Defining sqlhosts information for connection management of high-availability replication systems that use secure ports
You must define sqlhosts network-connectivity information for connection management of high-availability replication systems. 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
To use a file other than $INFORMIXDIR/etc/sqlhosts on a specific host, set the host's INFORMIXSQLHOSTS environment variable to the alternative file.
For this example, you are setting up Enterprise Replication between the primary servers of two high-availability clusters.
- server_1 (primary)
- server_2 (SD secondary)
- server_3 (HDR secondary)
- server_4 (RS secondary)
- server_5 (primary)
- server_6 (SD secondary)
- server_7 (HDR secondary)
- server_8 (RS secondary)
Procedure
- 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 server_1 onsoctcp host_1 port_1 s=6 server_2 onsoctcp host_1 port_2 s=6 server_3 onsoctcp host_2 port_3 s=6 server_4 onsoctcp host_3 port_4 s=6 server_5 onsoctcp host_4 port_5 s=6 server_6 onsoctcp host_4 port_6 s=6 server_7 onsoctcp host_5 port_7 s=6 server_8 onsoctcp host_6 port_8 s=6
- On the host of each Connection Manager and database server,
create a sqlhosts file alias entry for each database
server.For example:
#dbservername nettype hostname servicename options server_1 onsoctcp host_1 port_1 s=6 a_server_1 onsoctcp host_1 port_9 server_2 onsoctcp host_1 port_2 s=6 a_server_2 onsoctcp host_1 port_10 server_3 onsoctcp host_2 port_3 s=6 a_server_3 onsoctcp host_2 port_11 server_4 onsoctcp host_3 port_4 s=6 a_server_4 onsoctcp host_3 port_12 server_5 onsoctcp host_4 port_5 s=6 a_server_5 onsoctcp host_4 port_13 server_6 onsoctcp host_4 port_6 s=6 a_server_6 onsoctcp host_4 port_14 server_7 onsoctcp host_5 port_7 s=6 a_server_7 onsoctcp host_5 port_15 server_8 onsoctcp host_6 port_8 s=6 a_server_8 onsoctcp host_6 port_16
The aliases are used by the cdr utility, which cannot connect to a secure port. - On the host of each Connection Manager and database server,
create a sqlhosts file group entry for each cluster.
Add group options to each database server entry. Use the
i=unique_number
group-entry option to assign an identifier to the group for Enterprise Replication. Use thec=1
group-entry option for cluster groups, 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 cluster_1 group - - i=1,c=1,e=a_server_4 server_1 onsoctcp host_1 port_1 s=6,g=cluster_1 a_server_1 onsoctcp host_1 port_9 g=cluster_1 server_2 onsoctcp host_1 port_2 s=6,g=cluster_1 a_server_2 onsoctcp host_1 port_10 g=cluster_1 server_3 onsoctcp host_2 port_3 s=6,g=cluster_1 a_server_3 onsoctcp host_2 port_11 g=cluster_1 server_4 onsoctcp host_3 port_4 s=6,g=cluster_1 a_server_4 onsoctcp host_3 port_12 g=cluster_1 cluster_2 group - - i=1,c=1,e=a_server_8 server_5 onsoctcp host_4 port_5 s=6,g=cluster_2 a_server_5 onsoctcp host_4 port_13 g=cluster_2 server_6 onsoctcp host_4 port_6 s=6,g=cluster_2 a_server_6 onsoctcp host_4 port_14 g=cluster_2 server_7 onsoctcp host_5 port_7 s=6,g=cluster_2 a_server_7 onsoctcp host_5 port_15 g=cluster_2 server_8 onsoctcp host_6 port_8 s=6,g=cluster_2 a_server_8 onsoctcp host_6 port_16 g=cluster_2
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.cluster_1 a_server_1 user_1 password_1 cluster_1 a_server_2 user_2 password_2 cluster_1 a_server_3 user_3 password_3 cluster_1 a_server_4 user_4 password_4 cluster_2 a_server_5 user_5 password_5 cluster_2 a_server_6 user_6 password_6 cluster_2 a_server_7 user_7 password_7 cluster_2 a_server_8 user_8 password_8 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 server_4 a_server_4 user_4 password_4 server_5 a_server_5 user_5 password_5 server_6 a_server_6 user_6 password_6 server_7 a_server_7 user_7 password_7 server_8 a_server_8 user_8 password_8 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 a_server_4 a_server_4 user_4 password_4 a_server_5 a_server_5 user_5 password_5 a_server_6 a_server_6 user_6 password_6 a_server_7 a_server_7 user_7 password_7 a_server_8 a_server_8 user_8 password_8
- In each database server's onconfig file,
set the DBSERVERALIASES parameter to that database server's aliases.
For example:The onconfig file entry for server_1:
DBSERVERALIASES a_server_1
- 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 REPLSET my_replset { INFORMIXSERVER cluster_1,cluster_2 SLA sla_1 DBSERVERS=ANY } CLUSTER my_cluster_1 { INFORMIXSERVER cluster_1 FOC ORDER=ENABLED \ PRIORITY=1 } CLUSTER my_cluster_2 { INFORMIXSERVER cluster_2 FOC ORDER=ENABLED \ PRIORITY=1 }
The second Connection Manager's configuration file has the following entries:NAME connection_manager_2 REPLSET my_replset { INFORMIXSERVER cluster_1,cluster_2 SLA sla_2 DBSERVERS=ANY } CLUSTER my_cluster_1 { INFORMIXSERVER cluster_1 FOC ORDER=ENABLED \ PRIORITY=2 } CLUSTER my_cluster_2 { INFORMIXSERVER cluster_2 FOC ORDER=ENABLED \ PRIORITY=2 }
Add the following entries to each client application's host sqlhosts file:#dbservername nettype hostname servicename options sla_1 onsoctcp cm_host_1 cm_port_1 sla_2 onsoctcp cm_host_2 cm_port_2
- 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.For example:#dbservername nettype hostname servicename options g_sla onsoctcp - - c=1,e=sla_2 sla_1 onsoctcp cm_host_1 cm_port_1 g=g_sla sla_2 onsoctcp cm_host_2 cm_port_2 g=g_sla
Results
Client connection requests to @g_sla are directed to one of the Connection Managers. If connection_manager_1 receives the request, it uses sla_1 to provide the client application with connection information for the primary server. If connection_manager_2 receives the request, it uses sla_2 to provide the client application with connection information for a replication server.