First use sync command update the super block. Then use the eject utility. It is used for those removable media devices that do not have a manual eject button, or for those that do, but are managed by Volume Management.

1) Type command sync to write superblock or data to device (for floppy disk):

# sync;sync

2) Use eject command to eject (or unmount it) floppy:

# eject fd

3) To Remove / unmount the CDROM disk
Use eject command as follows:

# eject cd

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