Emir Mapping iSCSI volumes to one of the physical servers (KVM host) and then exporting filesystem via NFS will be a good option in your case. This essentially makes one of the hosts to be the NFS server, but you can still use it as KVM host in VCL. If you have enough local storage on each server you can configure VCL to store running images on local storage - this will improve performance, since NFS will be used mostly as read-only, except when you update an image. And if you trust your network use 'udp' mount option on NFS client, which will make it even faster.
Thanks. On Jul 11, 2013, at 14:16 , Emir Imamagic <[email protected]> wrote: > Hello, > > we are currently running VCL on top of VMware ESXi 4.1 and are planning to > migrate to KVM. Main reason is that 4.1 does not support some of newer OS-es > (e.g. Win 8) and ESXi 5 memory limitations are too restrictive for our > servers. > > Currently we have 4 VMware ESXi servers which are using iSCSI storage for > both datastore and vmstore. For datastore we benefit from the fact that > VMware VMFS is inherently clustered, i.e. i is able to mount same LUN from > multiple servers. > > In case of KVM we obviously need to use something else, either NFS or one of > the server-less systems (e.g. GFS or OCFS). Our storage system does not > provide NFS interface so we would need to set up NFS servers. This solution > introduces another component (and cost) in system and we would like to avoid > it. With GFS we had some performance issues in the past, and OCFS we haven't > tested yet. We also considered using something more exotic like MooseFS, > Gluster or CEPH, however for all of them we need to buy more servers, which > is currently not an option. > > I would like to kindly ask other KVM-based VCL instances to share their > experiences, what do you use for datastore? > > Thanks in advance > -- > Emir Imamagic > SRCE - University of Zagreb University Computing Centre, www.srce.unizg.hr > [email protected], tel: +385 1 616 5809, fax: +385 1 616 5559 > -- Thank you, Dmitri Chebotarov VCL Sys Eng, Engineering & Architectural Support, TSD - Ent Servers & Messaging 223 Aquia Building, Ffx, MSN: 1B5 Phone: (703) 993-6175 | Fax: (703) 993-3404
