Help setting up FTP

Question

FTP

Faced some problems when using ftp on the server. Configuration: Debian 5 32 + ISP Manager Lite

-Problems with hacking to file server larger than 6GB. Checked on different axes and FTP managers. The result is the same. I tried to download iso files weighing 5 GB - everywhere the same thing. Perhaps there is some limitation in the configs? But after installation, I did not change anything in FTP.
- Cannot transfer server to server. Let's say my friend has a router where certain files are stored and shared via FTP... I need to clear the transfer of this data to my server. After many unsuccessful attempts to fill in, it was not possible. So what could be the problem?
-How to secure ftp? I use sftp, but at the same time I know that I can log in using regular ftp ... How to secure ftp as much as possible? Enable brute-force protection, set 20-digit passwords, limit user rights… What else can you offer?

I think most problems are not solved at the ISP level. And what does she have to do with it anyway? The FTP server is considered separately or am I mistaken in something?

Thanks in advance for your help.

Answer 1

FTP does not support ftp to ftp transfer, let your friend fumble the file via samba or upload directly from the router.
To keep ftp safe, just turn it off, I always do that.
You have some vague fears.

Answer 2

Go to ftp and use ssh (scp).

Answer 3

look at the logs

Answer 4

-How to secure ftp?… What else can you suggest?

fail2ban, iptables

-Can't transfer server to server... So what could be the problem?

scp or wget doesn't help? Maybe a friend's port is closed for "external" or for you. Or you do not have rights to the folder you are transferring to, or there is no disk space ... As advised above, look at the logs.