Linux – How to set default screen colours in putty/ssh

To change the color settings within a running PuTTY session:

1. Left click on the top left PuTTY icon (on my system, this looks like two computers with a connection between them.
2. Choose "Change Settings". This should bring up a menu with Categories of "Session", "Terminal", "Window", and "Connection". All these should be expanded to show the sub-categories.
3. Under the "Window" category, choose "Colours".

You should then see several check box options, and a select box with several items you can set to the values you want. You can click on the "System Colours" option to get the colors pushed down from the server. Otherwise you can select the individual items you want to change and give each one the colors you want.

Edit: As warren pointed out in a comment, if you want the settings you just set up to persist to later connections, go back to the "Sessions" category. You can then select either the "Default settings" or one of the specific sessions you have saved, and click on "Save" to retain those settings.

FWIW: I often save different settings for different sessions so that it's easy to tell them apart when I simultaneously have connections to several different computers open.

By default, PuTTY presents itself as xterm. The terminfo database, used by various programs to determine the terminal capabilities, says xterm supports eight colors only:

$ infocmp -1L xterm | grep max_colors

This means that even if your version of Xterm does support 256-color mode, programs won't know about it.

• The easiest fix is to set your $TERM environment variable to xterm-256color.

  (In your ~/.profile, you could use:
  if [ "$TERM" = xterm ]; then TERM=xterm-256color; fi)

• You can tell PuTTY to always identify itself as xterm-256color, via Configuration → Connection → Data → Terminal-type string.

  Note: If you use #1 or #2, and you connect to a server which doesn't have the apropriate terminfo entry, all TUI programs will break.

• You can also set the 't_Co' option in vim to 256 to override the terminfo value.

  if &term == "xterm"
      set t_Co=256
  endif
  

• Or you could edit the terminfo database.

  $ infocmp -L -1 xterm | sed -r 's/(max_colors)#[0-9]+/\1#256/' > /tmp/xterm
  $ tic /tmp/xterm
  

  The updated entry will be kept in ~/.terminfo.