H3C SR6600 Fundamentals Configuration Manual page 140

The upgrading at the CLI falls into two categories:
Upgrade method
Software Upgrade
Through a System
Reboot
Software Upgrade by
Installing Hotfixes
Upgrade object
You need to reboot the whole system to upgrade the
Boot ROM
software of a device. This causes running service
program and
interruption during the upgrade process, and is not
system boot file
recommended.
Hotfix is a fast, cost-effective method to repair
software defects of a device. Compared with
software version upgrade, hotfix can upgrade the
System boot file software without interrupting the running services
of the device. In other words, it can repair the
software defects of the current version without
rebooting the device.
10-129
Description