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I have done this before but it has been forever and I can't find how I used to do it. Using nmap, I have a list of ip addresses I want to scan on only port 21. My breakdown would be to tell nmap to check a txt file for the ip's and then scan each one for accessible ports on port 21 and return a list of those ports. In case there is a better way than I have stated here is more info on what I am doing. I used an old spider I wrote years ago to locate ftp's that are open (no user/pass) and it made me a txt file of the ones it found. Used to this list would mean I only had to ftp in and I was ok. But now for some reason the list it returned of ip's will only let me ftp into maybe 1 out of every 4 or 5. This spider I wrote back in 99 or 2000 so things have changed somewhere. I have not needed to do this for that long so it has been sitting. Now I have a need to locate open/unsecured ftps and have spent the day trying to find a better way between taking calls so I am finally asking for help! Thanks