My friend gave me an AXIS 70U Documents Server. Quite old, yet perfectly usable. Updating them using their manual resulted in an obscure message:
500 Command unrecognized or not implemented. Passive mode refused.
Forcing ftp in active mode (the default back in the days), fixed the issue:
$ ftp -A 192.168.178.102 Connected to 192.168.178.102 (192.168.178.102). 220 AXIS 70U Network Document Server V3.00 Feb 09 2007 ready. Name (192.168.178.102:rick): root 331 User name ok, need password Password: 230 User logged in ftp> bin 200 TYPE set to I. ftp> put 7000.bin flash local: 7000.bin remote: flash 200 PORT command successful. 150 Opening data connection for flash (192,168,178,99,168,75), (mode binary). 221-Transfer complete, flash programming finished OK. Starting new software... 221 Reset, closing connection. 2262494 bytes sent in 68 secs (33.25 Kbytes/sec) ftp> quit 226 Transfer complete.