Queries on vSAN

[Shakti21]

We need to use 2 nodes for vSAN but connectivity is the main area of concerns as we have only 1 Gig port and following is the make model of the switch Cisco switches (WS-C3560G-24PS).

Is it possible to directly connect those 2 nodes to bypass 10 Gig switch by using Cat cable or FC cable for 10 Gig network. Also why we need 10 Gig network for this solution in some forums i am seeing 1 Gig will work but vmware is recommending 10 Gig.

Both the nodes having below configuration :

SSD = 480 GB * 2

HDD = 300 GB * 8

RAM = 64 GB

1 GB NIC = 4 ports

10 Gig NIC = 2 ports

For Net-witness we are using other host having below configuration and on same host we will use backup solution:

SSD = 110 GB * 2

HDD = 300 GB * 5

RAM = 32 GB

CPU = 1

1 GB NIC = 2 Ports

vSAN Witness traffic, Public, VMotion, VSAN, Management, Multicast, Backup how it connected. And use of vSAN Witness traffic, VSAN, Multicast.

[IRIX201110141]

There is a supportet configuration for something called "2 node direct connect". Take a look to 2 Node Direct Connect .

There is some additonal network configuration needed because of the witness/ha isolations address is most likely within another subnet.

Just search for "vsan 2 node direct connect" grab the most rescent best practice.

Regards,

Joerg

[Shakti21]

Thanks Joerg, it means in 2 node structure there is no need of 10 Gig switch connectivity if servers are directly connected.

For witness, vmotion, management 1 Gig is sufficient.

[IRIX201110141]

Correct.

Regards,

Joerg

[depping]

and vMotion traffic is also supported across the direct connect link, so that would also remove that load from the 1GbE links.

[Shakti21]

For direct connectivity between servers following is the available with Lenovo Intel X550-T2 Dual Port 10GBase-T (RJ45), but checking on vSAN certified list this is not mentioned. Not sure which card need to be procure for 10 Gig connectivity and what type of CAT cable is used. Will it be Cross over cable or straight cable.

[Shakti21]

Also, can we use HDD in-spite of SSD in VSAN in our test environment.

[TheBobkin]

Hello Shakti21​,

Each Disk-Group requires an SSD or NVMe as cache-tier device - while it is technically feasible to mark a HDD as a Flash device I really wouldn't advise doing this on even test vSAN as the performance will be poor and results potentially erratic.

Bob