7.10.2 Adding servers
This subsection explains how to add servers to a hot-standby configuration that has already been configured.
When you add servers, you install the servers in both the active system and the standby system, and then you configure the environment.
- Organization of this subsection
(1) Preparations
If you use HA Monitor to inherit a shared disk and LANs that are used by the servers, the preparations described below are required. If you do not inherit a shared disk or LANs by using HA Monitor, these preparations are not needed.
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Add volume groups to the shared disk.
In a hot-standby configuration using HA Monitor, one volume group is switched for each server. Therefore, you must create volume groups for the servers that are added as needed.
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Obtain the alias IP addresses that are used by the servers.
HA Monitor inherits alias IP addresses. Because the servers use the same alias IP addresses in the primary system and the secondary system, at least one alias IP address is needed per server. The same server can also use multiple alias IP addresses.
(2) Settings required to add servers
This subsection explains the settings required to add servers that differ from when the entire system is newly configured.
There is a limit to the number of servers that can be run concurrently on a single host. Before you add a server, make sure that adding the added server will not exceed the maximum permitted number of servers per host, which is 16 by default. You can change this default value by changing the servmax operand value in the HA Monitor environment settings.
(a) Adding servers within the range of the maximum value
If adding servers does not exceed the maximum permissible number of servers, follow the procedure for Configuration steps when a server is added provided in 6.1 Configuration procedure. There is no need to terminate HA Monitor.
(b) Changing the maximum value
If you change the maximum value, you must follow the procedure for Configuration steps when a server is added provided in 6.1 Configuration procedure and you must also specify HA Monitor environment settings.
To do this:
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Terminate all servers running in the active and standby systems.
To ensure that all servers have terminated, execute the server and host status display command (monshow command) and check that all the servers on that host have terminated.
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Terminate the HA Monitors in the active and standby systems.
To ensure that the HA Monitors have terminated, check syslog for the KAMN050-I message issued for the HA Monitors on both hosts.
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Specify the settings required for adding servers and the HA Monitor environment settings.
Specify the settings by following the procedure for Configuration steps when a server is added provided in 6.1 Configuration procedure.
You must also perform the Create definition files (server) and Create definition files (HA Monitor) steps. In the Create definition files (HA Monitor) step, you must correct the servmax operand in the definition file used to specify the HA Monitor operating environment. For details about the servmax operand, see 8.3.1 HA Monitor environment settings (sysdef).