Managing HP Serviceguard Extension for SAP for Linux (May 2013)

This will create files for the private (id.rsa) and public key (id_rsa.pub) in the user’s .ssh directory.
The public key then needs to be distributed to the other hosts. This can be accomplished by running
the command ssh-copy-id –i id_rsa.pub user@host. This will add the user’s public key
to the authorized_keys (not authorized_keys2) on the target host.
On each cluster node this has to be executed as the root user and host being one of the other
cluster nodes in turn. On each clusternode and for each external application server invoke the
ssh-copy-id … user@host command twice, replacing the user@host string with
<sid>adm@appserver and root@appserver.
It is also recommended to pre-populate the known hosts file (/etc/ssh/ssh_known_hosts) on each
cluster node by executing
ssh-keyscan list-of-remote-hosts >> /etc/ssh/ssh_known_hosts
This avoids the first login from the remote host hanging in fingerprint confirmation.
After you complete this section, you can login without using the password for:
• root user on all cluster nodes
• root and sidadm on external application servers.
Configuring external instances (sgesap/sapextinstance)
External dialog instances ("D" and "J" type) can be configured into an SGeSAP package using
the sgesap/sapextinstance module. These instances might have the same SID as used for
the package (values for thesap_ext_system and sap_system parameters are identical), or
the SID can be from a different instance (the values for sap_ext_system and sap_system
parameters are different). The external dialog instances can be started, stopped, and restarted
using the package, and also stopped when the package fails over to the node where the instance
is running. A restriction that applies to instances with a foreign SID is that these can only be stopped
if the package fails on the local node.
Any instances configured with the sapextinstance module are handled on a best effort basis.
Failing to start or stop an external instance will not cause the whole package to fail. Such instances
are also not monitored by a SGeSAP service monitor. If the sapcontrol usage attribute is enabled
(enabled per default on SGeSAP/LX), SGeSAP will try to use sapcontrol commands to start and
stop instances.
For instances on remote hosts, sapcontrol will use the –host option to control the remote instance.
Note this requires that the remote instance’s sapstartsrv is already running and the required
webservices (for starting and stopping the instance) are open for remote access from the local
host (For more information, see the SAP notes 927637 and 1439348). If remote access via
sapcontrol fails and fallback access via remote shell is enabled, the remote shell will be used
instead.
The sapextinstance module also uses the attributes configured in the sgesap/sap_global
module. The attribute sgesap/sap_global/sap_system is used as the default SID,
sgesap/sap_global/rem_comm as the communication mechanism from the cluster node to
the application server.
Serviceguard Manager or the CLI interface can be used to configure the module.
NOTE: deploysappkgs cannot configure this module.
Completing SGeSAP package creation (Phase 3b) 73