Best storage solution

[gamenetwork]

_{Hi guys,}

let me make this simple.

nfs or iscsi?
and is a 2 1Gbit ethernet connectors enough.

Im hoping that i can setup a system with 3 nodes with HA on.

I have looking at to nas servers from synology:
DS1512+ http://www.synology.com/products/product.php?product_name=DS1512+&lang=enu
rs812 http://www.synology.com/products/product.php?product_name=RS812&lang=enu

thanks in advance.

 

[RobFantini]

are you going to use zfs?

 

[mir]

_{Hi guys,}

let me make this simple.

nfs or iscsi?
and is a 2 1Gbit ethernet connectors enough.

As can be read in this paper: http://lass.cs.umass.edu/papers/pdf/FAST04.pdf
It seems that iSCSI out performs NFS when in comes to write intensive use - like a virtual server setup. Another benefit is that the CPU utilization is more than doubled for NFS compared to iSCSI.

The question to bandwidth: If your disks are SATA II 7200 RPM and you are using RAID 10 or RAID 5(6) gigabit will be sufficient. Eg. network will not be the bottle neck. If you are using SAS 15000 RPM or SSD disks and gigabit then the network will be the bottle neck. So if you are preparing a very I/O intensive setup like a high performance database cluster you should consider 10 gigabit or use 2 or more gigabit nics in a bonding setup on each PVE node .

 

[gamenetwork]

As can be read in this paper: http://lass.cs.umass.edu/papers/pdf/FAST04.pdf
It seems that iSCSI out performs NFS when in comes to write intensive use - like a virtual server setup. Another benefit is that the CPU utilization is more than doubled for NFS compared to iSCSI.

The question to bandwidth: If your disks are SATA II 7200 RPM and you are using RAID 10 or RAID 5(6) gigabit will be sufficient. Eg. network will not be the bottle neck. If you are using SAS 15000 RPM or SSD disks and gigabit then the network will be the bottle neck. So if you are preparing a very I/O intensive setup like a high performance database cluster you should consider 10 gigabit or use 2 or more gigabit nics in a bonding setup on each PVE node .

Well the paper explains that iscsi is the way to go.
and im going for the SATA II 7200 RPM.

so thats solved thanks again.

now the question is, shall i use "disk cache" on the vm's ?

 

[e100]

now the question is, shall i use "disk cache" on the vm's ?

My experience is that "no cache" performs best.
Reason is there is less data copies and bus traffic.
http://www.linux-kvm.org/page/Tuning_KVM

 

[gamenetwork]

My experience is that "no cache" performs best.
Reason is there is less data copies and bus traffic.
http://www.linux-kvm.org/page/Tuning_KVM

Thanks for the help.

 

[RobFantini]

If you will use zfs, see post #7 at http://forum.proxmox.com/threads/8490-Native-ZFS-for-Linux-on-Proxmox :
"To run KVM on ZFS you have to change cache to: Write back "