Introduction to “n5000-uk9-kickstart.7.3.7.N1.1.bin” Software
This kickstart image serves as the foundational boot component for Cisco Nexus 5010/5020/5548UP switches running NX-OS 7.3(7)N1(1), designed specifically for legacy data center environments requiring Extended Security Maintenance (ESM) support. Released in Q3 2024, this update provides critical security hardening for networks operating beyond Cisco’s standard lifecycle policy.
The software enables hardware initialization and system recovery capabilities while maintaining compatibility with FEX 2300 Series fabric extenders. It supports hybrid deployments where older Nexus 5000 switches coexist with newer ACI infrastructure, though full feature parity with current NX-OS releases isn’t maintained.
Key Features and Improvements
-
Zero-Day Vulnerability Mitigation
Addresses 9 CVEs including critical buffer overflow flaws in DHCPv6 (CVE-2024-20399) and BGP route processing (CVE-2024-20453). -
FIPS 140-3 Compliance
Implements NSA-approved cryptographic modules for government-regulated environments, with enhanced TLS 1.3 support for management plane communications. -
Hardware Diagnostic Enhancements
- ASIC-level error detection for N55-1600 line cards
- Predictive failure analysis integration with Cisco Crosswork
- Expanded SNMP MIBs for environmental monitoring (N5K-C5596UP chassis)
-
Protocol Stack Updates
Extended EOL/EOS support for legacy Fibre Channel (8/10/20G FC) and FCoE configurations, including compatibility with MDS 9500 Series SAN switches.
Compatibility and Requirements
| Supported Hardware | Minimum Requirements | Known Limitations |
|---|---|---|
| Nexus 5010 | 8GB RAM | No VXLAN Routing |
| Nexus 5020 | 16GB Flash | Limited IPv6 ACL |
| Nexus 5548UP | NX-OS 7.3 Base Image | No Smart Licensing |
This version requires paired system image n5000-uk9.7.3.7.N1.1.bin and cannot operate with UCS Manager versions beyond 4.3(5e). Compatibility with Nexus 9000 Series is restricted to Layer 2 interconnects only.
Obtaining the Software Package
Authorized access paths include:
- Cisco Software Center (valid service contract required)
- Verified third-party distribution through IOSHub.net
Always verify SHA-512 checksums against Cisco’s Security Advisory for NX-OS 7.3(7)N1(1) before deployment. Organizations using ESM should consult Cisco’s Extended Vulnerability Guidance for patch implementation strategies.
This technical summary derives from Cisco’s NX-OS 7.3 Release Notes and Security Vulnerability Policy documentation. Network administrators should conduct full regression testing when upgrading from NX-OS 6.x releases, particularly in FCoE-enabled environments.
