VMmanager 6: Administrator guide

Creating a cluster

A cluster is a group of servers in a single location. The key feature of such servers (cluster nodes) is their location and high data transfer speed between them.

Perform the following steps to create a cluster:

  1. Go to Clusters Create a cluster.
  2. Enter a cluster Name or press generate.
  3. Set the Time zone that will be used for cluster nodes and virtual machines (VMs) by default.
  4. Enter optional Notes.
  5. Select the OS that can be installed on virtual machines in the cluster.
  6. Enable the option Users can upload their ISO-images t o allow VM owners to connect their own ISO images to the VM. Read more in the article Mounting an ISO image.
  7. Select the Domains Template for VMs in this cluster. For example, if you specify the template .example.com, when you create a VM in this cluster, it will have a domain of the form vm_name.example.com.
  8. Enter the RAM overselling rate in the node. Read more in the article Overselling.
  9. Select the type of Distribution of VM on nodes:
    • homogeneous — VMs will be created on the most vacant node of the cluster;
    • successive — VMs will be created on the node of the cluster that is filled up the most. Read more about node selection in Selecting a cluster node for the virtual machine.
  10. Select the Storage type for VM disks. To edit the default storage settings, press . Read more in the article Storage types.

    Note

    One cluster can use only one storage type. All cluster nodes must have the same directory and/or volume group names for storing VMs, images and operating systems (OS).

     File storage settings
    1. Specify the Path for VM directory. Default value is /vm.
    2. Specify the Path to the images directory. Default value is /images.
    3. Specify the Path to the OS directory. Default value is /share.
     LVM settings
    1. Specify the Volume group name. Default value is lvm0.
    2. Specify the Path to the images directory. Default value is /images.
    3. Specify the Path to the OS directory. Default value is /share.
     Ceph settings
    1. Enter the monitor’s Server address in Ceph cluster.

    2. Enter the Root password to connect to the server, or press I want to use public SSH-key to create the ssh-key.
    3. Specify the Port for incoming ssh-connections.
    4. Specify the Path to the images directory .
    5. Specify the Path to the OS directory.
  11. Select a Network configuration type:
    • Switching a pool is allocated for the cluster, combining blocks of IP addresses from physical networks;

    • Routing — a cluster node is assigned subnet of IP addresses. Virtual machines on this node are allocated only the IP addresses from the specified subnet. This subnet routing type does not allow migrating virtual machines to other cluster nodes. Choose this type, if your cluster is located in the data center Hetzner or OVH.

      For more information please refer to the article Cluster network configurations;

      Note

      If you create a cluster in the data center OVH when preparing the server perform the steps described in the article Server requirements for the cluster.

    • IP-fabric — a pool is allocated for the cluster, combining blocks of IP addresses from physical networks. Routing between the nodes of the cluster is carried out via the iBGP protocol.

      Note

      Before creating an "IP-fabric" cluster, add the cluster settings to the Route Reflector equipment configuration: IP addresses of nodes and numbers of BGP autonomous systems.

       When selecting this type of configuration, specify the cluster network settings:
      1. Gateway IP address for the VM.
      2. MAC address of the gateway for the VM.

        Note

        VMmanager will assign the IP and MAC addresses of the gateway to all virtual interfaces on the cluster node and use this data only to route the VM inside the node. You can specify any addresses that will not conflict with those used in the cluster node.

      3. Number of BGP Autonomous system and BGP community .
      4. IP address and number of the Autonomous system of neighbors — Route Reflector equipment. To specify settings for more equipment, press Add session .
      5. Press Save .


      Example of IP-fabric configuration



  12. Enable the Second network interface option to create a cluster with the main and additional network interface. This will allow you to create several network cards in the VM. Read more in Main and additional network .
  13. Select IP pools for the virtual machine. If you have enabled the Second network interface option, specify the Pool for the main network and the Pool for the additional network separately. If you select "Routing" configuration type, you don't need to create a pool. Enter IP addresses for the virtual machine when connecting a server.

    Note

    If you plan to use one network for allocating public IP addresses and another for private ones, we recommend using the main network for public IP addresses, and an additional one for private ones.

  14. Click on Create.

Example of creating a cluster


Connect the nodes to the cluster. For more information please refer to the article Managing servers in the cluster.