Veritas Cluster

Cluster Information

Veritas cluster 4.0 can have upto 32 nodes.

LLT (Low-Latency Transport)

veritas uses a high-performance, low-latency protocol for cluster communications. LLT runs directly on top of the data link provider interface (DLPI) layer ver ethernet and has several major junctions:

Group membership services/Atomic Broadcast (GAB)

GAB provides the following:

High Availability Daemon (HAD)

The HAD tracks all changes within the cluster configuration and resource status by communicating with GAB. Think of HAD as the manager of the resource agents. A companion daemon called hashadow moniotrs HAD and if HAD fails hashadow attempts to restart it. Like wise if hashadow daemon dies HAD will restart it. HAD maintains the cluster state information. HAD uses the file to build the cluster information in memory and is also responsible for updating the configuration in memory.

VCS architecture

So putting the above altogether we get:

Service Groups

There are three types of service groups:

When a service group appears to be suspended while being brought online you can flush the service group to enable corrective action. Flushing a service group stops VCS from attempting to bring resources online or take them offline and clears any internal wait states.


Resources are objects that related to hardware and software, VCS controls these resources through these actions:

When you link a parent resource to a child resource, the dependency becomes a component of the service group configuration. You can view the dependencies at the bottom of the file.

Proxy Resource

A proxy resource allows multiple service groups to monitor the same network interface. This reduces the network traffic that would result from having multiple NIC resources in different service groups monitoring the same interface.

Phantom Resource

The phantom resource is used to report the actual status of a service group that consists of only persistent resources. A service group shows an online status only when all of its nonpersistent resources are online. Therefore, if a service group has only persistent resources (network interface), VCS considers the group offline, even if the persistent resources are running properly. By adding a phantom resource, the status of the service group is hsown as online.


All node within the cluster must have a unique scsi-initiator-id, to set the scsi-initiator-id follow below:

  1. At the OBP set the scsi-initiator-id to 6

OK> setenv scsi-initiator-id 6
OK> printenv scsi-initiator-id

  1. When the server has booted create and enter the following in /kernel/drv/glm.conf

name="glm" parent=/pci@1f,4000

  1. To check that the scsi-initiator-id has been set use the following command
  # prtconf -v          # search through the listing finding scsi-initiator-id


Before you install VCS make sure you have the following perpared:

To install VCS follow below, remember that both hosts must be able to root rsh into each otherwithout requesting for a password: -

  1. Start the VCS installation by entering

    # ./installVCS
  2. Enter the cluster name and the unique ID number

    Cluster name:             cluster1
    Unique ID:                1

  3. Enter the systems names that require clustering

    System names: sun1 sun2
  4. The software will now check each servers remote access and then install the software on each server.
  5. A list will appear detailing all the NIC's available. Select the FIRST then the SECOND private networks links

    First Link:           hme0
    Second Link:          qfe0

  6. Answer Yes to the next questions (Servers are identical)
  7. The LLT and GAB files will be copied and a successful message will appear