Defining sqlhosts information for high-availability clusters that use Distributed Relational Database Architecture™ (DRDA®) and secure ports
Connection Managers support Distributed Relational Database Architecture™ (DRDA®) connections for high-availability clusters. You must define sqlhosts network-connectivity information for connection management of high-availability clusters that use DRDA®. If Connection Managers, database servers, or client applications are outside of a trusted network, you must also create an encrypted password file for security.
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 $INFORMIXDIR/etc/sqlhosts on a specific host, set the host's INFORMIXSQLHOSTS environment variable to the alternative file.
Procedure
- On the host of each Connection Manager and database server,
create sqlhosts file entries for each database
server in the cluster, and specify the
s=6
secure-port option.For example:#dbservername nettype hostname servicename options server_1 onsoctcp host_1 port_1 s=6 server_2 onsoctcp host_3 port_2 s=6 server_3 onsoctcp host_5 port_3 s=6
- On the host of each Connection Manager and database server,
add DRDA® alias entries. Use
a DRDA® protocol for the
nettype
value, and specify thes=6
secure-port option.For example:#dbservername nettype hostname servicename options server_1 onsoctcp host_1 port_1 s=6 server_2 onsoctcp host_2 port_2 s=6 server_3 onsoctcp host_3 port_3 s=6 drda_1 drsoctcp host_1 port_4 s=6 drda_2 drsoctcp host_2 port_5 s=6 drda_3 drsoctcp host_3 port_6 s=6
- On the host of each Connection Manager and database server,
create sqlhosts file alias entries for each database
server and each DRDA® alias.
For example:
#dbservername nettype hostname servicename options server_1 onsoctcp host_1 port_1 s=6 a_server_1 onsoctcp host_1 port_7 server_2 onsoctcp host_2 port_2 s=6 a_server_2 onsoctcp host_2 port_8 server_3 onsoctcp host_3 port_3 s=6 a_server_3 onsoctcp host_3 port_9 drda_1 drsoctcp host_1 port_4 s=6 a_drda_1 drsoctcp host_1 port_10 drda_2 drsoctcp host_2 port_5 s=6 a_drda_2 drsoctcp host_2 port_11 drda_3 drsoctcp host_3 port_6 s=6 a_drda_3 drsoctcp host_3 port_12
- On the host of each Connection Manager, add group entries
for the groups of database servers and DRDA® entries.
Add group options to the individual entries. Use the
c=1
group-entry option, so that connection-attempt starting points in the list of group members is random. Use thee=last_member
group-entry option so that the entire sqlhosts is not scanned for group members.For example:#dbservername nettype hostname servicename options g_servers group - - c=1,e=a_server_3 server_1 onsoctcp host_1 port_1 s=6,g=g_servers a_server_1 onsoctcp host_1 port_7 g=g_servers server_2 onsoctcp host_2 port_2 s=6,g=g_servers a_server_2 onsoctcp host_2 port_8 g=g_servers server_3 onsoctcp host_3 port_3 s=6,g=g_servers a_server_3 onsoctcp host_3 port_9 g=g_servers g_drda group - - c=1,e=a_drda_3 drda_1 drsoctcp host_1 port_4 s=6,g=g_drda a_drda_1 drsoctcp host_1 port_10 g=g_drda drda_2 drsoctcp host_2 port_5 s=6,g=g_drda a_drda_2 drsoctcp host_2 port_11 g=g_drda drda_3 drsoctcp host_3 port_6 s=6,g=g_drda a_drda_3 drsoctcp host_3 port_12 g=g_drda
A password file that is encrypted through the onpassword utility is required for connectivity through secure ports. The entries in the previously shown sqlhosts file are represented in the following password file.g_servers a_server_1 user_1 password_1 g_servers a_server_2 user_2 password_2 g_servers a_server_3 user_3 password_3 server_1 a_server_1 user_1 password_1 server_2 a_server_2 user_2 password_2 server_3 a_server_3 user_3 password_3 a_server_1 a_server_1 user_1 password_1 a_server_2 a_server_2 user_2 password_2 a_server_3 a_server_3 user_3 password_3 g_drda a_drda_1 user_1 password_1 g_drda a_drda_2 user_2 password_2 g_drda a_drda_3 user_3 password_3 drda_1 a_drda_1 user_1 password_1 drda_2 a_drda_2 user_2 password_2 drda_3 a_drda_3 user_3 password_3 a_drda_1 a_drda_1 user_1 password_1 a_drda_2 a_drda_2 user_2 password_2 a_drda_3 a_drda_3 user_3 password_3
- In each database server's onconfig file,
set the DBSERVERALIASES parameter to that database server's aliases.
The onconfig file entry for server_1:
DBSERVERALIASES a_server_1,drda_1,a_drda_1
The onconfig file entry for server_2:DBSERVERALIASES a_server_2,drda_2,a_drda_2
The onconfig file entry for server_3:DBSERVERALIASES a_server_3,drda_3,a_drda_3
- 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 CLUSTER my_cluster { INFORMIXSERVER g_servers,g_drda SLA sla_primary_1 DBSERVERS=PRI SLA sla_primary_drda_1 DBSERVERS=PRI SLA sla_secondaries_1 DBSERVERS=SDS,HDR SLA sla_secondaries_drda_1 DBSERVERS=SDS,HDR FOC ORDER=ENABLED \ PRIORITY=1 }
The second Connection Manager's configuration file has the following entries:NAME connection_manager_2 CLUSTER my_cluster { INFORMIXSERVER g_servers,g_drda SLA sla_primary_2 DBSERVERS=PRI SLA sla_primary_drda_2 DBSERVERS=PRI SLA sla_secondaries_2 DBSERVERS=SDS,HDR SLA sla_secondaries_drda_2 DBSERVERS=SDS,HDR FOC ORDER=ENABLED \ PRIORITY=2 }
Add the following entries to each client application's host sqlhosts file:#dbservername nettype hostname servicename options sla_primary_1 onsoctcp cm_host_1 cm_port_1 sla_primary_2 onsoctcp cm_host_2 cm_port_2 sla_secondaries_2 onsoctcp cm_host_1 cm_port_3 sla_secondaries_2 onsoctcp cm_host_2 cm_port_4 sla_primary_1_drda drsoctcp cm_host_1 cm_port_5 sla_primary_2_drda drsoctcp cm_host_2 cm_port_6 sla_secondaries_2_drda drsoctcp cm_host_1 cm_port_7 sla_secondaries_2_drda drsoctcp cm_host_2 cm_port_8
- 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 thee=last_member
group-entry option so that the entire sqlhosts is not scanned for group members.#dbservername nettype hostname servicename options g_primary group - - c=1,e=sla_primary_2 sla_primary_1 onsoctcp cm_host_1 cm_port_1 g=g_primary sla_primary_2 onsoctcp cm_host_2 cm_port_2 g=g_primary g_secondaries group - - c=1,e=sla_secondaries_2 sla_secondaries_2 onsoctcp cm_host_1 cm_port_3 g=g_secondaries sla_secondaries_2 onsoctcp cm_host_2 cm_port_4 g=g_secondaries g_primary_drda group - - c=1,e=sla_primary_2_drda sla_primary_1_drda drsoctcp cm_host_1 cm_port_5 g=g_primary_drda sla_primary_2_drda drsoctcp cm_host_2 cm_port_6 g=g_primary_drda g_secondaries_drda group - - c=1,e=sla_secondaries_2_drda sla_secondaries_2_drda drsoctcp cm_host_1 cm_port_7 g=g_secondaries_drda sla_secondaries_2_drda drsoctcp cm_host_2 cm_port_8 g=g_secondaries_drda
Results
Client connection requests to @g_primary_drda are sent by drsoctcp protocol to one of the Connection Managers. If connection_manager_1 receives the request, it uses sla_primary_1_drda to provide the client application with connection information for the primary server. If connection_manager_2 receives the request, it uses sla_primary_2_drda to provide the client application with connection information for the primary server.