Kibana version: 4.1.1

OS version: suse 11

Original install method (e.g. download page, yum, from source, etc.): download

Description of the problem including expected versus actual behavior:

Our business data scale is very large, We use kibana to show the es data.
The kibana index only has 12 document,
But the kibana index usually became red, then kibana page did not work.

Why did the kibana index became red?