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[Moritz Krinke <mkrinke@xxxxxxxxxxxxxxxxx>]

Hello,

beeing new to openstack in general and more specific to swift i've set up a
folsom 2node cluster in vms, using ubuntu cloud archive packages on ubuntu
12.04.

My goal is to have a 2node cluster where each node acts both as a storage
node and a proxy node.
Each node will have 12*2TB drives

Now i already have one of those nodes and there are ~ 16TB of data on it.
This data i would like to migrate into swift using 2 replicas for it.

Initially i thought i could just bring up the second node, migrate the data
into it only using one replicata at migratation time, install swift on the
old node and change to two replicas.

Unfortunately after reading the documentation this does not seem to be
possible.
- I cannot change the number of replicas after creating the ring (e.g.
changing it from 1 to 2)
- I could put each drive in its one zone, but this would create two copies
of each file/object on the first node while migrating. I do not have enough
empty space on that node.

Now my questions are:
- are my previous assumptions correct?
- reading about the "unique-as-possible" feature in folsom im asking myself
how would swift know if nodes are in different places, is there a feature
like "regions" i am not aware of?
- after migration of data and having two replicas spread over those two
nodes, how can i make sure that in the event of a node beeing down swift
will not start copying files to second drives on the healty nodes?


Thanks a lot,
Moritz