Hi,
I read that iscsi is used by many people with esx server and the performance is not so bad with "real" life.
I would like to know why not consider nfs for production environment.
Here my thoughts :
With iSCSI
- ESX must serialize every IO on a VMFS lun.
- Iscsi can use only one Ethernet link at a time. So the limit is 1 Gb/s
With NFS
- ESX can access to all VM concurently
- One can use a VIF (agregate of Ethernet to get more than 1Gb/s)
-Backup a VM is like backuping files. Very easy with NetApp snaphots for instance.
- Snapmirror of VM on a DR site.
So my interrogations are on perfs issue ?
Does anyone have tested NFS on production environnement ? How many VM ?
Thanks
ML
I have just started using ASIS on a VMware ISCSI volume. We do thin provisioning as well on the NAS. Here is a link to a blog that I put up and will be updating
http://blog.colovirt.com/2008/10/23/netapp-deduplication-a-sis-and-vmware/
Asis has been running on the volume for a few days and there are only 9 virtual machines there. I will be moving over a lot more in the next few weeks. The current compression is as follows:
Filesystem used saved %saved
/vol/vmware/ 96GB 99GB 51%
kevin@colovirt.com
Got an update. Getting better deduplication. Still moving over development and non critical VMs to the sis volume. This is an ISCSI LUN formatted VMFS.
NAS> df -sh /vol/testVol
Filesystem | used | saved | %saved |
/vol/testVol/ | 519GB | 754GB | 59% |
Saving 749 gig so far! ASIS (NetApp dedipe) setup information can be found here:
If you use iSCSI with hardware initiators you can manually load balance to use 2 links at once on the ESX side.
ESX runs great on blades. You just need the right blades. I'd love to hear arguments to the contrary.