Below is some information that is useful if you are having problems with web_input:

SplunkWeb cannot start

This can happen when a browser started by Website Input will not close. To fix this, look for running instances of the browser (e.g. Firefox) and the driver (e.g. geckodriver) and close them. Then restart Splunk.

Cannot execute Firefox on Linux

This may be due to Linux permissions. To debug this, run the following search:

index=_internal source=*/geckodriver.log

You may see messages like this:

1560552380246   mozrunner::runner       INFO    Running command: "/usr/bin/firefox" "-marionette" "-foreground" "-no-remote" "-profile" "/tmp/rust_mozprofile.gu7Y8H5bTvln" 
Running Firefox as root in a regular user's session is not supported.  ($HOME is /home/luke which is owned by luke.)

You may want to run the app under an another account.nAlternatively, see for how to fix this.

Other issues

You can use the views under the "Health" section of the navigation to identify potential problems.

Alternatively, you can run the following search and look for anything that looks like an error

index=_internal sourcetype=web_input_modular_input NOT (DEBUG OR INFO)

If no related errors are seen, then try looking at all of the logs and see if the input indicates that it is working:

index=_internal sourcetype=web_input_modular_input