Maria_dev is a read_only user.
You need enable an admin user: Log ssh into sandbox (user:root pass:hadoop) and run ambari-admin-password-reset from root home, then insert a password for admin ambari user.
After change, log into ambari with admin user, and you enable to use service action button :)
In sandbox 2.4 the default username and password marie_dev have a read permission
for that you need to reset the username and password for admin , you can do that by lancing the script
after that you can login to Ambari by the username and password you just entered ,and there you have you admin permission :)
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