CUCM 12.5 requires a specific boot process. Unlike Windows, you cannot simply copy files to a USB drive. Here is how to do it correctly.
Before you spin up your virtual environment, your underlying hardware and hypervisor must meet Cisco's rigorous specifications. CUCM 12.5 is designed to run primarily on . 1. Supported Hypervisors
Most files found on the Cisco Software Download page (like UCSInstall_UCOS_12.5.x.sgn.iso ) are .
Previously known as the Product Upgrade Tool (PUT), this is the primary portal for ordering bootable media if you have a valid contract. Cisco Software Central: You can browse for images at the Cisco Software Download cucm 12.5 bootable iso download
If you have a valid contract but only see upgrade images online, you must use the on Cisco's website to request the bootable media, which is granted based on your software subscription entitlements. 3. How to Make a Non-Bootable ISO Bootable
Primary and Secondary DNS IP addresses (Forward and Reverse lookups must be pre-configured on your DNS server).
Once the VM boots from the ISO, you will enter the Cisco Unified Communications OS installer blue-screen wizard. Ensure you have the following information prepared before starting: CUCM 12
Select "Proceed" to install version 12.5.
80 GB or 110 GB (Thick Provision Lazy Zeroed is recommended for production) OS Type Selection: Red Hat Enterprise Linux 7 (64-bit) 5. Step-by-Step CUCM 12.5 Installation Guide
Because UC operating systems handle mission-critical voice traffic, downloading a corrupted file can introduce erratic bugs or security vulnerabilities. Always verify the file integrity before uploading it to your hypervisor. Before you spin up your virtual environment, your
Open your official UCSInstall_UCOS_12.5.x file within the software.
Your CCO ID must be linked to an active service contract (such as Cisco Smart Net Total Care) that covers unified communications software updates.
A copy of the boot sector file (often extracted from an older bootable Cisco ISO, like a CUCM 10.x or 11.x bootable disk, commonly named isolinux.bin ). Step-by-Step Conversion Procedure