Cluster Configuration on SLES 9
Table of Contents
- Minimum System Requirements
3.1 SLES 10 Linux Installation
3.2 SLES 9.x Linux Installation
- Configuring iSCSI Target on a SLES 10 Server
- Configuring iSCSI Initiators on a SLES 9.x Server
- Configuring Clustering Services on SLES 9.x Linux
A cluster is two or more interconnected computers that create a solution to provide high availability, high scalability or both.
The advantage of clustering computers for high availability is seen if one of these computers fails, another computer in the cluster can then consume the workload of the failed computer. Users of the system see no interruption of access.
Cluster reduces unplanned service outages and planned outages for software and hardware maintenance and upgrades. This ensures that all services are available to users without any interruption.
This document helps providing an easy and user friendly means to setup a Cluster Environment for ZENworks Linux Management, FTP, HTTP, Samba servers, etc. which are basically related to a Linux platform.
2. Minimum System Requirements
Three server class machines:
- One SLES 10 (This would be used as Cluster Target. In a typical Customer deployment this can be a shared Memory).
- Two SLES 9SP3 (This would be used as Cluster Nodes).
Before installation of target on the machine, make sure that you have enough space to configure a common storage device. This machine will act as a target.
3.1 SLES 10 Installation (Target)
Install the SLES 10 server on the new hardware and select the following packages.
- yast2-iscsi server
3.2 SLES 9.x Linux Installation (Nodes)
Install SLES 9.x server on the new hardware and select following packages.
- Various Linux Tools
- For all the graphics, do the following:
- Right-click the graphic, click Format Picture
- Click the Layout tab, & select “In Line with Text”.
4. Configuring iSCSI Target on a SLES 10 server
Follow the steps below to configure the iSCSI target server:
Create a block device on the target machine.
- Type yast2 disk in the terminal.
- Create a new Linux partition and select Do not format.
- Do not mount the partition.
- Select partition size depending upon the usage.
- At the terminal type:
If the iSCSI target is not installed on the server, you are prompted to install it.click Continue to install the iSCSI target.
- Click the Service tab and select When Booting in Service Start.
- Go to Global and Click Next to continue.
- Click Targets, click Add, and enter the path as /dev/hdax as created in step 1.
- If there is already a target, then delete the target and add a new one.
- Click Next to finish the target server configuration.
- To check the iSCSI target has been installed, enter the following command at:
5. Configuring iSCSI Initiators on a SLES 9.x server
- Make sure that iSCSI is installed on both the Linux Machines(SLES9.x).
- Follow these steps on both the machines.
- To get target name on sles10 Linux open “cat /proc/net/iet/volume”.
or Open yast2 iscsi-server
- Copy target name and paste in iscsi.conf file.
- Save and close the file.
Open iscsi.conf file on Linux server and enter Discovery address and Target name. Discovery address is the IP address of NetWare server (iSCSI target) and target name is the name of iSCSI as shown above.
- vi /etc/iscsi.conf
- At the end of file type:
Discovery address= <NetWare server IP address> TargetName= <iscsi target name>
DiscoveryAddress =184.108.40.206 Target Name= iqn.1984-08.com.novell:iscsi-80ce1060-d68e-d911-bb75-0080481cd2d5.novell
Open iSCSI initiator file by executing vi /etc/initiatorname.iscsi and specify the DNS name of target i.e SLES 10 for the InitiatorName . parameter.
Start ISCSI on Linux servers.
- On Linux terminal type /etc/init.d/iscsi start
- In the Popup click YES to start ISCSI on Linux servers.
Select iSCSI partition and create ext3 file system and give about 8GB size. Select Format but don’t configure mount point. Leave mount point as blank. (If you configure mount point, entry will be made in fstab and partition will be mounted automatically after system reboots).
6. Configuring Clustering Services on SLES 9.x Linux
We have to perform the steps below on both of the nodes:
- Install heartbeat on both the nodes
- Select High-Availability packages at the time of installation
or when you run the steps below it will ask for installation, just press continue.
On the console type:
select start heartbeat on Booting.
Enter the node 2 host name
Select heartbeat medium as Broadcast eth0 and Add.
Press continue at the popup…
We need to add two resources
IPaddr::<Virtual IP> Filesystem::/dev/sdaX::<mountpoint>::ext3
Note: Make sure that mount point exists.
(Optional) If you need to configure STONITH, add Host name.
Start heartbeat using the command:
How can you know that heartbeat is running, if all the resources are mounted, or on which node it is running?
The Version of Heartbeat on SLES 9SP3 is very old i.e 1.2.3
It does not have a GUI based tool, but you can see all of the above in the log file.
Path for the heartbeat log: /var/log/ha-log or /var/log/ha-debug
Please see the below files for node and resource configuration.
For nodes: /etc/ha.d/ha.cf
For resources: /etc/ha.d/haresources