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I just came to know that we can setup a 2 node window failover cluster without using shared storage (SAN)

In that case, how does services running on 1 node failover to another when their data is not available on another node ?

All in all, can window server failover clustering work without a shared storage ? Does it means that services are failover, and data readily available in node2's storage ?

I am on window server 2012 r2

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  • Which specific services do you want to failover?
    – Chopper3
    Mar 30, 2016 at 18:03
  • @chopper3 not exactly sure yet.. I am just thinking to have every services that can be failover to failover. but am thinking how does MS achive that without shared storage
    – tiongmaru
    Mar 31, 2016 at 2:47

2 Answers 2

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If you set up a cluster without shared storage then you are very limited as to what resources the cluster can protect. for example if you are running a VM called VM1 on NODE1 and the cluster node fails there is no way for NODE2 to get access to the VHDs and other Virtual machines files it would need in order to start VM1 itself. As other contributors have said setting up a two node cluster without shared storage can be done but only to practice the install of the Failover cluster role. as for the Quorum, in Server 2012R2 we use a dynamic Quorum. in a two node cluster without shared storage one of the cluster nodes looses its vote leaving just one voting member. There is some excellent info available in this link: https://technet.microsoft.com/en-us/library/dn265972.aspx#BKMK_2012

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  • thanks for the link. I just want to clarify - in a no shared storage cluster setup - as per your example above, does the VHDs of VM1 in node1 get copied over to node2 automatically or it will not be copied/sync to node2 at all ?
    – tiongmaru
    Apr 11, 2016 at 15:40
  • unless you intervene there will not be any VHD sync between Node1 and Node2. there is a feature called shared nothing live migration which you can use to move VMs between nodes if you plan on any maintenance of the Node, but you have to initiate that yourself. if you are setting this up to test clustering there are some very cheap iSCSI device you can buy that can provide shared storage. Apr 11, 2016 at 18:04
  • so in an actual outage event, there is really no incentive for me to have a cluster setup this way isn't it ? I thought there will be some sort of passive syncing happening in the background , for non-shared storage cluster..
    – tiongmaru
    Apr 12, 2016 at 1:29
  • That's correct in an actual outage you would need your VMs stored on shared storage in order for the 2nd Node to be able to bring them online. there is a new feature of 2016 called Storage Space Direct that would allow a cluster without shared storage and allow failover but not in 2012R2. Apr 12, 2016 at 7:34
  • Michael - thanks for reply. so there is no way to automate storage syncing between the 2 nodes in window server 2012 r2 (without the help of any 3rd party tools ) yea ?
    – tiongmaru
    Apr 12, 2016 at 12:19
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The cluster network handles failover.

You can setup a cluster without shared storage, that doesn't make it recommended, but it can work. You still need to create the cluster networks as needed. In this case, the transfer of things like VHDs and other files will transfer over the cluster network during a failover.

This isn't really a high availability cluster, though. Failover time will depend on the size of the servers being transferred and the link speed between the server. This also won't function as a decent disaster solution as one server going down likely won't have enough time to fail the servers over.

Keep in mind that even though the cluster is not using shared storage, it still needs to have some storage available to it. Otherwise, you won't be able to fail over storage dependent resources (such as virtual machines). You can add storage by selecting the Disks container and then clicking on the Add Disks link.

As you can see, it is relatively easy to set up failover clustering. The entire process can usually be completed in less than fifteen minutes.

Source

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  • And for the storage - wait some months. Server 2016, Storage Spaces Direct (shared and replicated discs) - solved.
    – TomTom
    Mar 30, 2016 at 18:33
  • sds requires at least four nodes - so 2016 may not be the solution. Mar 30, 2016 at 20:23
  • @Brandyn Baryski - what about the quorum ? the wsfc does not need a quorum ?
    – tiongmaru
    Mar 31, 2016 at 2:49
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    You can use Windows Failover Clustering without shared storage in it's common sense like dedicated hardware SAN/JBOD/NAS, however, as you properly mentioned, you still need your data to be accessible from all the nodes participating in the cluster. There are various tools capable to achieve such kind of scenario using local storage, even free ones like starwindsoftware.com/starwind-virtual-san-free.
    – Net Runner
    Apr 11, 2016 at 20:09
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    Actually it does a mirroring of local storage between both servers, so you do not need any dedicated one. Your local storage is converted to HA storage.
    – Net Runner
    Apr 12, 2016 at 14:17

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