>From the docs for each project:

"When a primary storage outage occurs the hypervisor immediately stops
all VMs stored on that storage
device"http://docs.cloudstack.apache.org/projects/cloudstack-administration/en/4.8/reliability.html

"CloudStack will only bind to one monitor (You can however create a
Round Robin DNS record over multiple
monitors)"http://docs.ceph.com/docs/master/rbd/rbd-cloudstack/

Doesn't this mean that if the CEPH monitor cloudstack chooses to bind to
goes down all your VMs stop? If so, that seems pretty risky.

RRDNS is for poor man's load balancing, not HA. I guess it depends on when
Cloudstack does DNS lookup and if there's some minimum unavailable delay
before it flags primary storage as offline, but it seems like substituting
RRDNS for whatever CEPH's internal "find an available monitor" algorithm is
is a bad idea.

-- 
Adam Carheden
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