Overview

You may notice that you cannot establish connections to the database. One or more of the following symptoms may be observed:

• When you run ndb_mgm -e show, the database appears as not connected:
  

  [ndbd(NDB)] 2 node(s)
  id=2 (not connected, accepting connect from 10.XXX.XXX.XXX)
  id=3 (not connected, accepting connect from 10.XXX.XXX.XXX)

• Some alarms show "No database connections are available.".
  
  
  
• When you run tp_status, it shows that the server uptime is very short. That might happen if there was a recent power work.
  

Solution

Please create a support ticket so the support team works on the SPF nodes to make the NDB Cluster get back into service.

Testing

To verify the database servers are available again, follow these steps:

1. Run ndb_mgm -e show again. The database must not appear as not connected.
   

   [ndbd(NDB)] 2 node(s)
   id=2 @10.XXX.XXX.XXX (mysql-5.6.44 ndb-7.4.24, Nodegroup: 0, *)
   id=3 @10.XXX.XXX.XXX (mysql-5.6.44 ndb-7.4.24, Nodegroup: 0)

2. Run tp_status and check the server uptime.
3. The alarms that were showing "No database connections are available." must now be cleared.