InfoScale™ 9.0 Virtualization Guide - Linux

Last Published:
Product(s): InfoScale & Storage Foundation (9.0)
Platform: Linux
  1. Section I. Overview of InfoScale solutions used in Linux virtualization
    1. Overview of supported products and technologies
      1.  
        Overview of the InfoScale Virtualization Guide
      2. About InfoScale support for Linux virtualization environments
        1.  
          About SmartIO in the Linux virtualized environment
        2.  
          About the SmartPool feature
      3. About KVM technology
        1.  
          Kernel-based Virtual Machine Terminology
        2.  
          VirtIO disk drives
      4. About InfoScale deployments in OpenShift Virtualization environments
        1.  
          Configuring iSCSI for OpenShift VMs
      5.  
        About InfoScale deployments in OpenStack environments
      6.  
        Virtualization use cases addressed by InfoScale
      7.  
        About virtual-to-virtual (in-guest) clustering and failover
  2. Section II. Implementing a basic KVM environment
    1. Getting started with basic KVM
      1.  
        Creating and launching a kernel-based virtual machine (KVM) host
      2.  
        RHEL-based KVM installation and usage
      3.  
        Setting up a kernel-based virtual machine (KVM) guest
      4.  
        About setting up KVM with InfoScale solutions
      5. InfoScale configuration options for a KVM environment
        1.  
          Dynamic Multi-Pathing in the KVM guest virtualized machine
        2.  
          DMP in the KVM host
        3.  
          SF in the virtualized guest machine
        4.  
          Enabling I/O fencing in KVM guests
        5.  
          SFCFSHA in the KVM host
        6.  
          DMP in the KVM host and guest virtual machine
        7.  
          DMP in the KVM host and SFHA in the KVM guest virtual machine
        8.  
          VCS in the KVM host
        9.  
          VCS in the guest
        10.  
          VCS in a cluster across virtual machine guests and physical machines
      6.  
        Installing InfoScale in a KVM environment
      7. Installing and configuring VCS in a kernel-based virtual machine (KVM) environment
        1.  
          How VCS manages virtual machine guests
    2. Configuring KVM resources
      1.  
        About KVM resources
      2. Configuring storage
        1.  
          Consistent storage mapping in the KVM environment
        2. Mapping devices to the guest
          1.  
            Mapping DMP meta-devices
          2.  
            Consistent naming across KVM Hosts
          3.  
            Mapping devices using paths
          4.  
            Mapping devices using volumes
          5.  
            Mapping devices using the virtio-scsi interface
        3.  
          Resizing devices
      3. Configuring networking
        1. Bridge network configuration
          1.  
            Host network configuration
          2.  
            Configuring guest network
        2.  
          Network configuration for VCS cluster across physical machines (PM-PM)
        3.  
          Standard bridge configuration
        4.  
          Network configuration for VM-VM cluster
  3. Section III. Implementing InfoScale an OpenStack environment
    1. Installing and configring resources in an OpenStack environment
      1.  
        About installing and configuring the OpenStack environment
      2.  
        About installing and configuring InfoScale on OpenStack VMs
  4. Section IV. Implementing Linux virtualization use cases
    1. Application visibility and device discovery
      1.  
        About storage to application visibility using InfoScale Operations Manager
      2.  
        About KVM virtualization discovery in InfoScale Operations Manager
      3.  
        About Microsoft Hyper-V virtualization discovery
      4.  
        Virtual machine discovery in Microsoft Hyper-V
      5.  
        Storage mapping discovery in Microsoft Hyper-V
    2. Server consolidation
      1.  
        Server consolidation
      2.  
        Implementing server consolidation for a simple workload
    3. Physical to virtual migration
      1.  
        Physical to virtual migration
      2.  
        How to implement physical to virtual migration (P2V)
    4. Simplified management
      1.  
        Simplified management
      2. Provisioning storage for a guest virtual machine
        1.  
          Provisioning VxVM volumes as data disks for VM guests
        2.  
          Provisioning VxVM volumes as boot disks for guest virtual machines
      3. Boot image management
        1.  
          Creating the boot disk group
        2.  
          Creating and configuring the golden image
        3.  
          Rapid Provisioning of virtual machines using the golden image
        4.  
          Storage Savings from space-optimized snapshots
    5. Application availability using Cluster Server
      1.  
        About application availability options
      2.  
        Cluster Server in a KVM environment architecture summary
      3.  
        Virtual-to-virtual clustering and failover
      4.  
        I/O fencing support for virtual-to-virtual clustering
      5.  
        Virtual-to-physical clustering and failover
      6.  
        Recommendations for improved resiliency of InfoScale clusters in virtualized environments
    6. Virtual machine availability
      1.  
        About virtual machine availability options
      2.  
        VCS in host monitoring the Virtual Machine as a resource
      3.  
        Validating the virtualization environment for virtual machine availability
    7. Virtual to virtual clustering in a Hyper-V environment
      1.  
        Installing and configuring Cluster Server with Microsoft Hyper-V virtual-to-virtual clustering
    8. Virtual to virtual clustering in an OVM environment
      1.  
        Installing and configuring Cluster Server for Oracle Virtual Machine (OVM) virtual-to-virtual clustering
      2.  
        Storage configuration for VCS support in Oracle Virtual Machine (OVM)
    9. Multi-tier business service support
      1.  
        About Virtual Business Services
      2.  
        Sample virtual business service configuration
      3. Recovery of Multi-tier Applications managed with Virtual Business Services in InfoScale Operations Manager
        1.  
          Service Group Management in Virtual Business Services
    10. Managing Docker containers with InfoScale Enterprise
      1.  
        About managing Docker containers with InfoScale Enterprise
      2. About the Cluster Server agents for Docker, Docker Daemon, and Docker Container
        1.  
          Supported software
        2.  
          How the agents make Docker containers highly available
        3.  
          Documentation reference
      3. Managing storage capacity for Docker containers
        1.  
          Provisioning storage for Docker infrastructure from the Arctera File System
        2. Provisioning data volumes for Docker containers
          1.  
            Provisioning storage on Arctera File System as data volumes for containers
          2.  
            Provisioning VxVM volumes as data volumes for containers
          3.  
            Creating a data volume container
        3. Automatically provision storage for Docker Containers
          1.  
            Installing the InfoScale Docker volume plugin
          2.  
            Configuring a disk group
          3.  
            Creating Docker containers with storage attached automatically
          4.  
            Avoid noisy neighbor problem by using Quality of Service support
          5.  
            Provision to create snapshots
          6.  
            Configuring Veritas volume plugin with Docker 1.12 Swarm mode
        4.  
          About using InfoScale Enterprise features to manage storage for containers
      4. Offline migration of Docker containers
        1.  
          Migrating Docker containers
        2.  
          Migrating Docker Daemons and Docker Containers
      5. Disaster recovery of volumes and file systems in Docker environments
        1.  
          Configuring Docker containers for disaster recovery
      6.  
        Limitations while managing Docker containers
  5. Section V. Reference
    1. Appendix A. Troubleshooting
      1.  
        InfoScale logs for CFS configurations in OpenStack environments
      2.  
        Troubleshooting virtual machine live migration
      3.  
        The KVMGuest resource may remain in the online state even if storage connectivity to the host is lost
      4.  
        VCS initiates a virtual machine failover if a host on which a virtual machine is running loses network connectivity
    2. Appendix B. Sample configurations
      1. Sample configuration for a KVM environment
        1.  
          Sample configuration 1: Native LVM volumes are used to store the guest image
        2.  
          Sample configuration 2: VxVM volumes are used to store the guest image
        3.  
          Sample configuration 3: CVM-CFS is used to store the guest image
      2.  
        Sample configurations for OpenStack environments
    3. Appendix C. Where to find more information
      1.  
        InfoScale documentation
      2.  
        Linux virtualization documentation
      3.  
        Service and support
      4.  
        About Services and Operations Readiness Tools (SORT)

VirtIO disk drives

VirtIO is an abstraction layer for paravirtualized hypervisors in Kernel-based Virtual Machine (KVM) technology. Unlike full virtualization, VirtIO requires special paravirtualized drivers running in each VM guest. VirtIO provides support for many devices including network devices and block (disk) devices. Using VirtIO to export block devices to a host allows files, VxVM volumes, DMP meta-nodes, SCSI devices or any other type of block device residing on the host to be presented to the VM guest. When SCSI devices are presented to a VM guest using VirtIO, in addition to simple reads and writes, SCSI commands such as SCSI inquiry commands can be performed, which allows VxVM in the guest to perform deep device discovery. Running VxVM and DMP on the host and on the VM guest provides for consistent naming of SCSI devices from the array to the host through to the VM guest.

InfoScale 9.0 supports VirtIO SCSI devices and VirtIO block devices with Linux KVM. virtio-scsi is a virtual SCSI HBA interface, which is the foundation of an alternative storage implementation for virtual machines. It replaces virtio-blk on Red Hat Enterprise Linux (RHEL) with improved scalability and provides standard SCSI command set support.

The VirtIO feature that is used in the context of InfoScale is dynamically adding devices. VirtIO disk devices can be both, added and removed, from a running VM guest dynamically, without the need for a reboot.

The VirtIO limitations in the context of InfoScale are:

  • Disk caching:

    When disks are exported to the VM guest with the cache enabled, the VxVM configuration changes may get cached on the KVM host and may not be applied to the disks. When disks are shared between more than one VM guest, such a configuration change is not visible from VM guests other than the one on which the change was made. To avoid potential configuration conflict, disable caching the host (cache=no) while exporting the disks.

  • SCSI commands:

    SCSI devices that are presented as VirtIO devices to a VM guest support a limited subset of the SCSI command set. The KVM hypervisor blocks the restricted commands.

  • DMP Fast Recovery with SCSI devices:

    DMP Fast Recovery bypasses the normal VirtIO read/write mechanism, performing SCSI commands directly against the device. If DMP Fast Recovery is used within the VM guest, caching in the host must be disabled (cache=none) to avoid data integrity issues.

  • Thin reclamation:

    Thin reclamation is not supported on VirtIO devices. The WRITE-SAME command is blocked by the hypervisor. This limitation may be removed in future releases of Linux.

  • Resizing devices:

    Linux does not support online disk resizing of VirtIO devices. To resize a VirtIO device, the VM guest must be fully shut down and restarted. Support for online resizing of block devices is under evaluation for Linux.

  • Maximum number of devices:

    You can use virtio-scsi to configure disk devices inside the KVM guest. For details on the maximum number of devices that can be used, refer to the KVM documentation.

  • VxFS known issue:

    In a KVM environment under heavy I/O load, data corruption may occur on VxFS file systems that are created on LUNs attached as VirtIO block devices. For details, refer to Case # 00945974 on the Red Hat Support site.