七张图入门 Hadoop 在 K8S 环境中部署-hadoop on k8s

一、概述

为核心的 Hadoop 为用户提供了系统底层细节透明的分布式基础架构。hdfs 的高容错性、高伸缩性、高效性等优点让用户可以将 Hadoop 部署在低廉的硬件上，形成分布式系统。目前最新版本已经是 3.x 了，官方文档：https://hadoop.apache.org/docs/current/index.html

HDFS

YARN

二、开始部署

1）添加源

地址：https://artifacthub.io/packages/helm/apache-hadoop-helm/hadoop

helm repo add apache-hadoop-helm https://pfisterer.github.io/apache-hadoop-helm/
helm pull apache-hadoop-helm/hadoop --version 1.2.0
tar -xf hadoop-1.2.0.tgz

2）构建镜像 Dockerfile

FROM myharbor.com/bigdata/centos:7.9.2009
RUN rm -f /etc/localtime && ln -sv /usr/share/zoneinfo/Asia/Shanghai /etc/localtime && echo "Asia/Shanghai" > /etc/timezone
RUN export LANG=zh_CN.UTF-8
# 创建用户和用户组，跟yaml编排里的spec.template.spec.containers. securityContext.runAsUser: 9999
RUN groupadd --system --gid=9999 admin && useradd --system --home-dir /home/admin --uid=9999 --gid=admin admin
# 安装sudo
RUN yum -y install sudo ; chmod 640 /etc/sudoers
# 给admin添加sudo权限
RUN echo "admin ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers
RUN yum -y install install net-tools telnet wget
RUN mkdir /opt/apache/
ADD jdk-8u212-linux-x64.tar.gz /opt/apache/
ENV JAVA_HOME=/opt/apache/jdk1.8.0_212
ENV PATH=$JAVA_HOME/bin:$PATH
ENV HADOOP_VERSION 3.3.2
ENV HADOOP_HOME=/opt/apache/hadoop
ENV HADOOP_COMMON_HOME=${HADOOP_HOME} \
    HADOOP_HDFS_HOME=${HADOOP_HOME} \
    HADOOP_MAPRED_HOME=${HADOOP_HOME} \
    HADOOP_YARN_HOME=${HADOOP_HOME} \
    HADOOP_CONF_DIR=${HADOOP_HOME}/etc/hadoop \
    PATH=${PATH}:${HADOOP_HOME}/bin
#RUN curl --silent --output /tmp/hadoop.tgz https://ftp-stud.hs-esslingen.de/pub/Mirrors/ftp.apache.org/dist/hadoop/common/hadoop-${HADOOP_VERSION}/hadoop-${HADOOP_VERSION}.tar.gz && tar --directory /opt/apache -xzf /tmp/hadoop.tgz && rm /tmp/hadoop.tgz
ADD hadoop-${HADOOP_VERSION}.tar.gz /opt/apache
RUN ln -s /opt/apache/hadoop-${HADOOP_VERSION} ${HADOOP_HOME}
RUN chown -R admin:admin /opt/apache
WORKDIR $HADOOP_HOME
# Hdfs ports
EXPOSE 50010 50020 50070 50075 50090 8020 9000
# Mapred ports
EXPOSE 19888
#Yarn ports
EXPOSE 8030 8031 8032 8033 8040 8042 8088
#Other ports
EXPOSE 49707 2122

开始构建镜像

docker build -t myharbor.com/bigdata/hadoop:3.3.2 . --no-cache
### 参数解释
# -t：指定镜像名称
# . ：当前目录Dockerfile
# -f：指定Dockerfile路径
#  --no-cache：不缓存

推送到镜像仓库

docker push myharbor.com/bigdata/hadoop:3.3.2

调整目录结构

mkdir hadoop/templates/hdfs hadoop/templates/yarn
mv hadoop/templates/hdfs-* hadoop/templates/hdfs/
mv hadoop/templates/yarn-* hadoop/templates/yarn/

3）修改配置

hadoop/values.yaml

image:
  repository: myharbor.com/bigdata/hadoop
  tag: 3.3.2
  pullPolicy: IfNotPresent
...
persistence:
  nameNode:
    enabled: true
    storageClass: "hadoop-nn-local-storage"
    accessMode: ReadWriteOnce
    size: 10Gi
    local:
    - name: hadoop-nn-0
      host: "local-168-182-110"
      path: "/opt/bigdata/servers/hadoop/nn/data/data1"
  dataNode:
    enabled: true
    storageClass: "hadoop-dn-local-storage"
    accessMode: ReadWriteOnce
    size: 20Gi
    local:
    - name: hadoop-dn-0
      host: "local-168-182-110"
      path: "/opt/bigdata/servers/hadoop/dn/data/data1"
    - name: hadoop-dn-1
      host: "local-168-182-110"
      path: "/opt/bigdata/servers/hadoop/dn/data/data2"
    - name: hadoop-dn-2
      host: "local-168-182-110"
      path: "/opt/bigdata/servers/hadoop/dn/data/data3"
    - name: hadoop-dn-3
      host: "local-168-182-111"
      path: "/opt/bigdata/servers/hadoop/dn/data/data1"
    - name: hadoop-dn-4
      host: "local-168-182-111"
      path: "/opt/bigdata/servers/hadoop/dn/data/data2"
    - name: hadoop-dn-5
      host: "local-168-182-111"
      path: "/opt/bigdata/servers/hadoop/dn/data/data3"
    - name: hadoop-dn-6
      host: "local-168-182-112"
      path: "/opt/bigdata/servers/hadoop/dn/data/data1"
    - name: hadoop-dn-7
      host: "local-168-182-112"
      path: "/opt/bigdata/servers/hadoop/dn/data/data2"
   - name: hadoop-dn-8
      host: "local-168-182-112"
      path: "/opt/bigdata/servers/hadoop/dn/data/data3"
...
service:
  nameNode:
    type: NodePort
    ports:
      dfs: 9000
      webhdfs: 9870
    nodePorts:
      dfs: 30900
      webhdfs: 30870
  dataNode:
    type: NodePort
    ports:
      dfs: 9000
      webhdfs: 9864
    nodePorts:
      dfs: 30901
      webhdfs: 30864
  resourceManager:
    type: NodePort
    ports:
      web: 8088
    nodePorts:
      web: 30088
...
securityContext:
  runAsUser: 9999
  privileged: true

hadoop/templates/hdfs/hdfs-nn-pv.yaml

{{- range .Values.persistence.nameNode.local }}
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: {{ .name }}
  labels:
    name: {{ .name }}
spec:
  storageClassName: {{ $.Values.persistence.nameNode.storageClass }}
  capacity:
    storage: {{ $.Values.persistence.nameNode.size }}
  accessModes:
    - ReadWriteOnce
  local:
    path: {{ .path }}
  nodeAffinity:
    required:
      nodeSelectorTerms:
        - matchExpressions:
            - key: kubernetes.io/hostname
              operator: In
              values:
                - {{ .host }}
---
{{- end }}

hadoop/templates/hdfs/hdfs-dn-pv.yaml

{{- range .Values.persistence.dataNode.local }}
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: {{ .name }}
  labels:
    name: {{ .name }}
spec:
  storageClassName: {{ $.Values.persistence.dataNode.storageClass }}
  capacity:
    storage: {{ $.Values.persistence.dataNode.size }}
  accessModes:
    - ReadWriteOnce
  local:
    path: {{ .path }}
  nodeAffinity:
    required:
      nodeSelectorTerms:
        - matchExpressions:
            - key: kubernetes.io/hostname
              operator: In
              values:
                - {{ .host }}
---
{{- end }}

修改 hdfs service

mv hadoop/templates/hdfs/hdfs-nn-svc.yaml hadoop/templates/hdfs/hdfs-nn-svc-headless.yaml
mv hadoop/templates/hdfs/hdfs-dn-svc.yaml hadoop/templates/hdfs/hdfs-dn-svc-headless.yaml
# 注意修改名称，不要重复

hadoop/templates/hdfs/hdfs-nn-svc.yaml

# A headless service to create DNS records
apiVersion: v1
kind: Service
metadata:
  name: {{ include "hadoop.fullname" . }}-hdfs-nn
  labels:
    app.kubernetes.io/name: {{ include "hadoop.name" . }}
    helm.sh/chart: {{ include "hadoop.chart" . }}
    app.kubernetes.io/instance: {{ .Release.Name }}
    app.kubernetes.io/component: hdfs-nn
spec:
  ports:
  - name: dfs
    port: {{ .Values.service.nameNode.ports.dfs }}
    protocol: TCP
    nodePort: {{ .Values.service.nameNode.nodePorts.dfs }}
  - name: webhdfs
    port: {{ .Values.service.nameNode.ports.webhdfs }}
    nodePort: {{ .Values.service.nameNode.nodePorts.webhdfs }}
  type: {{ .Values.service.nameNode.type }}
  selector:
    app.kubernetes.io/name: {{ include "hadoop.name" . }}
    app.kubernetes.io/instance: {{ .Release.Name }}
    app.kubernetes.io/component: hdfs-nn

hadoop/templates/hdfs/hdfs-dn-svc.yaml

# A headless service to create DNS records
apiVersion: v1
kind: Service
metadata:
  name: {{ include "hadoop.fullname" . }}-hdfs-dn
  labels:
    app.kubernetes.io/name: {{ include "hadoop.name" . }}
    helm.sh/chart: {{ include "hadoop.chart" . }}
    app.kubernetes.io/instance: {{ .Release.Name }}
    app.kubernetes.io/component: hdfs-nn
spec:
  ports:
  - name: dfs
    port: {{ .Values.service.dataNode.ports.dfs }}
    protocol: TCP
    nodePort: {{ .Values.service.dataNode.nodePorts.dfs }}
  - name: webhdfs
    port: {{ .Values.service.dataNode.ports.webhdfs }}
    nodePort: {{ .Values.service.dataNode.nodePorts.webhdfs }}
  type: {{ .Values.service.dataNode.type }}
  selector:
    app.kubernetes.io/name: {{ include "hadoop.name" . }}
    app.kubernetes.io/instance: {{ .Release.Name }}
    app.kubernetes.io/component: hdfs-dn

修改 yarn service

mv hadoop/templates/yarn/yarn-nm-svc.yaml hadoop/templates/yarn/yarn-nm-svc-headless.yaml
mv hadoop/templates/yarn/yarn-rm-svc.yaml hadoop/templates/yarn/yarn-rm-svc-headless.yaml
mv hadoop/templates/yarn/yarn-ui-svc.yaml hadoop/templates/yarn/yarn-rm-svc.yaml
# 注意修改名称，不要重复

hadoop/templates/yarn/yarn-rm-svc.yaml

# Service to access the yarn web ui
apiVersion: v1
kind: Service
metadata:
  name: {{ include "hadoop.fullname" . }}-yarn-rm
  labels:
    app.kubernetes.io/name: {{ include "hadoop.name" . }}
    helm.sh/chart: {{ include "hadoop.chart" . }}
    app.kubernetes.io/instance: {{ .Release.Name }}
    app.kubernetes.io/component: yarn-rm
spec:
  ports:
  - port: {{ .Values.service.resourceManager.ports.web }}
    name: web
    nodePort: {{ .Values.service.resourceManager.nodePorts.web }}
  type: {{ .Values.service.resourceManager.type }}
  selector:
    app.kubernetes.io/name: {{ include "hadoop.name" . }}
    app.kubernetes.io/instance: {{ .Release.Name }}
    app.kubernetes.io/component: yarn-rm

修改控制器

在所有控制中新增如下内容：

containers:
...
  securityContext:
    runAsUser: {{ .Values.securityContext.runAsUser }}
    privileged: {{ .Values.securityContext.privileged }}

hadoop/templates/hadoop-configmap.yaml

### 1、将/root换成/opt/apache
### 2、TMP_URL="http://{{ include "hadoop.fullname" . }}-yarn-rm-headless:8088/ws/v1/cluster/info"

4）开始安装

# 创建存储目录
mkdir -p /opt/bigdata/servers/hadoop/{nn,dn}/data/data{1..3}
helm install hadoop ./hadoop -n hadoop --create-namespace

NOTES

NAME: hadoop
LAST DEPLOYED: Sat Sep 24 17:00:55 2022
NAMESPACE: hadoop
STATUS: deployed
REVISION: 1
TEST SUITE: None
NOTES:
1. You can check the status of HDFS by running this command:
   kubectl exec -n hadoop -it hadoop-hadoop-hdfs-nn-0 -- /opt/hadoop/bin/hdfs dfsadmin -report
2. You can list the yarn nodes by running this command:
   kubectl exec -n hadoop -it hadoop-hadoop-yarn-rm-0 -- /opt/hadoop/bin/yarn node -list
3. Create a port-forward to the yarn resource manager UI:
   kubectl port-forward -n hadoop hadoop-hadoop-yarn-rm-0 8088:8088
   Then open the ui in your browser:
   open http://localhost:8088
4. You can run included hadoop tests like this:
   kubectl exec -n hadoop -it hadoop-hadoop-yarn-nm-0 -- /opt/hadoop/bin/hadoop jar /opt/hadoop/share/hadoop/mapreduce/hadoop-mapreduce-client-jobclient-3.3.2-tests.jar TestDFSIO -write -nrFiles 5 -fileSize 128MB -resFile /tmp/TestDFSIOwrite.txt
5. You can list the mapreduce jobs like this:
   kubectl exec -n hadoop -it hadoop-hadoop-yarn-rm-0 -- /opt/hadoop/bin/mapred job -list
6. This chart can also be used with the zeppelin chart
    helm install --namespace hadoop --set hadoop.useConfigMap=true,hadoop.configMapName=hadoop-hadoop stable/zeppelin
7. You can scale the number of yarn nodes like this:
   helm upgrade hadoop --set yarn.nodeManager.replicas=4 stable/hadoop
   Make sure to update the values.yaml if you want to make this permanent.

查看

kubectl get pods,svc -n hadoop -owide

hdfs web：http://192.168.182.110:30870/

yarn web：http://192.168.182.110:30088/

5）测试验证

HDFS 测试验证

kubectl exec -it hadoop-hadoop-hdfs-nn-0 -n hadoop -- bash
[root@local-168-182-110 hadoop]# kubectl exec -it hadoop-hadoop-hdfs-nn-0 -n hadoop -- bash
bash-4.2$
bash-4.2$
bash-4.2$ hdfs dfs -mkdir /tmp
bash-4.2$ hdfs dfs -ls /
Found 1 items
drwxr-xr-x   - admin supergroup          0 2022-09-24 17:56 /tmp
bash-4.2$ echo "test hadoop" >test.txt
bash-4.2$ hdfs dfs -put test.txt /tmp/
bash-4.2$ hdfs dfs -ls /tmp/
Found 1 items
-rw-r--r--   3 admin supergroup         12 2022-09-24 17:57 /tmp/test.txt
bash-4.2$ hdfs dfs -cat /tmp/
cat: `/tmp': Is a directory
bash-4.2$ hdfs dfs -cat /tmp/test.txt
test hadoop
bash-4.2$

Yarn 的测试验证等后面讲到 hive on k8s 再来测试验证。

6）卸载

helm uninstall hadoop -n hadoop
kubectl delete pod -n hadoop `kubectl get pod -n hadoop|awk 'NR>1{print $1}'` --force
kubectl patch ns hadoop -p '{"metadata":{"finalizers":null}}'
kubectl delete ns hadoop --force

这里也提供 git 下载地址，有需要的小伙伴可以下载部署玩玩：https://gitee.com/hadoop-bigdata/hadoop-on-k8s

在 k8s 集群中 yarn 会慢慢被弱化，直接使用 k8s 资源调度，而不再使用 yarn 去调度资源了，这里只是部署了单点，仅限于测试环境使用，下一篇文章会讲 Hadoop 高可用 on k8s 实现，请小伙伴耐心等待。