Ceph: restore cluster after loosing all ceph-mon's
Ceph: restore cluster after losing all ceph-mon's
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Here we will describe how to restore a Ceph cluster after a disaster where all ceph-mon's are lost. Of course we assume that the data on the OSD devices are preserved!
Here we will describe how to restore a Ceph cluster after a disaster where all ceph-mon's are lost. We obviously assume that the data on the OSD devices are preserved!
The procedure refers to a Ceph cluster created with Juju.
The procedure refers to a Ceph cluster created with Juju.
Suppose that you have lost (or removed by mistake) all ceph-mon's. We start recreating them, i.e. we have three new ceph-mon units.
Suppose that you have lost (or removed by mistake) all ceph-mon's. We start recreating them, i.e. we have three new ceph-mon units, unfortunately the new mon's do not know anything of the OSD's.
Stop all OSDs
Stop all OSDs
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@@ -32,6 +32,7 @@ Rebuild OSD mon map
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@@ -32,6 +32,7 @@ Rebuild OSD mon map
On the juju client machine, rebuild old mon map using existing OSDs with the following script, which will save result to ./mon-store::
On the juju client machine, rebuild old mon map using existing OSDs with the following script, which will save result to ./mon-store::