Is a setting for change the behavior to return read error instead of block read?
I think it is more reasonable behavior because it is similar to bad block on HDD: it can’t be read. Or may be a timeout some seconds, then return read error for the block and other absented blocks in same image/PG. Or is any method safe upgrade cluster without downtime. Now if I will upgrade monitors and upgrade will fail on second (of three) monitor - cluster will down. Becouse it will have 1 new monitor 1 down monitor 1 old monitor Old and mew monitor haven’t quorum. Same for 5 monitors: 2 new monitors 1 down monitor 2 old monitors. > On 04/28/2014 02:35 PM, Timofey Koolin wrote: >> What will happened if RBD lose all copied of data-block and I read the block? >> > > The read to the object will block until a replica comes online to serve it. > > Remember this with Ceph: "Consistency goes over availability" > >> Context: >> I want use RDB as main storage with replication factor 1 and drbd for >> replication on non rbd storage by client side. >> >> For example: >> Computer1: >> 1. connect rbd as /dev/rbd15 >> 2. use rbd as disk for drbd >> >> Computer2: >> Use HDD for drbd-replication. >> >> >> I want protect from break of ceph system (for example while upgrade ceph) >> and long-distance replication. > > Ceph wants to be consistent at all times. So copying over long distances with > high latency will be very slow. > >> >> >> _______________________________________________ >> ceph-users mailing list >> [email protected] >> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com >> > > > -- > Wido den Hollander > 42on B.V. > Ceph trainer and consultant > > Phone: +31 (0)20 700 9902 > Skype: contact42on > _______________________________________________ > ceph-users mailing list > [email protected] > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com _______________________________________________ ceph-users mailing list [email protected] http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
