We have one VC Cluster set up with VMFS and iSCSI.
We are thinking that NFS will buy us simpler backup (NetApp SNAP). This will be our second cluster.
Regarding this:
1. will we be able to migrate VMs (cold) from VMFS to NFS so we could eventually get rid of the VMFS all together ?
2. Are there any drawbacks to NFS over VMFS (vmotion, HA, DRS etc all work the same) ?
3. Does NFS require same type of setup (iSCSI initiator, a SC, and Kernel also like our VMFS we have set up currently) ?
Note that VMworld 2007 (which I attended) had plenty of presenters touting NFS of VMFS and they all claimed performance was not an issue except over a WAN. WAN is not a concern for us.
Check out
http://www.vmware.com/pdf/vi3_301_201_server_config.pd
f starting on page 132.
ESX still creates VMFS partitions on NFS.
Are you sure about that?
I don't think NFS volumes were formatted as VMFS.
From the config pdf page 91:
File System Formats
Datastores that you use can have the following file system formats:
VMFS ESX Server deploys this type of file system on local SCSI disks, iSCSI
LUNs, or Fibre Channel LUNs, creating one directory for each virtual machine.
VMFS is a clustered file system that can be accessed simultaneously by multiple
ESX Server systems.
For more information on VMFS, see VMware File System on page 97.
As an alternative to using the VMFS-based datastore, your virtual machine can
have direct access to raw devices using a mapping file (RDM) as a proxy. For more
information on RDMs, see Raw Device Mapping on page 151.
NFS ESX Server can use a designated NFS volume located on an NFS server. ESX
Server mounts the NFS volume creating one directory for each virtual machine.
From the viewpoint of the user on a client computer, the mounted files are
indistinguishable from local files.
Message was edited by:
pdrace
We have one VC Cluster set up with VMFS and iSCSI.
We are thinking that NFS will buy us simpler backup
(NetApp SNAP). This will be our second cluster.
Regarding this:
1. will we be able to migrate VMs (cold) from VMFS to
NFS so we could eventually get rid of the VMFS all
together ?
I'm not sure about this but I would think you could.
2. Are there any drawbacks to NFS over VMFS (vmotion,
HA, DRS etc all work the same) ?
All should work assuming the NFS volumes are available to all the hosts in a cluster.
3. Does NFS require same type of setup (iSCSI
initiator, a SC, and Kernel also like our VMFS we
have set up currently) ?
No you don't need these for NFS.
Note that VMworld 2007 (which I attended) had plenty
of presenters touting NFS of VMFS and they all
claimed performance was not an issue except over a
WAN. WAN is not a concern for us.
I would have liked to try NFS on our NetApps but I don't have a license which is pretty pricey.
Check out http://www.vmware.com/pdf/vi3_301_201_server_config.pdf starting on page 132.
ESX still creates VMFS partitions on NFS.
All of the VMotion, HA, DRS features work the same.
You can cold migrate VMs between local VMFS/iSCSI/FC to NFS.
Check out
http://www.vmware.com/pdf/vi3_301_201_server_config.pd
f starting on page 132.
ESX still creates VMFS partitions on NFS.
Are you sure about that?
I don't think NFS volumes were formatted as VMFS.
From the config pdf page 91:
File System Formats
Datastores that you use can have the following file system formats:
VMFS ESX Server deploys this type of file system on local SCSI disks, iSCSI
LUNs, or Fibre Channel LUNs, creating one directory for each virtual machine.
VMFS is a clustered file system that can be accessed simultaneously by multiple
ESX Server systems.
For more information on VMFS, see VMware File System on page 97.
As an alternative to using the VMFS-based datastore, your virtual machine can
have direct access to raw devices using a mapping file (RDM) as a proxy. For more
information on RDMs, see Raw Device Mapping on page 151.
NFS ESX Server can use a designated NFS volume located on an NFS server. ESX
Server mounts the NFS volume creating one directory for each virtual machine.
From the viewpoint of the user on a client computer, the mounted files are
indistinguishable from local files.
Message was edited by:
pdrace
NFS is not formatted as VMFS. Not sure about the performance difference between NFS and VMFS, VMware pushes VMFS as a high performance file system so I would say that VMFS is faster. You cannot run DRS or HA on NFS, you can use VMotion.
3. Does NFS require same type of setup (iSCSI
initiator, a SC, and Kernel also like our VMFS we
have set up currently) ?
No you don't need these for NFS.
Correction you do need vmkernel for NFS access. You don't need an additional SC or ISCSI initiators.
NFS is not formatted as VMFS. Not sure about the
performance difference between NFS and VMFS, VMware
pushes VMFS as a high performance file system so I
would say that VMFS is faster. You cannot run DRS or
HA on NFS, you can use VMotion.
Have you tried to setup HA/DRS with NFS datastores?
Iwould think it would work since vmotion can be used.
The resource management guide says they require shared SAN storage.
I think NFS volumes on a SAN would qualify.
Hi seangar,
my colleague ask me the same since the start of our vmware environment (Feb 2007).
Since we are all TCP/IP Ethernet guys and no native Storage Men exists, we're using NFS for most of our things and iSCSI for vmware (Since VMWare always told the NFS is not a good choice). But NFS for VM's would make our lives easier.
Snap Shot, Storage over subscription and VMWare use thin disk as default. We mostly running small linux server inside the VM's and would benfit from not reservating to much diskspace.
So maybe you can tell me your decision about NFS vs iSCSI and your exprience.
Markus