C3900-universalk9-mz.spa.157-3.m8.bin Instant

15.7(3)M is a Dead-End release for 3900 series — no new features after 15.7(3)M, only security and critical bug fixes.

Additionally, this image support:

: The platform family. This image is exclusively compiled for the Cisco 3900 series, including models 3925, 3925E, 3945, and 3945E. It will not work on 1900, 2900, or any other series. C3900-universalk9-mz.spa.157-3.m8.bin

| Specification | Detail | | :--- | :--- | | | Cisco 3900 Series (ISR G2) | | Release Train | 15.7(3)M | | Release Type | Maintenance Release (MD) | | Feature Set | Universal (Crypto) | | File Size | Approximately 90 - 100 MB (varies slightly) | | RAM Requirement | Minimum 512MB to 1GB recommended (depending on enabled features). | It will not work on 1900, 2900, or any other series

Router boots to rommon 1 > instead of IOS. Cause: The universalk9 image is large. If you have old BootROM (ROMMON) version prior to 15.0(1r), it cannot decompress the image. Fix: Upgrade ROMMON first. Find C3900_RM2.srec.152-4r1 or newer from Cisco. Cause: The universalk9 image is large