I have an image server, this server contains disk images to be used by virtual machines.
The server has to allow the runtime creation of new images, so iscsi is not good as it requires to restart the iscsi server in order to introduce a new target and I don’t want that (I could’t find any api to edit the /etc/iet/ietd.conf file either so it would be tricky too).
For this reason I am looking at nfs: I would mount this remote folder on each host and a new vm disk creation by the image server is supported as, from nfs point of view, it is equivalent to add a new file into the shared folder.
On a lan it works fine, but now that I have to extend my system to the internet I have these two doubts:
1- do nfs support a folder sharing over the internet? It seems to have been developed for LANs so I don’t know how it deals with NATs, firewalls and stuff.
2- do nfs offer good performances? These vm images have to be used by virtual machines, so communication has to be pretty responsive.
If these two points are not satisfied can you also suggest me a good alternative?
NFS can run over the Internet, but not well. It’s simply not optimized for the sub-par WAN links and possible traffic loss associated with it.
I agree with Andrew B on this one. There’s usually at least a server on the same LAN segment for handling images in a given location. NFS is far too unreliable (any WAN-based system is) to be used for an active operating system image. You’d probably see a lot of corrupt copies if you tried it.