vsphere-esxi-vcenter-server-55-storage-guide

Chapter 19 Working with Virtual SAN• At least one SAS or SATA Hard Disk (HDD). On each host, SSDs and HDDs are combined into diskgroups with a single SSD and up to six HDDs per a disk group. The capacity ratio of an SSD to HDDstypically depends on use cases and workloads, but the best practice is to use 1:10 ratio of SSD capacityto HDD in each disk group. For more information about disk groups, see “Managing Disk Groups,” onpage 183.• An SAS or SATA HBA, or RAID controller that is set up in non-RAID mode.Virtual SAN and Persistent LoggingIf you install ESXi on USB or SD devices and then allocate all local storage to Virtual SAN, you will not haveany local disk or datastore available for persistent logging. Configure a Dump Collector and a SyslogCollector to direct ESXi memory dumps and system logs to a server on the network, rather than to a localdisk. For information, see the vSphere Installation and Setup documentation.Virtual SAN Networking Requirements and Best PracticesVirtual SAN requires correctly configured network interfaces.The hosts in your Virtual SAN cluster must be part of a Virtual SAN network and must be on the samesubnet. On each host, configure at least one Virtual SAN interface. You must configure this interface on allhost in the cluster, no matter whether the hosts contribute storage or not.NOTE Virtual SAN does not support IPv6.Follow these guidelines:• Virtual SAN requires a private 1Gb network. As a best practice, use 10Gb network.• On each host, dedicate at minimum a single physical 1Gb Ethernet NIC to Virtual SAN. You can alsoprovision one additional physical NIC as a failover NIC.• You can use vSphere standard switches on each host, or you can configure your environment with avSphere Distributed Switch.• For each network that you use for Virtual SAN, configure a VMkernel port group with the Virtual SANport property activated.• Use the same Virtual SAN Network label for each port group and ensure that the labels are consistentacross all hosts.• Use Jumbo Frames for best performance.• Virtual SAN supports IP-hash load balancing, but cannot guarantee improvement in performance forall configurations. You can benefit from IP-hash when Virtual SAN is among its many consumers. Inthis case, IP-hash performs the load balancing. However, if Virtual SAN is the only consumer, youmight not notice changes. This specifically applies to 1G environments. For example, if you use four 1Gphysical adapters with IP-hash for Virtual SAN, you might not be able to use more than 1G. This alsoapplies to all NIC teaming policies that we currently support. For more information on NIC teaming,see the Networking Policies section of the vSphere Networking Guide.• Virtual SAN does not support multiple VMkernel adapters on the same subnet for load balancing.Multiple VMkernel adapters on different networks, such as VLAN or separate physical fabric, aresupported.• You should connect all hosts participating in Virtual SAN to a single L2 network, which has multicast(IGMP snooping) enabled. If the hosts participating in Virtual SAN span across multiple switches oreven across L3 boundaries, you must ensure that your network is configured correctly to enablemulticast connectivity. You can change multicast addresses from the defaults if your networkenvironment requires, or if you are running multiple Virtual SAN clusters on the same L2 network.For more information, see the vSphere Networking documentation.VMware, Inc. 177