C3900-universalk9-mz.spa.157-3.m8.bin Jun 2026

! Set boot parameter configure terminal boot system flash:C3900-universalk9-mz.spa.157-3.m8.bin config-register 0x2102 end

Built for the Cisco 3900 series, which includes the 3925 and 3945 routers. C3900-universalk9-mz.spa.157-3.m8.bin

: Binary executable file; the raw IOS kernel. feature-rich IOS version. However

: Support for next-generation High-Density PVDM3 modules and Multi-Gigabit fabrics. Lifecycle and Support C3900-universalk9-mz.spa.157-3.m8.bin

universalk9 means you can enable advanced security (SSL VPN, GETVPN, zone-based firewall) and UC features with the right license. No need to hunt for a separate “advanced IP services” image.

that need to run a stable, well-patched, feature-rich IOS version. However, because the platform and IOS are fully end-of-life, do not deploy it for new greenfield projects or in environments requiring active security vulnerability patches.