Allied Telesis AT-S99 - Manual (Page 278)

Chapter 11: Uploading and Downloading Files
278
After you’ve selected a download and provided the necessary
information, the management card begins to download the file(s) by
using the information in the TFTP Image Download tab to contact the
TFTP server.
Note
To prevent damaging a management card or a line card, do not
power off the chassis or remove a card while it is writing the file to
flash memory.