configure two NAS for backup

I have two nas with truenas core installed.
One NAS contains all the data I need to keep, the other is empty.
I would like to configure the empty NAS as a backup NAS and then ensure that the data is saved.
What is the best solution?
I read that there are two possibilities: rsync and replication.
From what I understand replication is better, can you help me configure it? Can I find some guide or video where they explain how to do it?

The NAS are on the same LAN network.
I need the backup to avoid losing data.

Perhaps this article is of use:

I think it’s for remote connections. I have the two NAS in the same network.

Doesn’t matter if it’s a remote site or a local replication. The process is the same. Simply use the IP addresses in question, establish a replication task with SSH, and once you know it works, you can reconfigure it to also use Netcat to speed it up. Either way, a replication task will always be faster than a rsync.

Oh, and snapshots have to have been enabled on the source machine, so that needs to be set up first and have run at least once before replication can happen.

On the source NAS (the one with the data) I have already set up some snapshots which remain saved for 2 weeks on the NAS itself.

Do I have to make the settings that the guide says from the backup NAS?
What is Netcat?
if I use replication then can I browse the smb folders?

  1. your question is unclear. Please rephrase.
  2. SSH creates a secure tunnel and Netcat then moves the files. Presumably, netcat is more efficient at this than SSH by itself. Could be a multithreaded process, for example.
  3. depends how you set up replication. By default, the destination is read only but you can traverse and open files on it. If you want the destination to be just like the source then you have to set that as part of the replication task.