If I have got a router out of the box (does not have any configuration), to configure this router which configuration is recommended (better or advisable) , to copy a txt file via TFTP to the running-config, or copy and paste from txt to the terminal of the router ?
Because there were an argue that : copy txt file via TFTP produces less error than copy and paste to a terminal.
Please do not involve in the explanations of how to configure them.
On a new router, you will need to enter a (minimal) config via the console to be able to use tftp.
When you are at it, and have the config at hand, you might as well configure it completely. For this scenario, I can see little advantage of using tftp.
The most advantageous use of tftp is when you need to modify an operational device. For that, I sometimes use copy tftp start. This allows you to put in a completely different configuration which can subsequently be activated by issueing a reload or switching the router off and on. In this way you can allow for unskilled or untrusted personnel to work on remote routers without letting them on the CLI.
If you are working directly on a console, I would go for the cut-and-paste.
If you are working on a remote terminal server, you can get big problems with cut-and-paste, depending on the size of the buffers in the terminal emulator and the flow control. But then TFTP might not be an option in those circumstances.
I see this problem a lot with those remote racks you can rent for CCIE lab practice. If I cut-and-paste a whole router config I usually end up with garbage. I find the best stategy is to paste the config one block at a time, i.e. one interface or one "router" block at a time.
The reason I am asking this question when I copied and pasted from a txt file to our router and issued a command show tech , I realized after while that 15 lines of ACLs entries were missing from the output of the show tech,,,,I do not why!!!!