everest (System Resource Add-on, Mandatory)¶
Introduction¶
everest is a cloud native container storage system, which enables clusters of Kubernetes v1.15.6 or later to access cloud storage services through the Container Storage Interface.
everest is a system resource add-on. It is installed by default when a cluster of Kubernetes v1.15 or later is created.
Constraints¶
If your cluster is upgraded from v1.13 to v1.15, storage-driver is replaced by everest (v1.1.6 or later) for container storage. The takeover does not affect the original storage functions.
In version 1.2.0 of the everest add-on, key authentication is optimized when OBS is used. After the everest add-on is upgraded from a version earlier than 1.2.0, restart all workloads that use OBS in the cluster. Otherwise, workloads may not be able to use OBS.
By default, this add-on is installed in clusters of v1.15 and later. For clusters of v1.13 and earlier, the storage-driver add-on is installed by default.
Installing the Add-on¶
This add-on has been installed by default. If it is uninstalled due to some reasons, you can reinstall it by performing the following steps:
Log in to the CCE console and click the cluster name to access the cluster console. Choose Add-ons in the navigation pane, locate everest on the right, and click Install.
On the Install Add-on page, configure the specifications.
Table 1 Add-on configuration¶ Parameter
Description
Add-on Specifications
Select Single, Custom, or HA for Add-on Specifications.
Pods
Number of pods that will be created to match the selected add-on specifications.
If you select Custom, you can adjust the number of pods as required.
Multi-AZ
Preferred: Deployment pods of the add-on will be preferentially scheduled to nodes in different AZs. If all the nodes in the cluster are deployed in the same AZ, the pods will be scheduled to that AZ.
Required: Deployment pods of the add-on will be forcibly scheduled to nodes in different AZs. If there are fewer AZs than pods, the extra pods will fail to run.
Containers
The everest add-on contains the everest-csi-controller and everest-csi-driver components. For details, see Components.
If you select Custom, you can adjust the component specifications as required. The CPU and memory request values can be increased based on the number of nodes and PVCs. For details, see Table 2.
In non-typical scenarios, the formulas for estimating the limit values are as follows:
everest-csi-controller
CPU limit: 250m for 200 or fewer nodes, 350m for 1000 nodes, and 500m for 2000 nodes
Memory limit = (200 MiB + Number of nodes x 1 MiB + Number of PVCs x 0.2 MiB) x 1.2
everest-csi-driver
CPU limit: 300 m for 200 or fewer nodes, 500 m for 1000 nodes, and 800 m for 2000 nodes
Memory limit: 300 MiB for 200 or fewer nodes, 600 MiB for 1000 nodes, and 900 MiB for 2000 nodes
Table 2 Recommended configuration limits in typical scenarios¶ Configuration Scenario
everest-csi-controller
everest-csi-driver
Nodes
PVs/PVCs
Add-on Instances
CPU (The limit value is the same as the requested value.)
Memory (The limit value is the same as the requested value.)
CPU (The limit value is the same as the requested value.)
Memory (The limit value is the same as the requested value.)
50
1000
2
250 m
600 MiB
300 m
300 MiB
200
1000
2
250 m
1 GiB
300 m
300 MiB
1000
1000
2
350 m
2 GiB
500 m
600 MiB
1000
5000
2
450 m
3 GiB
500 m
600 MiB
2000
5000
2
550 m
4 GiB
800 m
900 MiB
2000
10,000
2
650 m
5 GiB
800 m
900 MiB
Configure the add-on parameters.
Table 3 Add-on parameters¶ Parameter
Description
csi_attacher_worker_threads
Number of worker nodes that can concurrently attach EVS volumes. The default value is 60.
csi_attacher_detach_worker_threads
Number of worker nodes that can concurrently detach EVS volumes. The default value is 60.
volume_attaching_flow_ctrl
Maximum number of EVS volumes that can be attached by the everest add-on within 1 minute. The default value is 0, indicating that the performance of attaching EVS volumes is determined by the underlying storage resources.
cluster_id
Cluster ID
default_vpc_id
ID of the VPC to which the cluster belongs
disable_auto_mount_secret
Whether the default AK/SK can be used when an object bucket or parallel file system is mounted. The default value is false.
enable_node_attacher
Whether to enable the attacher on the agent to process the VolumeAttachment.
flow_control
This field is left blank by default. You do not need to configure this parameter.
over_subscription
Overcommitment ratio of the local storage pool (local_storage). The default value is 80. If the size of the local storage pool is 100 GB, it can be overcommitted to 180 GB.
project_id
ID of the project to which a cluster belongs
Note
In everest 1.2.26 or later, the performance of attaching a large number of EVS volumes has been optimized. The following parameters can be configured:
csi_attacher_worker_threads
csi_attacher_detach_worker_threads
volume_attaching_flow_ctrl
The preceding parameters are associated with each other and are constrained by the underlying storage resources in the region where the cluster is located. To attach a large number of volumes (more than 500 EVS volumes per minute), contact customer service and configure the parameters under their guidance to prevent the everest add-on from running abnormally due to improper parameter settings.
Click Install.
Components¶
Container Component | Description | Resource Type |
|---|---|---|
everest-csi-controller | Used to create, delete, snapshot, expand, attach, and detach storage volumes. If the cluster version is 1.19 or later and the add-on version is 1.2.x, the pod of the everest-csi-controller component also has an everest-localvolume-manager container by default. This container manages the creation of LVM storage pools and local PVs on the node. | Deployment |
everest-csi-driver | Used to mount and unmount PVs and resize file systems. If the add-on version is 1.2.x and the region where the cluster is located supports node-attacher, the pod of the everest-csi-driver component also contains an everest-node-attacher container. This container is responsible for distributed EVS attaching. This configuration item is available in some regions. | DaemonSet |