If the boot image and Cisco IOS Software image do not match on the Cisco 7500 series router, some Versatile Interface Processors (VIPs) can be disabled.
If the boot image and the Cisco IOS Software images do not match on the Cisco AS5800 series router, the dial-shelf and the router shelf can have communication problems (Dial Shelf Interconnect Protocol (DSIP)).
In both platforms, it is important to have the main Cisco IOS Software image and the boot Cisco IOS Software image synchronized.
Unexplained anomalies may occur if the Cisco 7500 and AS5800 series routers have boot images that do not match with the main Cisco IOS Software image. This could causes disruptions in service.
To resolve this issue, perform these steps:
Verify whether the modules and cards are supported by the desired Cisco IOS Software Release by referring to the Software Advisor. The Software Advisor provides the minimum versions of Cisco IOS Software needed to recognize the hardware. If you have a router that supports a boot image, such as the Cisco 7500 or AS5800 series router, verify that the bootflash image supports the hardware installed.
Check the minimum amount of memory required by the main image and the boot image of the Cisco IOS Software and download it by referring to the Cisco IOS Upgrade Planner.
In case the bootflash is too small to store the boot image, save the boot image in the Personal Computer Memory Card International Association (PCMCIA) Flash, and configure the router to load the boot image from the PCMCIA Flash by issuing the boot bootldr global configuration command.
For practical examples to upgrade both the main image and the boot image in these platforms, refer to these documents: