtual machine, change the Guest OS version to match the OS version of Unified CCX. • You must manually adjust the CPU Limit within VMware for the ESXi host to "Unlimited". • DNS is mandatory. Before you upgrade, configure the domain name and DNS server IPs and ensure the forward and reverse lookups on the DNS server are correct. • Do not make any configuration changes during upgrade because changes are lost after upgrade. • Always ensure to perform the backup on the first node before you start upgrading the second node. • Upgrade Unified CCX during off-peak hours or during a maintenance window to avoid service interruptions. • In an HA deployment of Unified CCX, you must switch both the Unified CCX nodes to the newer version during the same maintenance window. If the contact center is expected to function with only the first node that is switched to the new version, ensure that the following conditions are met until the switch version on the second node is complete: • No agents are logged in to the second node. • The services, Cisco Finesse Tomcat, Cisco Unified CCX Engine, and Cisco Unified CCX Database are in Stopped state on the second node. • Upgrade Unified CCX and Cisco Customer Collaboration Platform in the same maintenance window and perform the upgrade on Cisco Customer Collaboration Platform first, followed by Unified CCX. • After the upgrade of Cisco Customer Collaboration Platform, unread and unhandled emails are downloaded from the mail server and added to Unified CCX. However, the draft emails are not downloaded. • Ensure that a valid Cisco Customer Collaboration Platform OVA is deployed for a successful install or upgrade. The upgrade stops if no Cisco Customer Collaboration Platform OVA is found in the deployment. • Both the nodes in a cluster must run the same release of Unified CCX. The only exception is while you are upgrading the cluster software, during which a temporary mismatch is allowed. • Upgrade VMware tools and change the NIC adapter type for Unified CCX after the refresh upgrade and before initiating the switch version. • For more information on Certificates, see Cisco Unified Contact Center Certificate Management Guide available at: https://www.cisco.com/c/en/us/support/docs/customer-collaboration/ unified-contact-center-express/118855-configure-uccx-00.html. Cisco Unified Contact Center Express Install and Upgrade Guide, Release 12.5(1) SU3 15 Unified CCX Upgrade Important Considerations for Upgrade