What do you mean by a file being displaced? Like do you want it to be unreadable, or unmodified, or just not deleted?
It’s not really possible to have a level of protection that would require more than sudo because with root access you bypass anything else.
You could put the files on an encrypted volume that uses a special password when it is mounted. Or you could use the chattr command to set special ext4 attributes that would make it unmodifiable (but could be removed with sudo). Or just record the file’s hash, and that way you know it hasn’t been modified later.
It seems like that port needs to be accessible from the public Internet. Your local computer probably has at least one more firewall between it and the Internet, running on your router. You need to also forward the port on your router, which is what it says in the second half of the guide.
How to prevent files from being displaced? This protection should (somehow) persist through disk cloning.
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[SOLVED] still cannot open a transmission port, what am I doing wrong?
os: xubuntu 24.04...