Introduction to n6000-uk9-kickstart.7.3.3.N1.1.bin Software
This kickstart image (n6000-uk9-kickstart.7.3.3.N1.1.bin) serves as the foundational boot component for Cisco Nexus 6000 Series switches running NX-OS 7.3(3)N1(1), specifically addressing critical vulnerabilities identified in Cisco Security Advisory CSCwd59323. Designed for data center deployments requiring Layer 2/Layer 3 protocol stability, this Q2 2025 release enhances Fabric Extender (FEX) integration while maintaining FIPS 140-2 Level 1 cryptographic validation.
Compatible with Nexus 6004/6001/6008 chassis, including N6K-C6004-96S and N6K-C60128T-2G platforms, this release introduces automated firmware validation for third-party QSFP+ optics. It serves as the mandatory boot image for organizations upgrading from NX-OS 6.x train versions with 40G/100G interface configurations.
Key Features and Improvements
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Memory Management Optimization
- Resolved buffer leakage in VXLAN BGP-EVPN Type-5 route processing (35% throughput improvement)
- Enhanced SNMPv3 counter polling efficiency through dynamic memory allocation
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FEX Compatibility Enhancements
- Added auto-negotiation support for N2K-C2348TQ-10GE modules in vPC configurations
- Eliminated version mismatch alerts during FEX failover events
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Security Updates
- Patched 5 CVEs including remote code execution vulnerability (CVE-2025-20356)
- Upgraded OpenSSL to 1.0.2zf with TLS 1.2 cipher prioritization
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Installation Optimization
- Reduced kickstart verification time by 45% through checksum caching
- Implemented pre-boot compatibility checks for 100G QSFP28 optics
Compatibility and Requirements
| Supported Hardware | Minimum Bootflash | Known Constraints |
|---|---|---|
| Nexus 6004 | 8GB | Requires CMPLD v3.18+ firmware |
| Nexus 6001 | 6GB | SFP+ ports 1-4 limited to 10G speed |
| Nexus 6008 | 12GB | 100G interfaces need QSFP28 optics |
This release discontinues support for N6K-C6001-64S chassis and requires NX-OS 6.2(12) as the minimum upgradable version. Compatibility issues exist with Brocade ICX 7750 switches in mixed network environments.
How to Obtain the Software
Licensed network administrators can access n6000-uk9-kickstart.7.3.3.N1.1.bin through Cisco’s Smart Software Manager. For immediate download with SHA-512 verification, IOSHub.net provides multi-CDN accelerated distribution with automated hash validation reports.
A $5 expedited processing fee enables priority queue access and technical compliance certification. Contact our network specialists for bulk licensing solutions or FEX deployment consultation.
This technical brief synthesizes data from Cisco Security Advisory 2025-002 and NX-OS 7.3(3)N1 Release Notes. Always verify cryptographic signatures against Cisco’s PSIRT portal before production deployment.
