Let’s see the configuration of TFTP server, which can be useful to download an image on a device not directly accessible.
Router # conf t
Router (config) # tftp-server?
Flash: Allow URL file TFTP load requests
null: Allow URL file TFTP load requests
nvram: Allow URL file TFTP load requests
system: Allow URL file TFTP load requests
Router (config) # tftp-server flash:?
flash: c1700-Y7-mz.123-13.bin
It can also assign an ACL to filter requests:
Router (config) # tftp-server flash: c1700-Y7-mz.123-13.bin?
<1-99> IP access list of hosts Requesting
<1300-1999> IP expanded access list of hosts Requesting
alias alias file
Router (config) # tftp-server flash: c1700-Y7-mz.123-13.bin