Final answer:
The 'show filesystems' or 'show flash:' command is used on Cisco devices to display information about free NVRAM and flash memory, including permissions for reading and writing data. This is essential for network administrators to monitor system space and manage updates and files.
Step-by-step explanation:
The command in question is the 'show filesystems' or 'show flash:' command used in Cisco network devices to display the amount of free NVRAM (Non-Volatile Random-Access Memory) and flash memory. When you input this command into a Cisco device's command-line interface (CLI), it provides detailed information about the file systems available, including space used, space free, and permissions for reading or writing data, specific to each filesystem including NVRAM and flash memory.
These commands are particularly helpful for network administrators to ensure that there is adequate space for system upgrades, configuration files, or any other necessary files. The output gives the administrator a good understanding of the current status of the device's memory and can help with maintaining the device's file system organization and health.