How omit O.S. from ftp initial message

From: <emanuele.lombardi_at_casaccia.enea.it>
Date: Tue, 01 Feb 2000 12:04:40 +0100 (MET)

This question is concerning security in some sense. I noticed that
ftp-ing to our alphas t64 Unix (4.0d & 5.0) results in such messages:

220 HOSTNAME.DOMAIN FTP server (Digital UNIX Version 5.60) ready

I would like to omit the "(Digital UNIX Version 5.60)" string not to
help hackers knowing the O.S. of my machines.

For the same purpose I have modified /etc/gettydefs so that hackers
trying telnet are not aware of the kind of machine they are attacking.

cat /etc/gettydefs

default# B9600#B9600#\r\nWelcome to %h\r\n#default

console# B9600 HUPCL CS8 CLOCAL IXON OPOST ONLCR # B9600 SANE IXANY TAB3 CLOCAL #\r\n\r\n%v (%h) %t\r\n\r\n\rlogin: #console


The question is:
Is there any way to avoid the O.S. name from the ftp message?
I tried /etc/banner but its contents are displayed before the unwanted
line, not instead of it.

Any suggestions?
Thanks and ciao from Italy to everybody,

Emanuele
 
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Received on Tue Feb 01 2000 - 11:05:44 NZDT

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