Automatic worker node preparation
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Astra Trident can automatically install the required
iSCSI tools on the nodes present in the Kubernetes cluster. This is a beta feature and is not meant for production clusters. Today, the feature is available for nodes that run CentOS, RHEL, and Ubuntu.
For this feature, Astra Trident includes a new install flag:
--enable-node-prep for installations deployed with
tridentctl. For deployments with the Trident operator, use the Boolean option
--enable-node-prep flag is included for Astra Trident installations deployed with
tridentctl, here is what happens:
As part of the installation, Astra Trident registers the nodes it runs on.
When a Persistent Volume Claim (PVC) request is made, Astra Trident creates a PV from one of the backends it manages.
Using the PVC in a pod would require Astra Trident to mount the volume on the node the pod runs on. Astra Trident attempts to install the required NFS/iSCSI client utilities and to ensure that the required services are active. This is done before the volume is mounted.
The preparation of a worker node is done only once as part of the first attempt made to mount a volume. All subsequent volume mounts should succeed as long as no changes outside Astra Trident touch the
In this manner, Astra Trident can ensure that all the nodes in a Kubernetes cluster have the required utilities needed to mount and attach volumes. For NFS volumes, the export policy should also permit the volume to be mounted. Trident can automatically manage export policies per backend; alternatively, users can manage export policies out-of-band.