wsrep_ready OFF. How to fix?

Having this issue:

| wsrep_local_index            | 3                                                   |
| wsrep_provider_name          | Galera                                              |
| wsrep_provider_vendor        | Codership Oy <info@codership.com>                   |
| wsrep_provider_version       | 3.9(r93aca2d)                                       |
| wsrep_ready                  | OFF

How do I fix this?