This article describes the difference between Junos normal image Vs using secure image while format EX/QFX switches.

In Junos OS, secure.img and a normal Junos image (junos-*.tgz / .img) differ mainly in terms of security hardening, cryptographic enforcement, and intended use cases.

The Secure Junos image is a security-hardened Junos OS image that provides significant system security enhancements. Its Secure Boot implementation is based on the UEFI 2.4 standard and enforces secure boot and cryptographic validation. The image is cryptographically signed, and during boot, the device verifies the bootloader, kernel, and file system. Secure Boot is enabled by default on supported platforms.

The file name typically follows the format: junos-install-<platform>-secure.img

In contrast, the normal Junos image is the default operating system image used on most Juniper devices. It provides standard security features such as SSH access, user authentication, and role-based access control, and supports all common operational features.

File format for normal image: junos-<platform>-<release>.tgz / .img

The choice between the two should be based on security requirements, compliance obligations, and operational flexibility needs.

https://www.juniper.net/documentation/us/en/software/junos/junos-install-upgrade/topics/topic-map/junos-os-overview.html

https://apps.juniper.net/feature-explorer/feature/6957?fn=Secure%20boot%20for%20routing%20engines