vSAN maximun size = 64TB?

[lamode]

Hi guys,

Since vSAN 6.0 support max 1 datastore per cluster and Max volume size for VMFS is 64TB.

Does it means 64TB is the maximum for a single vSAN cluster? :smileyshocked:

[CHogan · Accepted solution]

No - of course not.

The VSAN datastore is not VMFS or NFS. It is an object store.

The maximums are discussed in multiple VSAN documents, but a rough calculation for maximum size is (number of hosts x number of capacity devices x size of capacity device)

HTH

Cormac

[saranantony]

What is the maximum RAW capacity of VSAN ?

B@elow query is not relevant to this topic

We are planning to have a DR setup with the storage capacity of 400 TB in production, production is in traditional san . However we are planning to move virtual san . Still i am not convinced with VSAN as i am an storage administrator basically?

Thanks
Saran

[zdickinson]

Good afternoon, I believe Cormac answered your question.  There is no "limit" to the size of a vSAN datastore.  It just depends on how big you want your fault domain to be.

We did vSAN in DR first and it great there, 21 TB datastore.  The one caveat, make sure your DR replication solution supports vSAN.  And even when they say they do, ask again, and make them prove.  Ours said they did, it turns out that they were using and old API for file operations.  That old API worked fine for traditional VMFS, but not for vSAN.  They fixed it soon enough.

The other thing I learned it that I love converged infrastructure, I don't want to manage it.  We were planning on vSAN at production, but instead will be going with VxRail from EMC.  Thank you, Zach.

[saranantony]

What would be the advantage of VSAN over traditional san or what makes to chose VSAN over Traditioanal one?  since i am from storage background unable to read the actual benefits of VSAN compared to Traditional.

Thanks
Saran

[elerium]

For me, the biggest advantage was cost and flexibility of both choosing components (SSDs and drives) and quantities of each that make sense to me to fit my use case. Traditional SAN you buy more storage than you need to plan for future storage. VSAN you can buy just what you need and easily upgrade adding 1 disk at a time or expanding additional nodes. As an example my remote offices are using 5 of 12 drive bays on nodes and expanding capacity only as necessary. I have the flexibility of increasing storage 1 disk at a time. Traditional SAN, i'd have to buy a smaller node limiting where upgrades involve buying new units or buy the full filled out node with wasted storage.

Also I really like the rebuild logic of VSAN, normally when a disk in an array fails, there's a RAID rebuild involving every drive which causes massive I/O on rebuild. VSAN only the contents of that single disk are rebuilt, if a 4TB disk fails, only 4TB of data is involved in the I/O resync process instead of an entire array of disks rebuilding for a day.

In terms of cost, my DR site is:

5 Dell R730xd nodes. Each with 1xIntel E5-2650, 384GB RAM, 2xIntel P3700 1.6TB NVMe, 14x4TB WD Re4, 10GB redundant networking using Arista switches and Cisco firewalls. Whole setup cost ~$155k (network equipment, VMWare Ent, VSAN Std licensing included) providing 50 cores CPU, 1.9TB RAM, 125TB (250TB raw) usable RAID1 storage and it's pretty damn fast. If you exclude compute + network + VSAN licensing from my cost to price out what I would have normally shopped for storage, that gives around $65k to buy 250TB raw from a storage vendor, good luck with that....

I have run into similar issues too as Zach has, make sure your DR software or any ESXi integrated software fully supports VSAN. Also I have had nearly every bug applicable on the VMware support KBs involving VSAN affect me and some are quite serious. Make sure your environment is fully patched and you stay up to date with the KB articles applying any necessary workarounds/hotfixes and contact support at 1st sign of problems, VSAN is still somewhat new and some (mostly minor) bugs.

[zdickinson]

Good afternoon, if you're only looking at storage; I don't know that there is an advantage of vSAN over traditional.  The advantages are in the converged infrastructure.  That's where you see the savings and ease of administration.  So don't compare vSAN to traditional storage.  Compare it to traditional storage, compute, networking, the entire stack.  Thank you, Zach.