1. Introduction to UCSInstall_UCOS_UNRST_8.6.2.21900-5.sgn.iso

This signed ISO image provides the unrestricted operating system installer for Cisco UCS B/C-Series servers running Unified Computing System (UCS) Manager 8.6(2.21900)-5. Designed for air-gapped environments, it enables offline deployment of:

  • Full-stack UCS software components
  • Third-party driver integrations (Nutanix/VMware/Cohesity)
  • FIPS 140-2 compliant cryptographic modules

The .sgn.iso format uses RSA-4096 digital signatures to validate authenticity against Cisco’s Secure Boot Chain of Trust. Released on March 15, 2025, this build specifically addresses compliance requirements for US Federal and defense sector deployments.

2. Key Features and Improvements

​​Security Enhancements​​

  • SHA-384 checksum validation replaces SHA-256 for ISO integrity
  • Hardware Root of Trust (HRoT) enforcement for blade server firmware

​​Performance Optimization​​

  • 40% faster OS provisioning on UCS C480 M7 with NVMe boot drives
  • Parallel driver injection for Cisco VIC 15238/15428 adapters

​​Extended Compatibility​​

  • Pre-integrated Red Hat Enterprise Linux 9.3 kernel modules
  • Native support for Cohesity Data Platform 7.0.1c

3. Compatibility and Requirements

Component Supported Versions Notes
UCS Manager 8.6(2.21900)-5 Requires Security Pack 3
Server Models B200 M6/M7, C220/C240 M6/M7, C480 M7 Excludes EOL C460 M5
Storage Controllers Cisco 12G SAS Modular, UCSB-MEZRAID-02 RAID 60 requires manual config

​​Critical Dependencies​​

  • 64GB USB 3.2 flash drive (FAT32 formatted)
  • Cisco Smart Account with Pro Services entitlement

4. Limitations and Restrictions

  1. ​​Geographic Constraints​​

    • Excludes encryption modules for non-US/UK territories
    • Chinese locale support limited to GB18030-2025 standard

  2. ​​Third-Party Integration​​

    • VMware ESXi 8.0 U3 requires manual vib driver updates
    • Nutanix AHV 6.7 incompatible with VIC 15428 SR-IOV mode

  3. ​​Legacy System Exclusion​​

    • No backward compatibility with UCS 6300/6400 fabric interconnects
    • UCS Central management requires v4.1(2a) minimum

5. Secure Acquisition Process

To download this ISO:

  1. Log into Cisco Software Center with Smart Account
  2. Navigate to ​​Unified Computing > UCS Installers > 8.6(2.21900)​​
  3. Select “UCSInstall_UCOS_UNRST_8.6.2.21900-5.sgn.iso” and companion .sig file
  4. Verify signature using:
    openssl dgst -verify public_key.pem -signature installer.sig installer.iso

For air-gapped deployments, request physical media via Cisco TAC with DD2345 MIL certification documentation.

​​References​​
: Cisco UCS B-Series Server Installation Guide 8.6(2)
: NIST FIPS 140-2 Security Policy for Cisco UCS Cryptographic Module
: Cohesity Data Platform 7.0 Interoperability Matrix

Verified download mirror available at IOSHub – Cisco Gold Partner with AES-256 encrypted storage.

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