6.5. NFS Configuration: Active-Active Example

Section 6.2 Using the NFS Druid described how to configure a simple NFS service using the NFS Druid. This section shows how to configure a second NFS service on another running cluster member. The second service has its own separate IP address and failover domain. This cluster configuration, called an active-active configuration, allows multiple cluster members to simultaneously export file systems. This most effectively utilizes the capacity of cluster. In the event of a failure (or planned maintenance) on any cluster member running NFS services, those services will failover to the active cluster member.

For this example, individual subdirectories of the mounted file system will be made accessible on a read-write (rw) basis by three members of a department. The names of the systems used by these three team members are ferris, denham, and brown. To make this example more illustrative, notice that each team member will only be able to NFS mount their specific subdirectory, which has already been created for them and over which they have user and group permissions.

Use the Cluster Configuration Tool as follows to configure this example NFS service:

  1. Verify that the cluster daemons are running in the Cluster Status Tool; if not, choose Cluster => Start Local Cluster Daemons.

  2. Choose Cluster => Configure to display the Cluster Configuration Tool.

  3. Choose the Services tab and, if services have already been defined, select one and click New. (If no services are defined, just click New.)

    1. Specify nfs_engineering in the Service Name field. This name was chosen as a reminder of the service's intended function to provide exports to the members of the engineering department.

    2. In this example, assume a failover domain named clu3_domain was previously created using the Cluster Configuration Tool, consisting only of member clu3 with both Restricted failover to only these members and Ordered Failover unchecked. In this way, clu3 is designated as the preferred member for this service. (Note that the nfs_accounting service is assigned to failover domain clu4_domain.) Choose clu3_domain from the Failover Domain list. (For more information on failover domains, refer to Section 3.9 Configuring a Failover Domain.)

    3. Specify a value of 30 in the Check Interval field to specify that the status of the NFS daemons should be checked every 30 seconds.

    4. The cluster infrastructure includes support for NFS services. Consequently, there is no need to create or specify a value for User Script when configuring an NFS service. Accept the default value of None.

    5. Click OK to complete this portion of the service configuration.

  4. In the Cluster Configuration Tool, select the service you just created, and click Add Child. On the Add Device or IP Address dialog box, choose Add Service IP Address and click OK.

    1. In the Service IP Address field, enter This example assumes a hostname of clunfseng is associated with this IP address, by which NFS clients mount the file system. Note that this IP address must be distinct from that of any cluster member.

    2. The default netmask address will be used, so accept the default of None.

    3. The default broadcast address will be used, so accept the default of None.

    4. Click OK to complete the service IP address configuration.

  5. In the Cluster Configuration Tool, select the nfs_engineering service and click Add Child. On the Add Device or IP Address dialog box, choose Add Device and click OK.

    1. In the Device Special File field, enter /dev/sdb11 which refers to the partition on the shared storage RAID box on which the file system will be physically stored.

      Leave the Samba Share Name field blank.

    2. In the Mount Point field, enter /mnt/users/engineering.

    3. From the FS Type menu, choose ext3.

    4. In the Options field, enter rw,nosuid,sync.

    5. Leave the Force Unmount checkbox checked.

    6. Click OK to complete this portion of the device configuration.

  6. In the Cluster Configuration Tool, select the device you just created, and click Add Child.

    Enter /mnt/users/engineering/ferris in the NFS Export Directory Name field and click OK.

    Repeat this step twice, adding NFS export directories named /mnt/users/engineering/denham and /mnt/users/engineering/brown.

  7. In the Cluster Configuration Tool, select the NFS export for ferris and click Add Child. The NFS Export Client dialog box is displayed.

    In the Client Name field, type ferris.

    In the Options field, type rw.

    Click OK.

  8. Repeat step 7 twice, specifying clients named denham and brown, respectively, each with the same permissions options (rw).

  9. Save the service by selecting File => Save in the Cluster Configuration Tool.

  10. Start the service from the Cluster Status Tool by highlighting the service and clicking Start.