Defining sqlhosts information for connection management of server sets

You must define sqlhosts network-connectivity information for connection management of server sets.

About this task

The Connection Manager's sqlhosts file must contain entries for all database servers that it connects to.

To use a file other than $ONEDB_HOME/etc/sqlhosts on a specific host, set the host's ONEDB_ SQLHOSTS environment variable to the alternative file.

Procedure

  1. On the host of each Connection Manager and database server, create sqlhosts file entries for each database server.
    For example:
    #dbservername   nettype    hostname   servicename   options
 standalone_1   onsoctcp   host_1     port_1

 standalone_2   onsoctcp   host_2     port_2

 standalone_3   onsoctcp   host_3     port_3
  2. On the host of each client application, create an sqlhosts file entry for each service-level agreement (SLA) in each Connection Manager configuration file.
    The first Connection Manager's configuration file has the following entries:
    NAME connection_manager_1
MACRO servers=standalone_1,standalone_2,standalone_3

SERVERSET ${servers}
{
   ONEDB_SERVER ${servers}
   SLA sla_1a DBSERVERS=standalone_1
   SLA sla_2a DBSERVERS=standalone_2
   SLA sla_3a DBSERVERS=standalone_3
}
    The second Connection Manager's configuration file has the following entries:
    NAME connection_manager_2
MACRO servers=standalone_1,standalone_2,standalone_3

SERVERSET ${servers}
{
   ONEDB_SERVER ${servers}
   SLA sla_1b DBSERVERS=standalone_1
   SLA sla_2b DBSERVERS=standalone_2
   SLA sla_3b DBSERVERS=standalone_3
}
    Add the following entries to each client application's host sqlhosts file:
    #dbservername  nettype   hostname   servicename  options
 sla_1a        onsoctcp  cm_host_1  cm_port_1
 sla_1b        onsoctcp  cm_host_2  cm_port_2

 sla_2a        onsoctcp  cm_host_1  cm_port_3
 sla_2b        onsoctcp  cm_host_2  cm_port_4

 sla_3a        onsoctcp  cm_host_1  cm_port_5
 sla_3b        onsoctcp  cm_host_2  cm_port_6
  3. On the host of each client application, create sqlhosts file group entries for each group of SLA entries, and add group options to the SLA entries. Use the c=1 group-entry option so that connection-attempt starting points in the list of group members is random. Use the e=last_member group-entry option so that the entire sqlhosts is not scanned for group members.
    For example:
    #dbservername  nettype   hostname   servicename  options
 sla_1         group     -          -            c=1,e=sla_1b
 sla_1a        onsoctcp  cm_host_1  cm_port_1    g=sla_1
 sla_1b        onsoctcp  cm_host_2  cm_port_2    g=sla_1

 sla_2         group     -          -            c=1,e=sla_2b
 sla_2a        onsoctcp  cm_host_1  cm_port_3    g=sla_2
 sla_2b        onsoctcp  cm_host_2  cm_port_4    g=sla_2

 sla_3         group     -          -            c=1,e=sla_3b
 sla_3a        onsoctcp  cm_host_1  cm_port_5    g=sla_3
 sla_3b        onsoctcp  cm_host_2  cm_port_6    g=sla_3

Results

Client connection requests to @sla_1 are directed to one of the Connection Managers. If connection_manager_1 receives the request, it uses sla_1a to provide the client application with connection information for the primary server. If connection_manager_2 receives the request, it uses sla_1b to provide the client application with connection information for a replication server.