iSCSI vSAN multipath

[socbizkaia]

Hello,

i am begining with iSCSI vSAN to provide some virtual machines with iSCSI LUNs. I have one cluster of 8 ESXi/vSAN hosts. My questions are realted to the configuration of iSCSI multipathing in vSAN:

• How many hosts/paths should I configure in my iSCSI initiator. It is convinient to use the 8 ESXi/vSAN hosts or only a subset of the cluster, for example, 3 ESXi/vSAN hosts? If I only use 3 nodes, perhaps I am loading these 3 hosts?
• I can't find information about the multipath configuration that I should apply in the iSCSI initiator against a vSAN iSCSI target: path_grouping_policy (failover, multibus, prio...), path_selector (round-robin, queue-lenght...), failback (inmediate, ...), prio(const, alua...)... Do you know any recommendation from VMware?

Thanks in advance.

Christian

[KabirAli82 · Accepted solution]

Hi,

So am i correct that you want to use vSAN iSCSI for VMs? Why not run the VMs directly on vSAN? This looks like an extra layer of possible failure.

As for how many hosts to use:

By default, the iSCSI service is disabled, and needs to be manually enabled by the administrator. Every host in the cluster has to participate in the iSCSI target. All hosts in the cluster also need to use same VMkernel adapter. VMware recommends creating a new VMkernel adapter for the vSAN iSCSI traffic. The VMkernel adapter must be the same interface number on all hosts in the cluster.

Have a look at:

vSAN iSCSI Target - VIT | VMware® vSAN™ Network Design | VMware

[socbizkaia]

Thanks for the link you provided! The details I needed appear in MPIO considerations | VMware® vSAN™ Network Design | VMware . 🙂