Configure the Cluster – PostgreSQL

Primary Server

Complete the following steps on the primary server to configure the cluster:

• Create TCP Communication (Comm) Path(s)
• Verify the Communication (Comm) Path(s)
  

Before you begin, SIOS recommends at least two TCP communications paths between each server within the cluster to each remote server for heartbeat redundancy.

*Important Supported configurations require that you define redundant comm. paths, so that the failure of a single communication line will not cause a split brain where resource hierarchies may come in-service on multiple servers simultaneously.

Access the LikeKeeper GUI

The LifeKeeper Graphical User Interface (GUI) is a Java based application that can be run as a native Linux application.

The LifeKeeper GUI is based on Java RMI with callbacks. Hostnames must be resolvable or you may receive a Java 115 or 116 error.

1. Verify that both short and fully qualified hostnames of all cluster nodes resolve to the proper locations

 # ping LinuxPrimary

 # ping LinuxPrimary.domain.com

 # ping LinuxSecondary

 # ping LinuxSecondary.domain.com

2. To start the LifeKeeper Linux GUI Application:

a. /opt/LifeKeeper/bin/lkGUIapp &

3. Enter the name of the server you wish to connect to (this field will be populated with the name of the server you are on, if you are running the GUI from a server with LifeKeeper installed) along with your root credentials and click OK.

Create Communication (Comm) Paths

4. Within the LifeKeeper GUI, from the File menu, select Connect. Enter the name of your Secondary server, login and password when the Cluster Connect window displays.

5. Within the LifeKeeper GUI, click the Create Comm Path button on the toolbar. You can also right click one of the servers and click Create Comm Path from the pop-up menu as well.

6. Select your Local and Remote Server(s) from the list box. If a server does not appear in the list box, you may enter it by typing its name and clicking the Add Server button. When using the Add Server procedure, you must make sure that the computer names for both network interfaces on the servers respond correctly when you ping them (from all of the partner server(s)) using the ping –a IP ADDRESS syntax. If they do not, this must be corrected prior to continuing. Click Next.

7. Select TCP for Device Type and Click Next.

8. Provide all the required information and click Next for the following series of dialog boxes. For each field in the dialog box you can click Help for further information or refer to the table below for an explanation or recommendation

9. After entering data in all the required fields, select Create. A message will display indicating the network communication path is successfully created. Click Next.

If you selected multiple Local IP Addresses or multiple Remote Servers and the Device Type was set to TCP, then the procedure will return you to the setup wizard the next Comm Path.

10. Select Done in the last dialog box.

Repeat this process until you have defined all the communication paths you plan to use. SIOS strongly recommends that you define at least two communication paths for redundancy.

Verify the Communications Paths

1. Verify that the communications paths are configured properly by viewing the Server Properties dialog box. From the LK GUI, select Edit, Server, Properties and then the Comm Paths tab.

2. Note the State displayed is ALIVE. You can also check the server icon in the right, main pane of the GUI. If only one comm path has been created, the server icon shows a yellow warning icon on the server icon, indicating that one comm. path is ALIVE, but there is no redundant comm path. The server icon will display a green heartbeat checkmark when there are at least two comm paths configured and ALIVE.

Create the LifeKeeper Hierarchy

Create and Extend an IP Resource

In LifeKeeper, create an IP resource and extend it to the secondary server by completing the following steps. This Virtual IP will have the ability to move between cluster nodes along the application that depends on it.

1. From the LifeKeeper GUI toolbar, click Create Resource Hierarchy.

The Create Resource Wizard dialog box will appear with a drop down list box displaying all recognized Recovery Kits installed within the cluster.

2. Select IP Address and click Next.

3. Enter the appropriate information for your configuration. The table below contains a list of the fields that display and additional information to assist you as you complete this procedure. Recommended values are also show below. You can also click the Help button for further information. Press Next to continue after entering the required information.

IP Creation Field Definitions

Field	Tips
Resource Type	Select IP Address as the resource type and click Next.
Switchback Type	Select Intelligent and click Next.
Server	Select the Server where the IP resource will be created. Select your Primary server and click Next.
IP Resource	Enter the virtual IP information and click Next Example 192.168.167.151 Note This is an IP address that is not currently in use anywhere on your network. This is the address that all clients will use to connect to the protected resources.
Netmask	The IP subnet mask that your TCP/IP resource will use on the target server. Any standard netmask for the class of the specific TCP/IP resource address is valid. In our sample configuration 255.255.255.0 is used for a subnet mask on both networks. Note: The subnet mask you choose, combined with the IP address, determines the subnet that will be used by the TCP/IP resource and should be consistent with the network configuration.
Network Connection	This is the physical Ethernet card that the IP address is interfacing with. Chose the network connection that will allow your virtual IP address to be routable. Select the correct NIC and click Next.
IP Resource Tag	Accept the default value and click Next. This value only affects how the IP is displayed in the GUI. The IP resource will be created on our Primary server.

4. LifeKeeper will create and validate your resource. After receiving the message that the resource has been created successfully, click Next when the following dialog box appears so that you can complete the process of Extending the IP Resource to our Secondary server, below.

Extending the IP resource will start automatically after you have finished creating an IP address resource if you clicked Next in the dialog box displayed above. You can also start this from an existing IP address resource by right clicking on the active resource and selecting Extend Resource Hierarchy.

Refer to the table below to complete the Extend IP Resource procedure.

Field	Recommended Entries or Notes
Switchback Type	Leave as “intelligent” and click Next
Template Priority	Leave as default (1)
Target Priority	Leave as default (10)
Network Interface	This is the physical Ethernet card that the IP address is interfacing with. Chose the network connection that will allow your virtual IP address to be routable. The correct physical NIC should be selected by default. Please verify and then click Next
IP Resource Tag	Leave as default.
Target Restore Mode	Select Enable and click Next.
Target Local Recovery	Select Yes to enable Local Recovery for the SQL resource on the Target server.
Backup Priority	Accept the default value.

5. After receiving the message Hierarchy extend operations completed, click Finish and then click Done

6. Your IP resource (192.168.197.151) is now fully protected and has the ability to “float” between cluster nodes as needed. Looking at the LifeKeeper GUI you will notice that the IP resource is Active on the Primary cluster node and Standby on the Secondary cluster node

Create the Shared Filesystem Resource Hierarchy

Create a Filesystem resource to protect the shared iSCSI filesystem and make it high available between cluster nodes. LifeKeeper leverages SCSI Persistent Group Reservations (PGR) to lock the LUN, ensuring that only the active cluster node for the storage resource can access it.

*Important At this point, the shared iSCSI LUN needs to already be mounted on the Primary Server. It should NOT be mounted on the Secondary Server. See section titled “Configure iSCSI initiator, discover and login to iSCSI target” above to review the steps involved.

1. From the LifeKeeper GUI toolbar, click Create Resource Hierarchy.
2. Select File System and click Next.
3. Proceed Through the Resource Creation wizard, providing the following values

Field	Recommended Entries or Notes
Switchback Type	Intelligent
Server	LinuxPrimary (Primary Cluster Node)
Mount Point	Select /var/lib/pgsql . Note that LifeKeeper scans the system for LUNS that are sharable between cluster nodes. The list of possible shared LUNS is presented automatically in this step of the wizard.

4. Select Create Instance to define this resource hierarchy on the Primary Server
5. Click Next to Extend the File System Resource to the Secondary Server
6. In the Extend Wizard, select “Accept Defaults”
7. As a result the File System resource is now protected on both cluster nodes. Click Finish to exit the Extend wizard.
8. Your resource hierarchy should look as follows:

Create the PostgreSQLSQL Resource Hierarchy

Create a PostgreSQL resource to protect the PostgreSQL database and make it high available between cluster nodes.

*Important At this point, PostgreSQL needs to be already running on the Primary Server. It should NOT be running on the Secondary Server. See section titled “Install, Configure, and Start PostgreSQL” above to review the process to configure and start PostgreSQL as needed.

1. From the LifeKeeper GUI toolbar, click Create Resource Hierarchy.
2. Select PostSQL Database and click Next.
3. Proceed Through the Resource Creation wizard, providing the following values

Field	Recommended Entries or Notes
Switchback Type	Intelligent
Server	LinuxPrimary (Primary Cluster Node)
PostgreSQL Executable	Leave as default (/usr/bin) since we are using a standard PostgreSQL
Location	install/configuration in this example. This field is used to specify the directory path containing the PostgreSQL executables.
PostgreSQL Client	Leave as default (/usr/bin/psql) . This field is used to specify the directory
Executable Location	path containing the PostgreSQL executable psql.
PostgreSQL Administration	Leave as default (/usr/bin/pg_ctl). This field is used to specify the
Executable Location	directory path containing the PostgreSQL executable pg_ctl.
PostgreSQL Data Directory	/var/lib/pgsql/data. This field is used to specify the location of the PostgreSQL data directory (datadir) that will be placed under LifeKeeper protection. The specified directory must exist and reside on a shared or replicated file system.
PostgreSQL Port 5432.	This field is used to specify the TCP/IP port number on which the postmaster daemon is listening for connections from client applications
PostgreSQL Socket Path	Leave as default (/tmp/.s.PGSQL.5432 ) . This field is used to specify the full path to the Unix- domain socket on which the postmaster daemon is listening for connections from client applications.
Enter Database Administrator User	Enter “postgres” . This field is used to specify a PostgreSQL Database Administrator User name for the specified database instance with connection and administrator privileges for the instance
PostgreSQL Logfile	Leave as default (/tmp/pgsql-5432.lk.log) . This field is used to specify the log file path that will be used for the PostgreSQL log file.
Database tag	Leave as default

4. Select Create to define the PostgreSQL resource hierarchy on the Primary Server
5. Click Next to Extend the File System Resource to the Secondary Server
6. In the Extend Wizard, select “Accept Defaults”
7. As a result the PostgreSQL resource is now protected on both cluster nodes. Click Finish to exit the Extend wizard.
8. Note: LifeKeeper will automatically identify that the PostgreSQL resource has a dependency on the FileSystem resource (/var/lib/pgsql). The Filesystem Resource will appear underneath the PostgreSQL resource in the GUI
9. Your resource hierarchy should look as follows:

Create the PostgreSQL IP Address Dependency

In this step will define an additional dependency: that PostgreSQL depends on a Virtual IP (192.168.197.151) so that the IP address follows the PostgresSQL database should it move.

1. From the LifeKeeper GUI toolbar, right-click on the “pgsql-5432” resource
2. Select “Create Dependency” from the right-click context menu
3. In the Child Resource Tag dropdown menu, select “ip-192.168.197.151”
4. Click Next
5. Click Create Dependency
6. Click Done
7. The Virtual IP address resource (192.168.197.151) will now appear underneath the PostgreSQL resource in the LifeKeeper user interface. This ensures that resources move together, and are started/stopped in the proper order.
8. Your resource hierarchy should look as follows

At this point in the Evaluation, we have fully protected PostgreSQL, and its dependent resources: IP addresses, and Shared Storage.

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