Starting a member

Db2® members are started as part of a global db2start or an individual db2start command. This topic focuses on starting a single member.

About this task

When you issue a db2start (either for the instance or member) the database manager starts all the Db2 idle processes on the host and all of the cluster caching facilities (with active hosts) defined in the instance, if the idle processes and cluster caching facilities are not already running. If the cluster caching facilities cannot be started, the member start operation will fail. If the idle processes cannot be started on the home host of the member, the start operation will fail but Db2 cluster services will start the member in restart light mode on another host. (See Restart light for more information.)

Procedure

To start a specific member, issue this command:

db2start member member-id

Results

The database manager starts individual members on the host that is currently specified in the db2nodes.cfg file, even if that host is not the home host for the target member. In other words, a member that was previously running as a guest member on another host will be started on that host in restart light mode. If that home host of the member is active and ready to receive its resident member, Db2 cluster services will fail the member back to its home host.

Example

John, a DBA, has finished performing maintenance on a host with one member (member 0) defined on it. He has now restarted the instance on the host (

db2start
instance on host so1

). The member was shut down before the maintenance operations. He then queries the status of all members in the instance using

SELECT ID,  
       varchar(HOME_HOST,10) AS HOME_HOST, 
       varchar(CURRENT_HOST,10) AS CUR_HOST, 
       varchar(STATE,21) AS STATE, 
       ALERT 
FROM SYSIBMADM.DB2_MEMBER

and gets the output:

ID     HOME_HOST CUR_HOST     STATE      ALERT
------ --------- ------------ ---------- -----
     0 so1       so1          STOPPED    NO
     2 so2       so2          STARTED    NO
     4 so3       so3          STARTED    NO

     3 record(s) selected.

John issues this command to start member 0:

db2start
member 0

. He queries the status of all members in the instance using

SELECT ID,  
       varchar(HOME_HOST,10) AS HOME_HOST, 
       varchar(CURRENT_HOST,10) AS CUR_HOST, 
       varchar(STATE,21) AS STATE, 
       ALERT 
FROM SYSIBMADM.DB2_MEMBER

and gets the output:

ID     HOME_HOST CUR_HOST     STATE      ALERT
------ --------- ------------ ---------- -----
     0 so1       so1          STARTED    NO
     2 so2       so2          STARTED    NO
     4 so3       so3          STARTED    NO

     3 record(s) selected.