Hi, > 2) does ceph support FC or how can i get FC supported in ceph? like we use > iscsi target tool to export rbd block device ,so windows can use it as a > disk. LIO Linux SCSI Target has option to export block device via FC among other options. I guess you can use that to access ceph via FC. http://linux-iscsi.org/wiki/Target Ugis 2013/7/5 Gregory Farnum <greg@xxxxxxxxxxx>: > On Thu, Jul 4, 2013 at 7:09 PM, huangjun <hjwsm1989@xxxxxxxxx> wrote: >> hi,all >> there are some questions about ceph. >> 1) can i get the osd list that hold objects consist of a file by >> command-line? > > If using CephFS you can use the cephfs tool to map offsets to > locations. Is that what you mean? > >> 2) does ceph support FC or how can i get FC supported in ceph? like we use >> iscsi target tool to export rbd block device ,so windows can use it as a >> disk. > > Hmm, don't think so yet. Does that concept even make sense for fibre > channel connections? > >> 3) the question i thought many times, the crush hierarchy is >> stack,host,device,and the replication level is 2, but if two disks failed in >> different stack in 5 mins, how can i cut down the risk of data lose to >> lowest? I thought about disaster backup by building a remote datacenter, >> but if another two disks also failed in that datacenter? > > The possibility of data loss due to simultaneous disk failures is > pretty much a constant (though fairly unlikely!). If two disks doesn't > provide the redundancy you need, you can use three. Separating the > failure domains as much as possible of course helps reduce the odds > more. > >> 4) "df -h" on client shows the data stored(include the replicated data) in >> cluster, not data really used by user. > > Yep. Keeping in mind that due to using different replication settings > etc we can't map the total space to a user-visible space, what would > you rather see here? > -Greg > Software Engineer #42 @ http://inktank.com | http://ceph.com > _______________________________________________ > ceph-users mailing list > ceph-users@xxxxxxxxxxxxxx > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
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