Cisco Cucm Virtualization Requirements !!top!! -

show status show hardware show version active Then cross-reference with the (you’ll need a Cisco.com login). The Bottom Line CUCM in a VM is incredibly stable—if you follow the rules. Cisco’s requirements aren’t bloated; they exist because UC is real-time, intolerant of jitter, and demands deterministic resources.

Let’s break down exactly what you need to know. Cisco publishes a Unified Communications Virtualization Compatibility Matrix (updated quarterly). If your hardware, hypervisor, or CPU isn’t listed there for your specific CUCM version— it is not supported. cisco cucm virtualization requirements

Cisco maintains one of the most strict—and arguably most misunderstood—virtualization requirement documents in the industry. Ignoring it almost guarantees TAC will hang up on you (politely, but firmly). show status show hardware show version active Then

When in doubt:

Don’t be that engineer. ✅ Hardware listed on UCS compatibility matrix ✅ ESXi build exactly as per Cisco doc ✅ 1 vCPU per physical core – no overcommit ✅ Memory reservation = full VM memory ✅ Thick eager zeroed disks on low-latency storage ✅ NTP configured inside CUCM OS (not host sync) ✅ DRS set to partially automated or disabled for CUCM VMs Need to Check Your Current Environment? Run this from the CUCM CLI: Let’s break down exactly what you need to know

If you’ve ever deployed Cisco Unified Communications Manager (CUCM) in production, you already know: this is not a “throw it on any VMware cluster” situation.