I was wondering what people use / recommend for a cluster fs for use with xen ?

Also with this cluster fs, will the domU's be using flat files / lvm ? (it should be the former as per my guess since these flat files will be stored on the cluster fs, but then won't performance hit will be there for these domU's ? )

I don't want to invest in a san/ nas solution, just looking for cost effective. Right now i have a single server which i will use for the cluster fs and slowly add more servers to the cluster as and when i need more space. Atleast thats what i have thought till now.

All ideas are welcome.

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regards,

Anand Gupta