Configure the Cluster – Apache

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. In this configuration example, we will be protecting two (2) virtual IPs. First we will protect 192.168.197.150, which our Apache webserver will use. The second time through this wizard we will protect 192.168.197.151, which will be used by MySQL
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 a Second IP Resource

Repeat the procedure above to protect a 2nd IP resource.

This second time, protect 192.168.197.151, which is the IP address our MySQL database will later use.

As a result, your LifeKeeper GUI will display as follows, with both IP resources Active and protected on the Primary cluster node:

Create a Mirror and Begin Data Replication

In this section we will setup and configure the Data Replication resource, which be used to synchronize our Apache Webserver’s data between cluster nodes. The data we will replicate resides in the /var/www partition on our Primary cluster node

Please note:

• The source volume to be replicated must be mounted on the Primary server
• The target volume, which will received replicated data, must NOT be mounted on the Secondaryserver.
• The target volume’s size must equal to or larger than the size of its source volume.

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 Data Replication and click Next.

3. Follow the Data Replication wizard, and enter the following values:

Field	Recommended Entries or Notes
Switchback Type	Intelligent
Server	LinuxPrimary (Primary Cluster Node, i.e. Mirror Source)
Hierarchy Type	Select: “Replicate Existing Filesystem”
Existing Mount Point	At this step you will select the mounted partition to replicate. In our example, select “/var/lib/mysql”
Data Replication Resource Tag	Leave as default
File System Resource Tag	Leave as default
Bitmap File	Leave as default (Note: if using high speed SSD storage you will want to create a small partition and use it for bitmap placement, i.e. /bitmaps)
Enable Asynchronous Replication	Leave as default (Yes)

4. Click Next to begin creation of the Data Replication resource hierarchy. Status will be displayed in the GUI as follows:

5. Click Next to begin the process to Extend the Data Replication Resource. Select all default settings. When it asks for the target disk, select a free partition on your Target server which is the same size (or greater) than the Source Volume we are replicating. This partition should NOT be mounted on the Target system.

6. Continue through the wizard, and you will be prompted to select the network you would like replication to take place over. In general, it’s a best practice to separate your user/application and your replication traffic. In our example setup we will replicate over our backend network, 192.168.198.X

7. Click Next and continue through the wizard. Once completed, your resource hierarchy will look as follows

Create the Apache Hierarchy

In this section we will create an Apache resource hierarchy on the primary server and extend it to the backup server. This step will create a dependency on the IP resource created in previous the step.

*Important: The Apache web server should not be running at this time.

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 Apache Web Server 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, i.e. Mirror Source)
Webserver Binary Location	/usr/sbin/httpd (assumes a standard apache config)
Webserver Root Directory	/etc/httpd (assumes a standard apache config)
Root Tag	Leave as default

4. Click “Create” to begin resource hierarchy creation on the primary server. Once complete, click “Next” to extend this resource to the secondary server.

5. During the Extend Resource wizard, leave all settings as default.

6. Note: during the resource creation process, LifeKeeper extracted the existing configuration of the existing Apache webserver, and identified that it depends on the IP resource (192.168.197.150) and the Data Replication resource (/var/www) that were created in previous steps. These resources now appear underneath the newly created Apache resource, to indicate the dependency relationship.

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 for Linux 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/mysql. 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 MySQL Resource Hierarchy

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

*Important: At this point, MySQL 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 MySQL” above to review the process to configure and start MySQL as needed.

1. From the LifeKeeper GUI toolbar, click Create Resource Hierarchy.
2. Select MySQL 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)
Location of my.cnf	Enter “/var/lib/mysql”. Note that earlier in the MySQL configuration process we created a my.cnf file in this directory.
Location of MySQL executables	Leave as default (/usr/bin) since we are using a standard MySQL install/configuration in this example
Database tag	Leave as default

4. Select Create to define the MySQL 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 MySQL resource is now protected on both cluster nodes. Click Finish to exit the Extend wizard.
8. Note: LifeKeeper will automatically identify that the MySQL resource has a dependency on the FileSystem resource (/var/lib/mysql). The Filesystem Resource will appear underneath the MySQL resource in the GUI
9. Your resource hierarchy should look as follows:

Create the MySQL IP Address Dependency

In this step will define an additional dependency: that MySQL depends on a Virtual IP (192.168.197.151) so that the IP address follows the MySQL database should it move. This IP (.151) is the IP the webserver will use to access the MySQL database.

1. From the LifeKeeper GUI toolbar, right-click on the “mysql” 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 MySQL 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 Apache, MySQL, and their dependent resources: IP addresses, and Storage, both shared and replicated.

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