mirror of https://github.com/schoebel/mars
34 lines
1.2 KiB
Plaintext
34 lines
1.2 KiB
Plaintext
This CONTRIB directory contains some unsupported _example_ bash scripts
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for MARS background data migration.
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Method:
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0) start point: all resources have two replicas, each on a pair of
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nodes. "marsadm view all" shows this as [2/2], meaning two replicas
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out of two potential replication hosts.
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1) use "marsadm join-cluster" for merging two ordinary replication pairs
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into a 4-fold (quadruple) MARS cluster. Now we have [2/4].
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2) create two additional resource replicas via "marsadm join-resource".
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The new replicas are created in background while the data is being updated
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during ordinary production.
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Finally we have [4/4] replicas.
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3) handover the primary to one node of the _new_ pair.
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4) use "marsadm leave-resource" to get rid of the _old_ two replicas.
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New replica status is again [2/4], but the the replicas have been
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migrated to the new pair in the meantime.
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5) Finally, use "marsadm split-cluster" to go back to [2/2].
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HINT:
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The shell script code is split into two parts: a generic part which
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should be usable at more MARS sites in the world, and a 1&1 specific
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part which will only work in the 1&1 Shared Hosting Linux environment.
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However, by looking at the code, you should be able to create your own
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adaptations.
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