https://sw.kovidgoyal.net/kitty/faq/#i-get-errors-about-the-terminal-being-unknown-or-opening-the-terminal-failing-or-functional-keys-like-arrow-keys-don-t-work

https://wezfurlong.org/wezterm/config/lua/config/term.html

kitty set TERM to xterm-kitty by default, and TUI apps like viu, yazi, curses will try to search in the host's terminfo(terminal capability data base) for value of TERM to determine the capabilities of the terminal.

But when you ssh into a remote host, the remote host is very likely to not have xterm-kitty in its terminfo, so you will get this error:

'xterm-kitty': unknown terminal type

Or when you sudo xxx, sudo won't preserve the TERM variable, it will be reset to root's default TERM value, which is xterm or xterm-256color in most linux distributions, so you will get this error:

'xterm-256color': unknown terminal type

Error opening terminal: xterm-kitty.

NixOS preserve the TERMINFO and TERMINFO_DIRS environment variables, for root and the wheel group: nixpkgs/nixos/modules/config/terminfo.nix

For nix-darwin, take a look at https://github.com/LnL7/nix-darwin/wiki/Terminfo-issues

Solutions

Simplest solution, it will automatically copy over the terminfo files and also magically enable shell integration on the remote machine:

kitten ssh user@host

Or if you do not care about kitty's features(such as true color & graphics protocol), you can simply set TERM to xterm-256color, which is built-in in most linux distributions:

export TERM=xterm-256color

If you need kitty's features, but do not like the magic of kitten, you can manually install kitty's terminfo on the remote host:

# install on ubuntu / debian
sudo apt-get install kitty-terminfo

# or copy from local machine
infocmp -a xterm-kitty | ssh myserver tic -x -o \~/.terminfo /dev/stdin

README.md

Termianl Emulators

'xterm-kitty': unknown terminal type when ssh into a remote host or sudo xxx

Solutions

'xterm-kitty': unknown terminal type when `ssh` into a remote host or `sudo xxx`