Install the war feature (and the sub-features it requires):
karaf@trun> feature:install war
Note: you can use the -v or --verbose
switch to see exactly what Karaf does, and this will show the war, http, and jetty
features being installed, along with dependent bundles.
Check that the features were installed:
karaf@trun> feature:list
State Name
...
[installed ] [2.2.9] http karaf-2.2.9
[installed ] [2.2.9] war karaf-2.2.9
...