Solution for less (tested for bootstrap 3.3.5):
First, override icons for carousel:
// Overloading "glyphicon" class with "fa".
.glyphicon
{
&:extend(.fa);
// Overloading "glyphicon-chevron-left" with "fa-arrow-left".
&.glyphicon-chevron-left
{
&:extend(.fa-chevron-left);
}
// Overloading "glyphicon-chevron-right" with "fa-arrow-right".
&.glyphicon-chevron-right
{
&:extend(.fa-chevron-right);
}
}
This part is taken from Slava Fomin answer, based on Steven Clontz's base code.
Next step: disable glyphicons loading:
//** Load fonts from this directory.
@icon-font-path: "../fonts/";
//** File name for all font files.
@icon-font-name: "fontawesome-webfont";
//** Element ID within SVG icon file.
@icon-font-svg-id: "fontawesomeregular";
Do not forget about lessc lazy loading: @icon-font-svg-id
and other vars will have the latest value you have set.