Cluster Evaluation

How kspider Works

Figure 1 shows the architecture of kspider, which consists of three modules: collection, connection management, and analysis. The collection module can collect data of the source cluster, including namespaces, workloads, nodes, and networks. The connection management module establishes connections with the API Server of the source cluster. The analysis module aims to output the collected data of the source cluster (generating the cluster-*.json file) and provide the recommendation information of the destination cluster (generating the preferred-*.json file) after evaluation.

Figure 1 kspider architecture

Usage of kspider

kspider can run on Linux (x86 and Arm) and Windows. The usage is similar in both environments. This section uses the Linux (x86) environment as an example.

If Linux (Arm) or Windows is used, replace kspider-linux-amd64 in the following command with kspider-linux-arm64 or kspider-windows-amd64.exe.

Prepare a server, upload kspider to the server, and decompress the tool package. For details, see Preparations. Run ./kspider-linux-amd64 -h in the directory where kspider is located to learn about its usage.

• -k, --kubeconfig: specifies the location of the kubeconfig file of kubectl. The default value is $HOME/.kube/config. The kubeconfig file is used to configure access to the Kubernetes cluster. The kubeconfig file contains the authentication credentials and endpoints (access addresses) required for accessing and registering the Kubernetes cluster. For details, see the Kubernetes documentation.
• -n, --namespaces: specifies the collected namespace. By default, system namespaces such as kube-system, kube-public, and kube-node-lease are excluded.
• -q, --quiet: indicates static exit.
• -s, --serial: specifies the unique sequence number of the output aggregation file (cluster-{serial}.json) and recommendation file (preferred-{serial}.json).

$ ./kspider-linux-amd64 -h
A cluster information collection and recommendation tool implement by Go.

Usage:
  kspider [flags]

Aliases:
  kspider, kspider

Flags:
  -h, --help                help for kspider
  -k, --kubeconfig string   The kubeconfig of k8s cluster's. Default is the $HOME/.kube/config. (default "$HOME/.kube/config")
  -n, --namespaces string   Specify a namespace for information collection. If multiple namespaces are specified, separate them with commas (,), such as ns1,ns2. default("") is all namespaces
  -q, --quiet               command to execute silently
  -s, --serial string       User-defined sequence number of the execution. The default value is the time when the kspider is started. (default "1673853404")

Step 1: Collect Data from the Source Cluster

1. Connect to the source cluster using kubectl. For details, see Connecting to a Cluster Using kubectl.
2. Use the default parameter settings to collect data of all namespaces in the cluster. Run the ./kspider-linux-amd64 command.
   Command output:

   [~]# ./kspider-linux-amd64
   The Cluster version is v1.15.6-r1-CCE2.0.30.B001
   There are 5 Namespaces
   There are 2 Nodes
   	Name	 CPU	 Memory	 IP	 Arch	 OS	 Kernel	 MachineID
   	10.1.18.64	 4	 8008284Ki	 [10.1.18.64 10.1.18.64]	 amd64	 linux	 3.10.0-1127.19.1.el7.x86_64	 ef9270ed-7eb3-4ce6-a2d8-f1450f85489a
   	10.1.19.13	 4	 8008284Ki	 [10.1.19.13 10.1.19.13]	 amd64	 linux	 3.10.0-1127.19.1.el7.x86_64	 2d889590-9a32-47e5-b947-09c5bda81849
   There are 9 Pods
   There are 0 LonePods: 
   There are 2 StatefulSets: 
   	Name	 Namespace	 NodeAffinity
   	minio	 default	 false
   	minio	 minio	 false
   There are 3 Deployments: 
   	Name	 Namespace	 NodeAffinity
   	rctest	 default	 true
   	flink-operator-controller-manager	 flink-operator-system	 false
   	rctest	 minio	 false
   There are 1 DaemonSets: 
   	Name	 Namespace	 NodeAffinity
   	ds-nginx	 minio	 false
   There are 0 Jobs: 
   There are 0 CronJobs: 
   There are 4 PersistentVolumeClaims: 
   	Namespace/Name	 Pods
   	default/pvc-data-minio-0	 default/minio-0
   	minio/obs-testing	 minio/ds-nginx-9hmds,minio/ds-nginx-4jsfg
   	minio/pvc-data-minio-0	 minio/minio-0
   There are 5 PersistentVolumes: 
   	Name	 Namespace	 pvcName	 scName	 size	 key
   	pvc-bd36c70f-75bf-4000-b85c-f9fb169a14a8	 minio-pv	 obs-testing	 csi-obs	 1Gi	 pvc-bd36c70f-75bf-4000-b85c-f9fb169a14a8
   	pvc-c7c768aa-373a-4c52-abea-e8b486d23b47	 minio-pv	 pvc-data-minio-0	 csi-disk-sata	 10Gi	 1bcf3d00-a524-45b1-a773-7efbca58f36a
   	pvc-4f52462b-3b4c-4191-a63b-5a36a8748c05	 minio	 obs-testing	 csi-obs	 1Gi	 pvc-4f52462b-3b4c-4191-a63b-5a36a8748c05
   	pvc-9fd92c99-805a-4e65-9f22-e238130983c8	 default	 pvc-data-minio-0	 csi-disk	 10Gi	 590afd05-fc68-4c10-a598-877100ca7b3f
   	pvc-a22fd877-f98d-4c3d-a04e-191d79883f97	 minio	 pvc-data-minio-0	 csi-disk-sata	 10Gi	 48874130-df77-451b-9b43-d435ac5a11d5
   There are 7 Services: 
   	Name	 Namespace	 ServiceType
   	headless-lxprus	 default	 ClusterIP
   	kubernetes	 default	 ClusterIP
   	minio	 default	 NodePort
   	flink-operator-controller-manager-metrics-service	 flink-operator-system	 ClusterIP
   	flink-operator-webhook-service	 flink-operator-system	 ClusterIP
   	headless-lxprus	 minio	 ClusterIP
   	minio	 minio	 NodePort
   There are 0 Ingresses: 
   There are 6 Images: 
   	Name
   	gcr.io/flink-operator/flink-operator:v1beta1-6
   	flink:1.8.2
   	swr.cn-north-4.myhuaweicloud.com/paas/minio:latest
   	nginx:stable-alpine-perl
   	swr.cn-north-4.myhuaweicloud.com/everest/minio:latest
   	gcr.io/kubebuilder/kube-rbac-proxy:v0.4.0
   There are 2 Extra Secrets: 
   	SecretType
   	cfe/secure-opaque
   	helm.sh/release.v1

   After the kspider command is executed, the following files are generated in the current directory:

   • cluster-*.json: This file contains data collected from the source cluster and applications. The data can be used to analyze and plan the migration.
   • preferred-*.json: This file contains information about the recommended destination cluster. A preliminary evaluation is performed for the source cluster according to its scale and node specifications. The file provides suggestions on the version and scale of the destination cluster.

3. View the data collected from the source cluster and applications.

   You can use a text editor or JSON viewer to open the cluster-*.json file to view the data. Replace the asterisk (*) in the file name with the actual timestamp or serial number to find and open the correct file.

   Description of the cluster-*.json file:

   {
     K8sVersion: Kubernetes version. The value is a string.
     Namespaces: number of namespaces. The value is a string.
     Pods: total number of pods. The value is an integer.
     Nodes: node information. The IP address is used as the key to display node information.
       IP addresses
         CPU: CPU. The value is a string.
         Arch: CPU architecture. The value is a string.
         Memory: memory. The value is a string.
         HugePages1Gi: 1 GB hugepage memory. The value is a string.
         HugePages2Mi: 2 MB hugepage memory. The value is a string.
         OS: node OS. The value is a string.
         KernelVersion: OS kernel version. The value is a string.
         RuntimeVersion: running status and version of the node container. The value is a string.
         InternalIP: internal IP address. The value is a string.
         ExternalIP: external IP address. The value is a string.
         MachineID: node ID. The value is a string. Ensure that the CCE ID is the same as the ECS ID.
     Workloads: workload
       Deployment: workload type. The value can be Deployment, StatefulSet, DaemonSet, CronJob, Job, or LonePod.
         default: namespace name
           Count: quantity. The value is an integer.
           Items: details. The value is an array.
             Name: workload name. The value is a string.
             Namespace: namespace name. The value is a string.
             NodeAffinity: node affinity. The value is of the Boolean type.
             Replicas: number of replicas. The value is an integer.
     Storage: storage
       PersistentVolumes: persistent volume
         pv-name: The PV name is used as the key.
           VolumeID: volume ID. The value is a string.
           Namespace: namespace. The value is a string.
           PvcName: name of the bound PVC. The value is a string.
           ScName: storage class name. The value is a string.
           Size: size of the space to request. The value is a string.
           Pods: name of the pod that uses the PV. The value is a string.
           NodeIP: IP address of the node where the pod is located. The value is a string.
           VolumePath: path of the node to which the pod is mounted. The value is a string.
       OtherVolumes: volumes of other types
         Type: AzureFile, AzureDisk, GCEPersistentDisk, AWSElasticBlockStore, Cinder, Glusterfs, NFS, CephFS, FlexVolume, FlexVolume, DownwardAPI
           The volume ID, volume name, and volume shared path are keys.
           Pods: name of the pod. The value is a string.
             NodeIP: IP address of the node where the pod is located. The value is a string.
             Information that uniquely identifies a volume, such as the volume ID, volume name, and volume shared path. The value is a string.
     Networks: network
       LoadBalancer: load balancing type
         service: network type, which can be Service or Ingress.
           Name: name. The value is a string.
           Namespace: namespace name. The value is a string.
           Type: type. The value is a string.
     ExtraSecrets: extended secret type
       Secret type. The value is a string.
     Images: image
       Image repo. The value is a string.
   }

   Example:

   {
     "K8sVersion": "v1.19.10-r0-CCE22.3.1.B009",
     "Namespaces": 12,
     "Pods": 33,
     "Nodes": {
       "10.1.17.219": {
         "CPU": "4",
         "Memory": "7622944Ki",
         "HugePages1Gi": "0",
         "HugePages2Mi": "0",
         "Arch": "amd64",
         "OS": "EulerOS 2.0 (SP9x86_64)",
         "KernelVersion": "4.18.0-147.5.1.6.h687.eulerosv2r9.x86_64",
         "RuntimeVersion": "docker://18.9.0",
         "InternalIP": "10.1.17.219",
         "ExternalIP": "",
         "MachineID": "0c745e03-2802-44c2-8977-0a9fd081a5ba"
       },
       "10.1.18.182": {
         "CPU": "4",
         "Memory": "7992628Ki",
         "HugePages1Gi": "0",
         "HugePages2Mi": "0",
         "Arch": "amd64",
         "OS": "EulerOS 2.0 (SP5)",
         "KernelVersion": "3.10.0-862.14.1.5.h520.eulerosv2r7.x86_64",
         "RuntimeVersion": "docker://18.9.0",
         "InternalIP": "10.1.18.182",
         "ExternalIP": "100.85.xxx.xxx",
         "MachineID": "2bff3d15-b565-496a-817c-063a37eaf1bf"
       }
     },
     "Workloads": {
       "CronJob": {},
       "DaemonSet": {
         "default": {
           "Count": 1,
           "Items": [
             {
               "Name": "kubecost-prometheus-node-exporter",
               "Namespace": "default",
               "NodeAffinity": false,
               "Replicas": 3
             }
           ]
         }
       },
       "Deployment": {
         "default": {
           "Count": 1,
           "Items": [
             {
               "Name": "kubecost-cost-analyzer",
               "Namespace": "default",
               "NodeAffinity": false,
               "Replicas": 1
             }
           ]
         },
         "kubecost": {
           "Count": 1,
           "Items": [
             {
               "Name": "kubecost-kube-state-metrics",
               "Namespace": "kubecost",
               "NodeAffinity": false,
               "Replicas": 1
             }
           ]
         }
       },
       "Job": {},
       "LonePod": {},
       "StatefulSet": {
         "minio-all": {
           "Count": 1,
           "Items": [
             {
               "Name": "minio",
               "Namespace": "minio-all",
               "NodeAffinity": false,
               "Replicas": 1
             }
           ]
         }
       }
     },
     "Storage": {
       "PersistentVolumes": {
         "demo": {
           "VolumeID": "demo",
           "Namespace": "fluid-demo-test",
           "PvcName": "demo",
           "ScName": "fluid",
           "Size": "100Gi",
           "Pods": "",
           "NodeIP": "",
           "VolumePath": ""
         },
         "pvc-fd3a5bb3-119a-44fb-b02e-96b2cf9bb36c": {
           "VolumeID": "82365752-89b6-4609-9df0-007d964b7fe4",
           "Namespace": "minio-all",
           "PvcName": "pvc-data-minio-0",
           "ScName": "csi-disk",
           "Size": "10Gi",
           "Pods": "minio-all/minio-0",
           "NodeIP": "10.1.23.159",
           "VolumePath": "/var/lib/kubelet/pods/5fc47c82-7cbd-4643-98cd-cea41de28ff2/volumes/kubernetes.io~csi/pvc-fd3a5bb3-119a-44fb-b02e-96b2cf9bb36c/mount"
         }
       },
       "OtherVolumes": {}
     },
     "Networks": {
       "LoadBalancer": {}
     },
     "ExtraSecrets": [
       "cfe/secure-opaque",
       "helm.sh/release.v1"
     ],
     "Images": [
       "nginx:stable-alpine-perl",
       "ghcr.io/koordinator-sh/koord-manager:0.6.2",
       "swr.cn-north-4.myhuaweicloud.com/paas/minio:latest",
       "swr.cn-north-4.myhuaweicloud.com/everest/e-backup-test:v1.0.0",
       "gcr.io/kubecost1/cost-model:prod-1.91.0",
       "gcr.io/kubecost1/frontend:prod-1.91.0"
     ]
   }

Step 2: Evaluate the Destination Cluster

After the kspider command is executed, in addition to the cluster-*.json file, the preferred-*.json file is also generated in the current directory. After performing preliminary evaluation for the source cluster according to its scale and node specifications, the file provides the recommended version and scale of the destination cluster. This helps you better plan and prepare for the migration.

Description of the preferred-*.json file:

{
  K8sVersion: Kubernetes version. The value is a string.
  Scale: cluster scale. The value is a string.
  Nodes: node information
    CPU: CPU. The value is a string.
    Memory: memory. The value is a string.
    Arch: CPU architecture. The value is a string.
    KernelVersion: OS kernel version. The value is a string.
    ProxyMode: cluster proxy mode. The value is a string.
  ELB: whether the ELB service is a dependent service. The value is of the Boolean type.
}

Evaluation rules for each field in the preceding file:

Example:

{
  "K8sVersion": "v1.21",
  "Scale": 50,
  "Nodes": {
    "CPU": "4",
    "Memory": "7622952Ki",
    "Arch": "amd64",
    "KernelVersion": "3.10.0-862.14.1.5.h520.eulerosv2r7.x86_64"
  },
  "ELB": false,
  "ProxyMode": "iptables"
}

The evaluation result is for reference only. You need to determine the version and scale of the destination cluster.