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1.) Add them to the cluster but do not consider them while deploying the VM and if host is upgraded to have this capability, we should make necessary changes to consider it for deploying VMsDon't allow adding a host which has no capability of overcommiting resources to a cluster.
2.) Disable overcommit feature in clusters which have hosts not capable of overcommiting the resourcesAdd the host but do not consider it for vm allocation until it is updated.
1.) Disable the overcommit feature in clusters existing before the upgrade. The admin should manually enable it, cloudstack will check the all the host for the overcommit capability and do the necessary.
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