Veritas InfoScale™ 7.4.1 Virtualization Guide - AIX
- Section I. Overview
- Storage Foundation and High Availability Solutions in AIX PowerVM virtual environments
- Section II. Implementation
- Setting up Storage Foundation and High Availability Solutions in AIX PowerVM virtual environments
- Supported configurations for Virtual I/O servers (VIOS) on AIX
- Dynamic Multi-Pathing in the logical partition (LPAR)
- Dynamic Multi-Pathing in the Virtual I/O server (VIOS)
- Veritas InfoScale products in the logical partition (LPAR)
- Storage Foundation Cluster File System High Availability in the logical partition (LPAR)
- Dynamic Multi-Pathing in the Virtual I/O server (VIOS) and logical partition (LPAR)
- Dynamic Multi-Pathing in the Virtual I/O server (VIOS) and Veritas InfoScale products in the logical partition (LPAR)
- Cluster Server in the logical partition (LPAR)
- Cluster Server in the management LPAR
- Cluster Server in a cluster across logical partitions (LPARs) and physical machines
- Support for N_Port ID Virtualization (NPIV) in IBM Virtual I/O Server (VIOS) environments
- About setting up logical partitions (LPARs) with Veritas InfoScale products
- Configuring IBM PowerVM LPAR guest for disaster recovery
- Installing and configuring Storage Foundation and High Availability (SFHA) Solutions in the logical partition (LPAR)
- Installing and configuring storage solutions in the Virtual I/O server (VIOS)
- Installing and configuring Cluster Server for logical partition and application availability
- Enabling Veritas Extension for ODM file access from WPAR with VxFS
- Supported configurations for Virtual I/O servers (VIOS) on AIX
- Setting up Storage Foundation and High Availability Solutions in AIX PowerVM virtual environments
- Section III. Use cases for AIX PowerVM virtual environments
- Application to spindle visibility
- Simplified storage management in VIOS
- About simplified management
- About Dynamic Multi-Pathing in a Virtual I/O server
- About the Volume Manager (VxVM) component in a Virtual I/O server
- Configuring Dynamic Multi-Pathing (DMP) on Virtual I/O server
- Configuring Dynamic Multi-Pathing (DMP) pseudo devices as virtual SCSI devices
- Extended attributes in VIO client for a virtual SCSI disk
- Virtual IO client adapter settings for Dynamic Multi-Pathing (DMP) in dual-VIOS configurations
- Using DMP to provide multi-pathing for the root volume group (rootvg)
- Boot device management on NPIV presented devices
- Virtual machine (logical partition) availability
- Simplified management and high availability for IBM Workload Partitions
- About IBM Workload Partitions
- About using IBM Workload Partitions (WPARs) with Veritas InfoScale products
- Implementing Storage Foundation support for WPARs
- How Cluster Server (VCS) works with Workload Patitions (WPARs)
- Configuring VCS in WPARs
- Configuring AIX WPARs for disaster recovery using VCS
- High availability and live migration
- About Live Partition Mobility (LPM)
- About the partition migration process and simplified management
- About Storage Foundation and High Availability (SFHA) Solutions support for Live Partition Mobility
- Providing high availability with live migration in a Cluster Server environment
- Providing logical partition (LPAR) failover with live migration
- Limitations and unsupported LPAR features
- Multi-tier business service support
- Server consolidation
- About server consolidation
- About IBM Virtual Ethernet
- About IBM LPARs with virtual SCSI devices
- Using Storage Foundation in the logical partition (LPAR) with virtual SCSI devices
- Using Storage Foundation with virtual SCSI devices
- Setting up DMP for vSCSI devices in the logical partition (LPAR)
- About disabling DMP for vSCSI devices in the logical partition (LPAR)
- Preparing to install or upgrade Storage Foundation with DMP disabled for vSCSI devices in the logical partition (LPAR)
- Disabling DMP multi-pathing for vSCSI devices in the logical partition (LPAR) after installation or upgrade
- Adding and removing DMP support for vSCSI devices for an array
- How DMP handles I/O for vSCSI devices
- Using VCS with virtual SCSI devices
- Physical to virtual migration (P2V)
- Section IV. Reference
How DMP handles I/O for vSCSI devices
On the VIO client, DMP uses the Active/Standby array mode for the vSCSI devices. Each path to the vSCSI device is through a VIO server. One VIO server is Active and the other VIO servers are Standby. An Active/Standby array permits I/O through a single Active path, and keeps the other paths on standby. During failover, I/O is scheduled on one of the standby paths. After failback, I/Os are scheduled back onto the original Active path.
The following command shows the vSCSI enclosure:
# vxdmpadm listenclosure all ENCLR_NAME ENCLR_TYPE ENCLR_SNO STATUS ARRAY_TYPE LUN_COUNT FIRMWARE ======================================================================= ibm_vscsi0 IBM_VSCSI VSCSI CONNECTED VSCSI 9 -
The following command shows the I/O policy for the vSCSI enclosure:
# vxdmpadm getattr enclosure ibm_vscsi0 iopolicy ENCLR_NAME DEFAULT CURRENT ============================================ ibm_vscsi0 Single-Active Single-Active
For vSCSI devices, DMP balances the load between the VIO servers, instead of balancing the I/O on paths. By default, the iopolicy attribute of the vSCSI array is set to lunbalance. When lunbalance is set, the vSCSI LUNs are distributed so that the I/O load is shared across the VIO servers. For example, if you have 10 LUNs and 2 VIO servers, 5 of them are configured so that VIO Server 1 is Active and VIO Server 2 is Standby. The other 5 are configured so that the VIO Server 2 is Active and VIO Server 1 is Standby. To turn off load sharing across VIO servers, set the iopolicy attribute to nolunbalance.
DMP dynamically balances the I/O load across LUNs. When you add or remove disks or paths in the VIO client, the load is rebalanced. Temporary failures like enabling or disabling paths or controllers do not cause the I/O load across LUNs to be rebalanced.