4.2 Adding a New Server to the Directory

A servers may be configured either locally, or in the PEM Server Directory:

•	Local servers typically reside on the same machine as the PEM client, and are considered to be unmanaged.

•	Servers residing in the PEM Server Directory are considered to be managed, and are available to all PEM users. Servers in the PEM directory will normally be bound to an agent to enable monitoring (and other PEM features).

The process of configuring a server, either managed or unmanaged, is referred to as adding or registering a server.

Please note: You must ensure the pg_hba.conf file of the server to be registered allows connections from the host of the PEM client. For information about modifying the pg_hba.conf file, please see Section 8.1.

To open the New Server Registration dialog, click on the Add Server button on the client toolbar, or select Add Server from the File menu.

Figure 4.6 - The Properties tab of the New Server Registration dialog.

The Properties Tab

Use fields on the Properties Tab (shown in Figure 4.6) to enter the connection details for the new server.

•	Enter a descriptive name for the server in the Name field; the descriptive name will be displayed in the tree control.

•	Enter the host name or IP address in the Host field.

•	Enter the listener port number of the PostgreSQL or Advanced Server host in the Port field.

•	Use the Service field to specify the name of a service configured in the pg_service.conf file.

•	Select a maintenance database with the drop-down list box in the Maintenance DB field.

•	Specify the Username that the new server will use when connecting to the database; the specified user must have membership in the pem-admin role.

•	Enter the password associated with the user in the Password field.

•	Check the box next to Store password to instruct the PEM client to store the password for future connections.

•	Check the box next to Store on PEM Server to instruct the PEM client to store the definition of the server on the PEM server.

If the connecting role is not a member of pem_admin (they are connected using the read-only pem_user role), or the user has not logged in to the PEM server, the server definition is stored for the current user only.

•	Specify a background color for the server using the Colour selector (optional).

•	Select a server group for the new server using the drop-down list box in the Group field. The new server will be displayed in the selected group in the PEM client tree control.

•	Use the Team field to specify a PostgreSQL role name. Only PEM users who are members of this role, who created the server initially, or have superuser privileges on the PEM server will see this server when they log on to PEM. If this field is left blank, all PEM users will see the server.

Tip: Do not click OK (yet) if you wish to register the server as a managed server. To register the server as a managed server, you must complete the PEM Agent tab, binding the server to a PEM agent.

Figure 4.7 - The SSL tab of the New Server Registration dialog.

The SSL Tab

Use fields on the SSL tab (shown in Figure 4.7) to specify any SSL options required.

•	Use the drop-down list box in the SSL field to select an SSL mode:

Specify:
require	To require SSL encryption for transactions between the server and the agent.
prefer	To use SSL encryption between the server and the agent if SSL encryption is available.
allow	To allow the connection to use SSL if required by the server.
disable	To disable SSL encryption between the agent and the server.
verify-ca	To require SSL encryption, and to require the server to authenticate using a certificate registered by a certificate authority.
verify-full	To require SSL encryption, and to require the server to authenticate using a certificate registered by a trusted certificate authority.

For more information about using SSL encryption, see Section 31.17 of the Postgres documentation.

•	If applicable, use the Server Root Certificate File field to access a file browser, and specify the location of the server root certificate.

•	If applicable, use the Server Certificate Revocation List field to access a file browser, and specify the location of the certificate revocation list.

•	If applicable, use the Client Certificate File field to access a file browser, and specify the location of the client certificate.

•	If applicable, use the Client Key File field to access a file browser, and specify the location of the client key file.

•	Check the box next to SSL Compression to instruct the server to compress the SSL data stream.

For more information about implementing SSL support, see Chapter 31.17 of the Postgres Core Documentation, available at the EnterpriseDB website at:

http://www.enterprisedb.com/docs/en/9.3/pg/libpq-ssl.html

Figure 4.8 - The SSH Tunnel tab of the New Server Registration dialog.

The SSH Tunnel Tab

Use the fields on the SSH Tunnel tab (shown in Figure 4.8) to implement SSH tunneling to the new server; check the box next to Use SSH tunneling to enable the fields:

•	Check the box next to Use SSH tunneling to instruct PEM to use SSH tunneling to communicate with the monitored server.

•	Specify the name or IP address of the proxy host (through which client connections will be forwarded) in the Tunnel host field.

•	Specify the port that should be used for the tunnel in the Tunnel port field.

•	Specify the name of a user with connection privileges for the tunnel host in the Username field.

•	Specify the type of authentication that will be used when connecting to the tunnel host in the Authentication field.

Select the radio button next to Password to specify that the PEM client will provide a password for authentication by the tunnel host. This is the default.

Select the radio button next to Identity file to specify that the PEM client will provide a valid private key file when connecting.

•	If the tunnel host is expecting a private key file for authentication, use the Identity file field to specify the location of the key file.

•	If the tunnel host is expecting a password, use the Password/Passphrase field to specify a word or phrase that will be provided to the tunnel host for authentication.

Figure 4.9 - The Advanced tab of the New Server Registration dialog.

The Advanced Tab

Use the fields on the Advanced tab (shown in Figure 4.9) to specify connection information for the new server:

•	Specify the address of the host in the Host Address field.

•	Check the box next to Connect now to instruct the PEM client to negotiate a connection for the new server after you have completed the New Server Registration form and clicked OK.

•	Check the box next to Restore env? to instruct PEM to restore the browser environment when you reconnect to this server. If you regularly use different databases on the same server you may want to deselect this option.

•

If you specify a role name in the Rolename field, PEM will connect to the server using the identity specified on the Properties tab; after establishing a connection with the server, the client will assume the identity and permissions of the role specified in the Rolename field.  The role specified on the Properties tab must be a member of the role specified on the Advanced tab.

•	Specify an SQL restriction in the DB restriction field to limit the databases displayed in the PEM client. For example, enter: 'live_db', 'test_db' to display only live_db and test_db in the PEM browser.

•	Specify the name of the PostgreSQL or Advanced Server service in the Service ID field on the Advanced tab. This allows the PEM server to stop and start the service.

On Unix systems, provide the name of the service script located in /etc/init.d

On Windows, provide the ID of the service. You can find the service ID in the Services Microsoft Management Console application.

The Postgres Plus Advanced Server installer uses a default service ID of ppas‑9.x, where x specifies the version number of the server. For example, the service ID of Advanced Server 9.3 is:

ppas-9.3

The EnterpriseDB one-click installer (for PostgreSQL) uses a default service ID of postgresql-9.x where x specifies the version number of the server. For example, the service ID of Advanced Server 9.3 is:

postgresql-9.3

Figure 4.10 - The PEM Agent tab of the New Server Registration dialog.

The PEM Agent Tab

Use fields on the PEM Agent tab (shown in Figure 4.10) to create a binding between the new server and a PEM agent. A binding provides the link between the PEM server and the PEM agent that allows the PEM server to monitor and manage that agent. The binding also provides the connection parameters that the agent uses when connecting to the PEM server.

It is important to note that the agent may use different connection credentials when connecting to the monitored server than the client uses. For example, the agent on a Unix host may use a Unix Domain Socket to connect to the server, while the client may connect via a connection pooler on an entirely separate host.

•

Check the box next to Remote monitoring ? to indicate that the PEM agent does not reside on the same host as the monitored server. When remote monitoring is enabled, agent level statistics for the monitored server will not be available for custom charts and dashboards, and the remote server will not be accessible by some PEM utilities (such as Audit Manager, Capacity Manager, Log Manager, Postgres Expert, and Tuning Wizard).

•	Select an Enterprise Manager agent using the drop-down list box to the right of the Bound Agent label. Each server should be assigned a unique agent.

•	Enter the IP address that the agent should use when connecting to the Postgres Plus host in the Host field.

Please Note: You may wish to specify a different Host address on the PEM agent tab than the address used on the Properties tab. For example, you can configure the PEM agent to connect via a Unix socket to the monitored server, while the client connects using an SSL connection to a forwarded port on an external firewall (that is not appropriate for the agent).

•	Enter the port that the server is listening for connections on. By default, the agent will use the port defined on the Properties tab.

•	Use the SSL field to specify an SSL operational mode; specify require, prefer, allow, disable, verify-ca or verify-full.

For more information about using SSL encryption, see Section 31.17 of the Postgres documentation.

•	Use the Database field to specify the name of the database to which the agent will initially connect.

•	Specify the name of the role that agent should use when connecting to the server in the Username field.

•	Specify the password that the agent should use when connecting to the server in the Password field.

•	Verify the password by re-entering it in the Confirm Password field. If you do not specify a password, you must configure the authentication for the agent manually (for example, by using a .pgpass file).

•	Use the Allow takeover option to specify whether or not the monitoring of the server may be taken over by another agent in a High Availability environment.

The PEM client will connect directly to the managed server, so the pg_hba.conf file must contain the appropriate entries to allow those connections. For information about modifying the pg_hba.conf file, see Section 8.1.

When you have specified the server details, click OK to add the connection.