2015-12-14注：加入新節點不更改運行節點參數需求已滿足，將在后續文章中陸續總結。
注：目前方案不滿足加入新節點（master節點或regionserver節點）而不更改已運行節點的參數的需求，具體討論見第六部分。
一、背景知識
先看下HBase的組成：
Master：Master主要負責管理RegionServer集群，如負載均衡及資源分配等，它本身也可以以集群方式運行，但同一時刻只有一個master處於激活狀態。當工作中的master宕掉后，zookeeper會切換到其它備選的master上。
RegionServer：負責具體數據塊的讀寫操作。
ZooKeeper：負責集群元數據的維護並監控集群的狀態以防止單點故障。部署HBase時可以使用自帶的ZooKeeper也可以使用獨立的集群，是HBase跑起來的先決條件。
HDFS：寫入HBase中的數據最終都持久化到了HDFS中，也是HBase運行的先決條件。
二、skyDNS部署
skyDNS並不是必需項，但設置了skyDNS后可以為k8s的service綁定域名，進行hbase的參數設置時可以以域名代替service的IP地址。k8s環境中的skyDNS由三部分組成： 存儲IP地址和域名映射關系的ETCD；進行域名解析的skyDNS；連接k8s和skyDNS的橋梁kube2sky。k8s的域名構成為 service_name.namespace.k8s_cluster_domain。k8s的文檔中有對部署skyDNS的簡略說明（戳這里），其中要用到Google鏡像倉庫中的image，國內訪問不到，可以使用DockerHub上的替換方案，如：
skyDNS: docker pull shenshouer/skydns:2015-09-22
kube2sky: docker pull shenshouer/kube2sky:1.11
ETCD: 只要是2.x版本的ETCD都可以，也可以和上面的保持一致使用 docker pull shenshouer/etcd:2.0.9
pull下來之后打上tag再push到私有倉庫中。
下面創建一個service和一個pod來部署skyDNS，設定 skyDNS service 的服務地址為 172.16.40.1 (53/UDP, 53/TCP)，注意該IP地址要在kube-apiserver啟動時設定的service的子網范圍內；k8s集群的域名后綴為 domeos.sohu，注意這個后綴的選擇最好包含兩部分，否則kube2sky可能會出問題（具體討論戳這里）。
首先創建skydns.yaml文件：
apiVersion: v1
kind: Service
metadata:
name: kube-dns labels: app: kube-dns version: v8 spec: selector: app: kube-dns version: v8 type: ClusterIP clusterIP: 172.16.40.1 ports: - name: dns port: 53 protocol: UDP - name: dns-tcp port: 53 protocol: TCP --- apiVersion: v1 kind: ReplicationController metadata: name: kube-dns-v8 labels: app: kube-dns version: v8 spec: replicas: 1 selector: app: kube-dns version: v8 template: metadata: labels: app: kube-dns version: v8 spec: containers: - name: etcd image: 10.11.150.76:5000/openxxs/etcd:2.0.3 command: - "etcd" args: - "--data-dir=/var/etcd/data" - "--listen-client-urls=http://127.0.0.1:2379,http://127.0.0.1:4001" - "--advertise-client-urls=http://127.0.0.1:2379,http://127.0.0.1:4001" - "--initial-cluster-token=skydns-etcd" volumeMounts: - name: etcd-storage mountPath: /var/etcd/data - name: kube2sky image: 10.11.150.76:5000/openxxs/kube2sky:k8s-dns args: - "--domain=domeos.sohu" - "--kube_master_url=http://10.16.42.200:8080" - name: skydns image: 10.11.150.76:5000/openxxs/skydns:2015-09-22 args: - "--machines=http://localhost:4001" - "--addr=0.0.0.0:53" - "--domain=domeos.sohu" ports: - containerPort: 53 name: dns protocol: UDP - containerPort: 53 name: dns-tcp protocol: TCP volumes: - name: etcd-storage emptyDir: {} dnsPolicy: Default
kube2sky中的 --kube_master_url 參數用於指定 kube-apiserver 的地址；kube2sky中的 --domain 和 skydns中的 --domain 要保持一致。
然后 kubectl create -f skydns.yaml 創建服務和pod：
$kubectl create -f skydns.yaml
service "kube-dns" created replicationcontroller "kube-dns-v8" created $kubectl get pods NAME READY STATUS RESTARTS AGE kube-dns-v8-61aie 3/3 Running 0 9s $kubectl get service NAME CLUSTER_IP EXTERNAL_IP PORT(S) SELECTOR AGE kube-dns 172.16.40.1 <none> 53/UDP,53/TCP app=kube-dns,version=v8 6m
最后，重啟 kubelet 加上dns相關的設置參數 --cluster_dns 和 --cluster_domain，參數值要與前面yaml文件中寫的一致，如：
./kubelet --logtostderr=true --v=0 --api_servers=http://bx-42-200:8080 --address=0.0.0.0 --hostname_override=bx-42-198 --allow_privileged=false --pod-infra-container-image=10.11.150.76:5000/kubernetes/pause:latest --cluster_dns=172.16.40.1 --cluster_domain=domeos.sohu &
注意：只有在kubelet加了dns設置參數重啟之后創建的pods才會使用skyDNS。
此時進入到etcd的container中就可以發現k8s的service域名信息已被寫入etcd當中了：
$ docker exec -it 13e243510e3e sh / # etcdctl ls --recursive / /skydns /skydns/sohu /skydns/sohu/domeos /skydns/sohu/domeos/default /skydns/sohu/domeos/default/kube-dns /skydns/sohu/domeos/default/kubernetes /skydns/sohu/domeos/default/zookeeper-1 /skydns/sohu/domeos/default/zookeeper-2 /skydns/sohu/domeos/default/zookeeper-3 /skydns/sohu/domeos/svc /skydns/sohu/domeos/svc/default /skydns/sohu/domeos/svc/default/zookeeper-2 /skydns/sohu/domeos/svc/default/zookeeper-2/b8757496 /skydns/sohu/domeos/svc/default/zookeeper-3 /skydns/sohu/domeos/svc/default/zookeeper-3/8687b21f /skydns/sohu/domeos/svc/default/kube-dns /skydns/sohu/domeos/svc/default/kube-dns/a9f11e6f /skydns/sohu/domeos/svc/default/kubernetes /skydns/sohu/domeos/svc/default/kubernetes/cf07aead /skydns/sohu/domeos/svc/default/zookeeper-1 /skydns/sohu/domeos/svc/default/zookeeper-1/75512011 / # etcdctl get /skydns/sohu/domeos/default/zookeeper-1 {"host":"172.16.11.1","priority":10,"weight":10,"ttl":30,"targetstrip":0}
以 /skydns/sohu/domeos/default/zookeeper-1 這條記錄為例，其對應的域名即為 zookeeper-1.default.domeos.sohu ，IP 為 172.16.11.1，服務名稱為zookeeper-1，k8s的namespace為default，k8s設定的域為 domeos.sohu。在任一重啟kubelet之后創建的pod中都可以以 zookeeper-1.default.domeos.sohu 的方式訪問zookeeper-1服務，如：
[@bx_42_199 ~]# docker exec -it 0662660e8708 /bin/bash [root@test-3-2h0fx /]# curl zookeeper-1.default.domeos.sohu:2181 curl: (52) Empty reply from server
三、HDFS集群部署
HDFS由namenode和datanode組成，首先從DockerHub上pull合適的鏡像再push到自己的私有倉庫中：
# pull 遠程images docker pull bioshrek/hadoop-hdfs-datanode:cdh5 docker pull bioshrek/hadoop-hdfs-namenode:cdh5 # 打上tag # docker tag <image的ID> <自己的私有倉庫IP:PORT/名稱:TAG> docker tag c89c3ebcccae 10.11.150.76:5000/hdfs-datanode:latest docker tag ca19d4c7e359 10.11.150.76:5000/hdfs-namenode:latest # push到倉庫中 docker push 10.11.150.76:5000/hdfs-datanode:latest docker push 10.11.150.76:5000/hdfs-namenode:latest
然后創建如下hdfs.yaml文件：
1 apiVersion: v1 2 kind: Service 3 metadata: 4 name: hdfs-namenode-service 5 spec: 6 selector: 7 app: hdfs-namenode 8 type: ClusterIP 9 clusterIP: "172.16.20.1" 10 ports: 11 - name: rpc 12 port: 4231 13 targetPort: 8020 14 - name: p1 15 port: 50020 16 - name: p2 17 port: 50090 18 - name: p3 19 port: 50070 20 - name: p4 21 port: 50010 22 - name: p5 23 port: 50075 24 - name: p6 25 port: 8031 26 - name: p7 27 port: 8032 28 - name: p8 29 port: 8033 30 - name: p9 31 port: 8040 32 - name: p10 33 port: 8042 34 - name: p11 35 port: 49707 36 - name: p12 37 port: 22 38 - name: p13 39 port: 8088 40 - name: p14 41 port: 8030 42 --- 43 apiVersion: v1 44 kind: ReplicationController 45 metadata: 46 name: hdfs-namenode-1 47 spec: 48 replicas: 1 49 template: 50 metadata: 51 labels: 52 app: hdfs-namenode 53 spec: 54 containers: 55 - name: hdfs-namenode 56 image: 10.11.150.76:5000/hdfs-namenode:latest 57 volumeMounts: 58 - name: data1 59 mountPath: /var/lib/hadoop-hdfs/cache/hdfs/dfs/name 60 - name: data2 61 mountPath: /home/chianyu/shared_with_docker_container/cdh5/nn 62 ports: 63 - containerPort: 50020 64 - containerPort: 50090 65 - containerPort: 50070 66 - containerPort: 50010 67 - containerPort: 50075 68 - containerPort: 8031 69 - containerPort: 8032 70 - containerPort: 8033 71 - containerPort: 8040 72 - containerPort: 8042 73 - containerPort: 49707 74 - containerPort: 22 75 - containerPort: 8088 76 - containerPort: 8030 77 - containerPort: 8020 78 nodeSelector: 79 kubernetes.io/hostname: bx-42-199 80 volumes: 81 - hostPath: 82 path: /data1/kubernetes/hdfs-namenode/data1 83 name: data1 84 - hostPath: 85 path: /data1/kubernetes/hdfs-namenode/data2 86 name: data2 87 --- 88 apiVersion: v1 89 kind: ReplicationController 90 metadata: 91 name: hdfs-datanode-1 92 spec: 93 replicas: 1 94 template: 95 metadata: 96 labels: 97 app: hdfs-datanode 98 server-id: "1" 99 spec: 100 containers: 101 - name: hdfs-datanode-1 102 image: 10.11.150.76:5000/hdfs-datanode:latest 103 volumeMounts: 104 - name: data1 105 mountPath: /var/lib/hadoop-hdfs/cache/hdfs/dfs/name 106 - name: data2 107 mountPath: /home/chianyu/shared_with_docker_container/cdh5/dn 108 env: 109 - name: HDFSNAMENODERPC_SERVICE_HOST 110 value: "172.16.20.1" 111 - name: HDFSNAMENODERPC_SERVICE_PORT 112 value: "4231" 113 ports: 114 - containerPort: 50020 115 - containerPort: 50090 116 - containerPort: 50070 117 - containerPort: 50010 118 - containerPort: 50075 119 - containerPort: 8031 120 - containerPort: 8032 121 - containerPort: 8033 122 - containerPort: 8040 123 - containerPort: 8042 124 - containerPort: 49707 125 - containerPort: 22 126 - containerPort: 8088 127 - containerPort: 8030 128 - containerPort: 8020 129 nodeSelector: 130 kubernetes.io/hostname: bx-42-199 131 volumes: 132 - hostPath: 133 path: /data1/kubernetes/hdfs-datanode1/data1 134 name: data1 135 - hostPath: 136 path: /data1/kubernetes/hdfs-datanode1/data2 137 name: data2 138 --- 139 apiVersion: v1 140 kind: ReplicationController 141 metadata: 142 name: hdfs-datanode-2 143 spec: 144 replicas: 1 145 template: 146 metadata: 147 labels: 148 app: hdfs-datanode 149 server-id: "2" 150 spec: 151 containers: 152 - name: hdfs-datanode-2 153 image: 10.11.150.76:5000/hdfs-datanode:latest 154 volumeMounts: 155 - name: data1 156 mountPath: /var/lib/hadoop-hdfs/cache/hdfs/dfs/name 157 - name: data2 158 mountPath: /home/chianyu/shared_with_docker_container/cdh5/dn 159 env: 160 - name: HDFSNAMENODERPC_SERVICE_HOST 161 value: "172.16.20.1" 162 - name: HDFSNAMENODERPC_SERVICE_PORT 163 value: "4231" 164 ports: 165 - containerPort: 50020 166 - containerPort: 50090 167 - containerPort: 50070 168 - containerPort: 50010 169 - containerPort: 50075 170 - containerPort: 8031 171 - containerPort: 8032 172 - containerPort: 8033 173 - containerPort: 8040 174 - containerPort: 8042 175 - containerPort: 49707 176 - containerPort: 22 177 - containerPort: 8088 178 - containerPort: 8030 179 nodeSelector: 180 kubernetes.io/hostname: bx-42-199 181 volumes: 182 - name: data1 183 hostPath: 184 path: /data2/kubernetes/hdfs-datanode2/data1 185 - name: data2 186 hostPath: 187 path: /data2/kubernetes/hdfs-datanode2/data2 188 --- 189 apiVersion: v1 190 kind: ReplicationController 191 metadata: 192 name: hdfs-datanode-3 193 spec: 194 replicas: 1 195 template: 196 metadata: 197 labels: 198 app: hdfs-datanode 199 server-id: "3" 200 spec: 201 containers: 202 - name: hdfs-datanode-3 203 image: 10.11.150.76:5000/hdfs-datanode:latest 204 volumeMounts: 205 - name: data1 206 mountPath: /var/lib/hadoop-hdfs/cache/hdfs/dfs/name 207 - name: data2 208 mountPath: /home/chianyu/shared_with_docker_container/cdh5/dn 209 env: 210 - name: HDFSNAMENODERPC_SERVICE_HOST 211 value: "172.16.20.1" 212 - name: HDFSNAMENODERPC_SERVICE_PORT 213 value: "4231" 214 ports: 215 - containerPort: 50020 216 - containerPort: 50090 217 - containerPort: 50070 218 - containerPort: 50010 219 - containerPort: 50075 220 - containerPort: 8031 221 - containerPort: 8032 222 - containerPort: 8033 223 - containerPort: 8040 224 - containerPort: 8042 225 - containerPort: 49707 226 - containerPort: 22 227 - containerPort: 8088 228 - containerPort: 8030 229 nodeSelector: 230 kubernetes.io/hostname: bx-42-199 231 volumes: 232 - name: data1 233 hostPath: 234 path: /data3/kubernetes/hdfs-datanode3/data1 235 - name: data2 236 hostPath: 237 path: /data3/kubernetes/hdfs-datanode3/data2
通過 kubectl create -f hdfs.yaml 即創建一個名為hdfs-namenode-service的service，四個分別名為hdfs-namenode-1、hdfs-datanode-1、hdfs-datanode-2、hdfs-datanode-3的RC。通過 kubectl get services/rc/pods 可以看到對應的service和pod都已經正常啟動了。
下面對HDFS進行測試是否可以正常使用：
# 查看HDFS pods kubectl get pods # 通過describe查看pods跑在哪個k8s node上 kubectl describe pod hdfs-datanode-3-h4jvt # 進入容器內部 docker ps | grep hdfs-datanode-3 docker exec -it 2e2c4df0c0a9 /bin/bash # 切換至 hdfs 用戶 su hdfs # 創建目錄 hadoop fs -mkdir /test # 創建本地文件 echo "Hello" > hello # 將本地文件復制到HDFS文件系統中 hadoop fs -put hello /test # 查看HDFS中的文件信息 hadoop fs -ls /test # 類似的，可以 docker exec 到其它datanode中查看文件信息，如： root@hdfs-datanode-1-nek2l:/# hadoop fs -ls /test Found 1 items -rw-r--r-- 2 hdfs hadoop 6 2015-11-27 08:36 /test/hello
四、ZooKeeper集群部署
在 fabric8/zookeeper 的image基礎上進行修改，修改后Dockerfile文件內容如下：
1 FROM jboss/base-jdk:7 2 3 MAINTAINER iocanel@gmail.com 4 5 USER root 6 7 ENV ZOOKEEPER_VERSION 3.4.6 8 EXPOSE 2181 2888 3888 9 10 RUN yum -y install wget bind-utils && yum clean all \ 11 && wget -q -O - http://apache.mirrors.pair.com/zookeeper/zookeeper-${ZOOKEEPER_VERSION}/zookeeper-${ZOOKEEPER_VERSION}.tar.gz | tar -xzf - -C /opt \ 12 && mv /opt/zookeeper-${ZOOKEEPER_VERSION} /opt/zookeeper \ 13 && cp /opt/zookeeper/conf/zoo_sample.cfg /opt/zookeeper/conf/zoo.cfg \ 14 && mkdir -p /opt/zookeeper/{data,log} 15 16 WORKDIR /opt/zookeeper 17 VOLUME ["/opt/zookeeper/conf", "/opt/zookeeper/data", "/opt/zookeeper/log"] 18 19 COPY config-and-run.sh ./bin/ 20 COPY zoo.cfg ./conf/ 21 22 CMD ["/opt/zookeeper/bin/config-and-run.sh"]
zoo.cfg 文件內容如下：
1 # The number of milliseconds of each tick 2 tickTime=2000 3 # The number of ticks that the initial 4 # synchronization phase can take 5 initLimit=10 6 # The number of ticks that can pass between 7 # sending a request and getting an acknowledgement 8 syncLimit=5 9 # the directory where the snapshot is stored. 10 dataDir=/opt/zookeeper/data 11 #This option will direct the machine to write the transaction log to the dataLogDir rather than the dataDir. This allows a dedicated log device to be used, and helps avoid competition between logging and snaphots. 12 dataLogDir=/opt/zookeeper/log 13 14 # the port at which the clients will connect 15 clientPort=2181 16 # 17 # Be sure to read the maintenance section of the 18 # administrator guide before turning on autopurge. 19 # 20 # http://zookeeper.apache.org/doc/current/zookeeperAdmin.html#sc_maintenance 21 # 22 # The number of snapshots to retain in dataDir 23 #autopurge.snapRetainCount=3 24 # Purge task interval in hours 25 # Set to "0" to disable auto purge feature 26 #autopurge.purgeInterval=1
config-and-run.sh 文件內容如下：
#!/bin/bash echo "$SERVER_ID / $MAX_SERVERS" if [ ! -z "$SERVER_ID" ] && [ ! -z "$MAX_SERVERS" ]; then echo "Starting up in clustered mode" echo "" >> /opt/zookeeper/conf/zoo.cfg echo "#Server List" >> /opt/zookeeper/conf/zoo.cfg for i in $( eval echo {1..$MAX_SERVERS});do HostEnv="ZOOKEEPER_${i}_SERVICE_HOST" HOST=${!HostEnv} FollowerPortEnv="ZOOKEEPER_${i}_SERVICE_PORT_FOLLOWERS" FOLLOWERPORT=${!FollowerPortEnv} ElectionPortEnv="ZOOKEEPER_${i}_SERVICE_PORT_ELECTION" ELECTIONPORT=${!ElectionPortEnv} if [ "$SERVER_ID" = "$i" ];then echo "server.$i=0.0.0.0:$FOLLOWERPORT:$ELECTIONPORT" >> /opt/zookeeper/conf/zoo.cfg else echo "server.$i=$HOST:$FOLLOWERPORT:$ELECTIONPORT" >> /opt/zookeeper/conf/zoo.cfg fi done cat /opt/zookeeper/conf/zoo.cfg # Persists the ID of the current instance of Zookeeper echo ${SERVER_ID} > /opt/zookeeper/data/myid else echo "Starting up in standalone mode" fi exec /opt/zookeeper/bin/zkServer.sh start-foreground
修改完后創建鏡像並push到私有倉庫中(鏡像名為10.11.150.76:5000/zookeeper-kb:3.4.6-1)。
創建zookeeper.yaml文件：
1 apiVersion: v1 2 kind: Service 3 metadata: 4 name: zookeeper-1 5 labels: 6 name: zookeeper-1 7 spec: 8 ports: 9 - name: client 10 port: 2181 11 targetPort: 2181 12 - name: followers 13 port: 2888 14 targetPort: 2888 15 - name: election 16 port: 3888 17 targetPort: 3888 18 selector: 19 name: zookeeper 20 server-id: "1" 21 type: ClusterIP 22 clusterIP: 172.16.11.1 23 --- 24 apiVersion: v1 25 kind: Service 26 metadata: 27 name: zookeeper-2 28 labels: 29 name: zookeeper-2 30 spec: 31 ports: 32 - name: client 33 port: 2181 34 targetPort: 2181 35 - name: followers 36 port: 2888 37 targetPort: 2888 38 - name: election 39 port: 3888 40 targetPort: 3888 41 selector: 42 name: zookeeper 43 server-id: "2" 44 type: ClusterIP 45 clusterIP: 172.16.11.2 46 --- 47 apiVersion: v1 48 kind: Service 49 metadata: 50 name: zookeeper-3 51 labels: 52 name: zookeeper-3 53 spec: 54 ports: 55 - name: client 56 port: 2181 57 targetPort: 2181 58 - name: followers 59 port: 2888 60 targetPort: 2888 61 - name: election 62 port: 3888 63 targetPort: 3888 64 selector: 65 name: zookeeper 66 server-id: "3" 67 type: ClusterIP 68 clusterIP: 172.16.11.3 69 --- 70 apiVersion: v1 71 kind: ReplicationController 72 metadata: 73 name: zookeeper-1 74 spec: 75 replicas: 1 76 template: 77 metadata: 78 labels: 79 name: zookeeper 80 server-id: "1" 81 spec: 82 volumes: 83 - hostPath: 84 path: /data1/kubernetes/zookeeper/data1 85 name: data 86 - hostPath: 87 path: /data1/kubernetes/zookeeper/log1 88 name: log 89 containers: 90 - name: server 91 image: 10.11.150.76:5000/zookeeper-kb:3.4.6-1 92 env: 93 - name: SERVER_ID 94 value: "1" 95 - name: MAX_SERVERS 96 value: "3" 97 ports: 98 - containerPort: 2181 99 - containerPort: 2888 100 - containerPort: 3888 101 volumeMounts: 102 - mountPath: /opt/zookeeper/data 103 name: data 104 - mountPath: /opt/zookeeper/log 105 name: log 106 nodeSelector: 107 kubernetes.io/hostname: bx-42-199 108 --- 109 apiVersion: v1 110 kind: ReplicationController 111 metadata: 112 name: zookeeper-2 113 spec: 114 replicas: 1 115 template: 116 metadata: 117 labels: 118 name: zookeeper 119 server-id: "2" 120 spec: 121 volumes: 122 - hostPath: 123 path: /data1/kubernetes/zookeeper/data2 124 name: data 125 - hostPath: 126 path: /data1/kubernetes/zookeeper/log2 127 name: log 128 containers: 129 - name: server 130 image: 10.11.150.76:5000/zookeeper-kb:3.4.6-1 131 env: 132 - name: SERVER_ID 133 value: "2" 134 - name: MAX_SERVERS 135 value: "3" 136 ports: 137 - containerPort: 2181 138 - containerPort: 2888 139 - containerPort: 3888 140 volumeMounts: 141 - mountPath: /opt/zookeeper/data 142 name: data 143 - mountPath: /opt/zookeeper/log 144 name: log 145 nodeSelector: 146 kubernetes.io/hostname: bx-42-199 147 --- 148 apiVersion: v1 149 kind: ReplicationController 150 metadata: 151 name: zookeeper-3 152 spec: 153 replicas: 1 154 template: 155 metadata: 156 labels: 157 name: zookeeper 158 server-id: "3" 159 spec: 160 volumes: 161 - hostPath: 162 path: /data1/kubernetes/zookeeper/data3 163 name: data 164 - hostPath: 165 path: /data1/kubernetes/zookeeper/log3 166 name: log 167 containers: 168 - name: server 169 image: 10.11.150.76:5000/zookeeper-kb:3.4.6-1 170 env: 171 - name: SERVER_ID 172 value: "3" 173 - name: MAX_SERVERS 174 value: "3" 175 ports: 176 - containerPort: 2181 177 - containerPort: 2888 178 - containerPort: 3888 179 volumeMounts: 180 - mountPath: /opt/zookeeper/data 181 name: data 182 - mountPath: /opt/zookeeper/log 183 name: log 184 nodeSelector: 185 kubernetes.io/hostname: bx-42-199
通過 kubectl create -f zookeeper.yaml 創建三個service和對應的RC。注意container中已經把ZooKeeper的data和log目錄映射到了主機的對應目錄上用於持久化存儲。
創建完之后即可進行測試：
# 進入zookeeper對應的容器后找到zkCli.sh，用該客戶端進行測試 /opt/zookeeper/bin/zkCli.sh [zk: localhost:2181(CONNECTED) 0] # 連接到k8s創建的zookeeper service (三個service任意一個都行) [zk: localhost:2181(CONNECTED) 0] connect 172.16.11.2:2181 [zk: 172.16.11.2:2181(CONNECTED) 1] # 查看目錄信息 [zk: 172.16.11.2:2181(CONNECTED) 1] ls / [zookeeper] [zk: 172.16.11.2:2181(CONNECTED) 2] get /zookeeper cZxid = 0x0 ctime = Thu Jan 01 00:00:00 UTC 1970 mZxid = 0x0 mtime = Thu Jan 01 00:00:00 UTC 1970 pZxid = 0x0 cversion = -1 dataVersion = 0 aclVersion = 0 ephemeralOwner = 0x0 dataLength = 0 numChildren = 1 [zk: 172.16.11.2:2181(CONNECTED) 3]
五、HBase部署
以上准備工作做好后，下面部署具有兩個master和兩個regionserver的HBase集群，其中兩個master分別位於兩個節點上，兩個regionserver也分別位於兩個節點上；使用獨立的HDFS和ZooKeeper服務。
首先需要創建HBase的鏡像，選擇的HBase版本為hbase-0.98.10.1-hadoop2。Dockerfile內容如下：
1 FROM centos:6.6 2 MAINTAINER openxxs <xiaoshengxu@sohu-inc.com> 3 4 RUN yum install -y java-1.7.0-openjdk-devel.x86_64 5 ENV JAVA_HOME=/usr/lib/jvm/jre 6 7 RUN yum install -y nc \ 8 && yum install -y tar \ 9 && mkdir /hbase-setup 10 11 WORKDIR /hbase-setup 12 13 COPY hbase-0.98.10.1-hadoop2-bin.tar.gz /hbase-setup/hbase-0.98.10.1-hadoop2-bin.tar.gz 14 RUN tar zxf hbase-0.98.10.1-hadoop2-bin.tar.gz -C /opt/ \ 15 && ln -s /opt/hbase-0.98.10.1-hadoop2 /opt/hbase 16 17 ADD hbase-site.xml /opt/hbase/conf/hbase-site.xml 18 ADD start-k8s-hbase.sh /opt/hbase/bin/start-k8s-hbase.sh 19 RUN chmod +x /opt/hbase/bin/start-k8s-hbase.sh 20 21 WORKDIR /opt/hbase/bin 22 23 ENV PATH=$PATH:/opt/hbase/bin 24 25 CMD /opt/hbase/bin/start-k8s-hbase.sh
配置文件hbase-site.xml內容如下：
<?xml version="1.0"?> <?xml-stylesheet type="text/xsl" href="configuration.xsl"?> <configuration> <property> <name>hbase.cluster.distributed</name> <value>true</value> </property> <property> <name>hbase.master.port</name> <value>@HBASE_MASTER_PORT@</value> </property> <property> <name>hbase.master.info.port</name> <value>@HBASE_MASTER_INFO_PORT@</value> </property> <property> <name>hbase.regionserver.port</name> <value>@HBASE_REGION_PORT@</value> </property> <property> <name>hbase.regionserver.info.port</name> <value>@HBASE_REGION_INFO_PORT@</value> </property> <property> <name>hbase.rootdir</name> <value>hdfs://@HDFS_PATH@/@ZNODE_PARENT@</value> </property> <property> <name>hbase.zookeeper.quorum</name> <value>@ZOOKEEPER_IP_LIST@</value> </property> <property> <name>hbase.zookeeper.property.clientPort</name> <value>@ZOOKEEPER_PORT@</value> </property> <property> <name>zookeeper.znode.parent</name> <value>/@ZNODE_PARENT@</value> </property> </configuration>
啟動腳本 start-k8s-hbase.sh 主要完成參數替換、寫入/etc/hosts、啟動 hbase 的功能，內容如下：
1 #!/bin/bash 2 3 export HBASE_CONF_FILE=/opt/hbase/conf/hbase-site.xml 4 export HADOOP_USER_NAME=hdfs 5 export HBASE_MANAGES_ZK=false 6 7 sed -i "s/@HBASE_MASTER_PORT@/$HBASE_MASTER_PORT/g" $HBASE_CONF_FILE 8 sed -i "s/@HBASE_MASTER_INFO_PORT@/$HBASE_MASTER_INFO_PORT/g" $HBASE_CONF_FILE 9 sed -i "s/@HBASE_REGION_PORT@/$HBASE_REGION_PORT/g" $HBASE_CONF_FILE 10 sed -i "s/@HBASE_REGION_INFO_PORT@/$HBASE_REGION_INFO_PORT/g" $HBASE_CONF_FILE 11 sed -i "s/@HDFS_PATH@/$HDFS_SERVICE:$HDFS_PORT\/$ZNODE_PARENT/g" $HBASE_CONF_FILE 12 sed -i "s/@ZOOKEEPER_IP_LIST@/$ZOOKEEPER_SERVICE_LIST/g" $HBASE_CONF_FILE 13 sed -i "s/@ZOOKEEPER_PORT@/$ZOOKEEPER_PORT/g" $HBASE_CONF_FILE 14 sed -i "s/@ZNODE_PARENT@/$ZNODE_PARENT/g" $HBASE_CONF_FILE 15 16 for i in ${HBASE_MASTER_LIST[@]} 17 do 18 arr=(${i//:/ }) 19 echo "${arr[0]} ${arr[1]}" >> /etc/hosts 20 done 21 22 for i in ${HBASE_REGION_LIST[@]} 23 do 24 arr=(${i//:/ }) 25 echo "${arr[0]} ${arr[1]}" >> /etc/hosts 26 done 27 28 if [ "$HBASE_SERVER_TYPE" = "master" ]; then 29 /opt/hbase/bin/hbase master start > logmaster.log 2>&1 30 elif [ "$HBASE_SERVER_TYPE" = "regionserver" ]; then 31 /opt/hbase/bin/hbase regionserver start > logregion.log 2>&1 32 fi
其中導出HADOOP_USER_NAME為hdfs用戶，否則會報Permission Denied的錯誤；HBASE_MANAGES_ZK=false表示不使用HBase自帶的ZooKeeper；HBASE_MASTER_LIST為HBase集群中除當前master外的其余master的服務地址和pod名的對應關系；HBASE_REGION_LIST為HBase集群中除當前regionserver外的其余regionserver的服務地址和pod名的對應關系；最后根據 HBASE_SERVER_TYPE 的取值來確定是啟master還是regionserver。
准備好這些文件后即可創建HBase的image：
docker build -t 10.11.150.76:5000/openxxs/hbase:1.0 . docker push 10.11.150.76:5000/openxxs/hbase:1.0
隨后創建hbase.yaml文件，內容如下：
1 apiVersion: v1 2 kind: Service 3 metadata: 4 name: hbase-master-1 5 spec: 6 selector: 7 app: hbase-master 8 server-id: "1" 9 type: ClusterIP 10 clusterIP: "172.16.30.1" 11 ports: 12 - name: rpc 13 port: 60000 14 targetPort: 60000 15 - name: info 16 port: 60001 17 targetPort: 60001 18 --- 19 apiVersion: v1 20 kind: Service 21 metadata: 22 name: hbase-master-2 23 spec: 24 selector: 25 app: hbase-master 26 server-id: "2" 27 type: ClusterIP 28 clusterIP: "172.16.30.2" 29 ports: 30 - name: rpc 31 port: 60000 32 targetPort: 60000 33 - name: info 34 port: 60001 35 targetPort: 60001 36 --- 37 apiVersion: v1 38 kind: Service 39 metadata: 40 name: hbase-region-1 41 spec: 42 selector: 43 app: hbase-region 44 server-id: "1" 45 type: ClusterIP 46 clusterIP: "172.16.30.3" 47 ports: 48 - name: rpc 49 port: 60010 50 targetPort: 60010 51 - name: info 52 port: 60011 53 targetPort: 60011 54 --- 55 apiVersion: v1 56 kind: Service 57 metadata: 58 name: hbase-region-2 59 spec: 60 selector: 61 app: hbase-region 62 server-id: "2" 63 type: ClusterIP 64 clusterIP: "172.16.30.4" 65 ports: 66 - name: rpc 67 port: 60010 68 targetPort: 60010 69 - name: info 70 port: 60011 71 targetPort: 60011 72 --- 73 apiVersion: v1 74 kind: Pod 75 metadata: 76 name: hbase-master-1 77 labels: 78 app: hbase-master 79 server-id: "1" 80 spec: 81 containers: 82 - name: hbase-master-1 83 image: 10.11.150.76:5000/openxxs/hbase:1.0 84 ports: 85 - containerPort: 60000 86 - containerPort: 60001 87 env: 88 - name: HBASE_SERVER_TYPE 89 value: master 90 - name: HBASE_MASTER_PORT 91 value: "60000" 92 - name: HBASE_MASTER_INFO_PORT 93 value: "60001" 94 - name: HBASE_REGION_PORT 95 value: "60010" 96 - name: HBASE_REGION_INFO_PORT 97 value: "60011" 98 - name: HDFS_SERVICE 99 value: "hdfs-namenode-service.default.domeos.sohu" 100 - name: HDFS_PORT 101 value: "4231" 102 - name: ZOOKEEPER_SERVICE_LIST 103 value: "zookeeper-1.default.domeos.sohu,zookeeper-2.default.domeos.sohu,zookeeper-3.default.domeos.sohu" 104 - name: ZOOKEEPER_PORT 105 value: "2181" 106 - name: ZNODE_PARENT 107 value: hbase 108 - name: HBASE_MASTER_LIST 109 value: "172.16.30.2:hbase-master-2" 110 - name: HBASE_REGION_LIST 111 value: "172.16.30.3:hbase-region-1 172.16.30.4:hbase-region-2" 112 restartPolicy: Always 113 nodeSelector: 114 kubernetes.io/hostname: bx-42-199 115 --- 116 apiVersion: v1 117 kind: Pod 118 metadata: 119 name: hbase-master-2 120 labels: 121 app: hbase-master 122 server-id: "2" 123 spec: 124 containers: 125 - name: hbase-master-1 126 image: 10.11.150.76:5000/openxxs/hbase:1.0 127 ports: 128 - containerPort: 60000 129 - containerPort: 60001 130 env: 131 - name: HBASE_SERVER_TYPE 132 value: master 133 - name: HBASE_MASTER_PORT 134 value: "60000" 135 - name: HBASE_MASTER_INFO_PORT 136 value: "60001" 137 - name: HBASE_REGION_PORT 138 value: "60010" 139 - name: HBASE_REGION_INFO_PORT 140 value: "60011" 141 - name: HDFS_SERVICE 142 value: "hdfs-namenode-service.default.domeos.sohu" 143 - name: HDFS_PORT 144 value: "4231" 145 - name: ZOOKEEPER_SERVICE_LIST 146 value: "zookeeper-1.default.domeos.sohu,zookeeper-2.default.domeos.sohu,zookeeper-3.default.domeos.sohu" 147 - name: ZOOKEEPER_PORT 148 value: "2181" 149 - name: ZNODE_PARENT 150 value: hbase 151 - name: HBASE_MASTER_LIST 152 value: "172.16.30.1:hbase-master-1" 153 - name: HBASE_REGION_LIST 154 value: "172.16.30.3:hbase-region-1 172.16.30.4:hbase-region-2" 155 restartPolicy: Always 156 nodeSelector: 157 kubernetes.io/hostname: bx-42-198 158 --- 159 apiVersion: v1 160 kind: Pod 161 metadata: 162 name: hbase-region-1 163 labels: 164 app: hbase-region-1 165 server-id: "1" 166 spec: 167 containers: 168 - name: hbase-region-1 169 image: 10.11.150.76:5000/openxxs/hbase:1.0 170 ports: 171 - containerPort: 60010 172 - containerPort: 60011 173 env: 174 - name: HBASE_SERVER_TYPE 175 value: regionserver 176 - name: HBASE_MASTER_PORT 177 value: "60000" 178 - name: HBASE_MASTER_INFO_PORT 179 value: "60001" 180 - name: HBASE_REGION_PORT 181 value: "60010" 182 - name: HBASE_REGION_INFO_PORT 183 value: "60011" 184 - name: HDFS_SERVICE 185 value: "hdfs-namenode-service.default.domeos.sohu" 186 - name: HDFS_PORT 187 value: "4231" 188 - name: ZOOKEEPER_SERVICE_LIST 189 value: "zookeeper-1.default.domeos.sohu,zookeeper-2.default.domeos.sohu,zookeeper-3.default.domeos.sohu" 190 - name: ZOOKEEPER_PORT 191 value: "2181" 192 - name: ZNODE_PARENT 193 value: hbase 194 - name: HBASE_MASTER_LIST 195 value: "172.16.30.1:hbase-master-1 172.16.30.2:hbase-master-2" 196 - name: HBASE_REGION_LIST 197 value: "172.16.30.4:hbase-region-2" 198 restartPolicy: Always 199 nodeSelector: 200 kubernetes.io/hostname: bx-42-199 201 --- 202 apiVersion: v1 203 kind: Pod 204 metadata: 205 name: hbase-region-2 206 labels: 207 app: hbase-region-2 208 server-id: "2" 209 spec: 210 containers: 211 - name: hbase-region-2 212 image: 10.11.150.76:5000/openxxs/hbase:1.0 213 ports: 214 - containerPort: 60010 215 - containerPort: 60011 216 env: 217 - name: HBASE_SERVER_TYPE 218 value: regionserver 219 - name: HBASE_MASTER_PORT 220 value: "60000" 221 - name: HBASE_MASTER_INFO_PORT 222 value: "60001" 223 - name: HBASE_REGION_PORT 224 value: "60010" 225 - name: HBASE_REGION_INFO_PORT 226 value: "60011" 227 - name: HDFS_SERVICE 228 value: "hdfs-namenode-service.default.domeos.sohu" 229 - name: HDFS_PORT 230 value: "4231" 231 - name: ZOOKEEPER_SERVICE_LIST 232 value: "zookeeper-1.default.domeos.sohu,zookeeper-2.default.domeos.sohu,zookeeper-3.default.domeos.sohu" 233 - name: ZOOKEEPER_PORT 234 value: "2181" 235 - name: ZNODE_PARENT 236 value: hbase 237 - name: HBASE_MASTER_LIST 238 value: "172.16.30.1:hbase-master-1 172.16.30.2:hbase-master-2" 239 - name: HBASE_REGION_LIST 240 value: "172.16.30.3:hbase-region-1" 241 restartPolicy: Always 242 nodeSelector: 243 kubernetes.io/hostname: bx-42-198
說明：該yaml文件共創建了兩個master服務、兩個regionserver服務，以及對應的兩個master Pods和兩個regionserver Pods；Pod的restartPolicy設為Always表示如果該Pod掛掉的話將一直嘗試重新啟動它；以環境變量的形式將參數傳遞進Pod中，其中HDFS_SERVICE為HDFS服務經過skyDNS之后的對應域名，若未設置skyDNS則此處值設為HDFS服務對應的IP地址，ZOOKEEPER_SERVICE_LIST同理；HBASE_MASTER_LIST的值格式為 <master服務IP地址>:<master對應Pod名>，多個項之間以空格分隔，HBASE_REGION_LIST同理。
接着就可以創建和查看HBase服務了：
# 創建 $kubectl create -f hbase.yaml service "hbase-master-1" created service "hbase-master-2" created service "hbase-region-1" created service "hbase-region-2" created pod "hbase-master-1" created pod "hbase-master-2" created pod "hbase-region-1" created pod "hbase-region-2" created # 查看pods $kubectl get pods NAME READY STATUS RESTARTS AGE hbase-master-1 1/1 Running 0 5s hbase-master-2 0/1 Pending 0 5s hbase-region-1 1/1 Running 0 5s hbase-region-2 0/1 Pending 0 5s hdfs-datanode-1-nek2l 1/1 Running 3 7d hdfs-datanode-2-vkbbt 1/1 Running 3 7d hdfs-datanode-3-h4jvt 1/1 Running 3 7d hdfs-namenode-1-cl0pj 1/1 Running 3 7d kube-dns-v8-x8igc 3/3 Running 0 4h zookeeper-1-ojhmy 1/1 Running 0 12h zookeeper-2-cr73i 1/1 Running 0 12h zookeeper-3-79ls0 1/1 Running 0 12h # 查看service $kubectl get service NAME CLUSTER_IP EXTERNAL_IP PORT(S) SELECTOR AGE hbase-master-1 172.16.30.1 <none> 60000/TCP,60001/TCP app=hbase-master,server-id=1 17m hbase-master-2 172.16.30.2 <none> 60000/TCP,60001/TCP app=hbase-master,server-id=2 17m hbase-region-1 172.16.30.3 <none> 60010/TCP,60011/TCP app=hbase-region,server-id=1 17m hbase-region-2 172.16.30.4 <none> 60010/TCP,60011/TCP app=hbase-region,server-id=2 17m hdfs-namenode-service 172.16.20.1 <none> 4231/TCP,50020/TCP,50090/TCP,50070/TCP,50010/TCP,50075/TCP,8031/TCP,8032/TCP,8033/TCP,8040/TCP,8042/TCP,49707/TCP,22/TCP,8088/TCP,8030/TCP app=hdfs-namenode 7d kube-dns 172.16.40.1 <none> 53/UDP,53/TCP app=kube-dns,version=v8 10h kubernetes 172.16.0.1 <none> 443/TCP <none> 12d zookeeper-1 172.16.11.1 <none> 2181/TCP,2888/TCP,3888/TCP name=zookeeper,server-id=1 13h zookeeper-2 172.16.11.2 <none> 2181/TCP,2888/TCP,3888/TCP name=zookeeper,server-id=2 13h zookeeper-3 172.16.11.3 <none> 2181/TCP,2888/TCP,3888/TCP name=zookeeper,server-id=3 13h
通過ZooKeeper的zkCli.sh可以看到/hbase下對應的master和rs的記錄（顯示亂碼是由於系統顯示時編碼的原因，無影響）：
[zk: localhost:2181(CONNECTED) 0] ls /hbase [meta-region-server, backup-masters, table, draining, region-in-transition, table-lock, running, master, namespace, hbaseid, online-snapshot, replication, splitWAL, recovering-regions, rs] [zk: localhost:2181(CONNECTED) 1] ls /hbase/rs [172.27.0.0,60010,1448896399329, 172.28.0.115,60010,1448896360650] [zk: localhost:2181(CONNECTED) 2] get /hbase/master ?master:60000??E*?O=PBUF base-master-1???????* cZxid = 0x100000186 ctime = Mon Nov 30 15:12:42 UTC 2015 mZxid = 0x100000186 mtime = Mon Nov 30 15:12:42 UTC 2015 pZxid = 0x100000186 cversion = 0 dataVersion = 0 aclVersion = 0 ephemeralOwner = 0x151563a5e37001a dataLength = 60 numChildren = 0
可以通過docker exec進入到HBase對應的容器中進行表操作以測試HBase的工作狀態：
# 進入198的hbase-master-2容器中 [@bx_42_198 /opt/scs/openxxs]# docker exec -it f131fcf15a72 /bin/bash # 使用hbase shell對hbase進行操作 [root@hbase-master-2 bin]# hbase shell 2015-11-30 15:15:58,632 INFO [main] Configuration.deprecation: hadoop.native.lib is deprecated. Instead, use io.native.lib.available HBase Shell; enter 'help<RETURN>' for list of supported commands. Type "exit<RETURN>" to leave the HBase Shell Version 0.98.10.1-hadoop2, rd5014b47660a58485a6bdd0776dea52114c7041e, Tue Feb 10 11:34:09 PST 2015 # 通過status查看狀態，這里顯示的 2 dead 是之前測試時遺留的記錄，無影響 hbase(main):001:0> status 2015-11-30 15:16:03,551 WARN [main] util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable 2 servers, 2 dead, 1.5000 average load # 創建表 hbase(main):002:0> create 'test','id','name' 0 row(s) in 0.8330 seconds => Hbase::Table - test # 查看表 hbase(main):003:0> list TABLE member test 2 row(s) in 0.0240 seconds => ["member", "test"] # 插入數據 hbase(main):004:0> put 'test','test1','id:5','addon' 0 row(s) in 0.1540 seconds # 查看數據 hbase(main):005:0> get 'test','test1' COLUMN CELL id:5 timestamp=1448906130803, value=addon 1 row(s) in 0.0490 seconds # 進入199的hbase-master-1容器中查看從198上插入的數據 hbase(main):001:0> get 'test','test1' 2015-11-30 18:01:23,944 WARN [main] util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable COLUMN CELL id:5 timestamp=1448906130803, value=addon 1 row(s) in 0.2430 seconds
從以上結果可以看出HBase算是在k8s中以不怎么完善的方式跑起來了。
六、討論
不得不維護/etc/hosts記錄的原因是HBase中master之間、regionserver之間、master與regionserver之間都是通過hostname來彼此識別對方的，而k8s的DNS只針對service並沒有對Pod進行解析。而如果把master和regionserver放在同一個Pod下的話存在磁盤資源共享沖突的問題（還沒仔細研究）。Github討論中下面的這段話很直白地說明了HBase對hostname的依賴：
1. Master uses ZooKeeper to run master election, the winner puts its hostname:port in ZooKeeper. 2. RegionServers will register themselves to the winning Master through its hostname registered in ZooKeeper. 3. We have a RegionServer with meta table/region (which stores Region -> RegionServer map), it stores its hostname:port in ZooKeeper. 4. When a client starts a request to HBase, it gets the hostname of the RegionServer with meta table from ZooKeeper, scan the meta table, and find out the hostname of the RegionServer it interests, and finally talks to the RegionServer through hostname.
為解決這個問題目前嘗試過的方法如下：
1. 配置skyDNS：skyDNS只針對service進行解析，無法解析Pod的名稱。如果向skyDNS中插入hostname的相關記錄並動態維護的話或許可以解決該問題，目前正在嘗試中。
2. 更改創建 ReplicationController、Server、Pod、Container 時的各種設置參數，如 name、generateName等，然並卵。
3. 創建container后啟動 master 前通過腳本更改 hostname：Docker只允許在Create Container時進行hostname的修改（docker run自身有一個hostname的參數可以指定Container的hostname），但在容器運行之后並不允許修改，修改則報如下錯誤：docker Error: hostname: you must be root to change the hostname. 這個錯誤有些誤導，事實上是docker的機制不允許你去修改hostname而不是權限問題，用root也沒法改。
4. 修改HBase參數使其上報到ZK中的值不是hostname而是IP地址：這個一度是前景光明的解決方案，但將hostname寫入ZK在HBase中是硬編碼在代碼中的，並沒有參數可以去設置此項。有人給出了個patch（戳這里），但測試結果並不好。
關於第五部分HBase部署方案的說明：選擇使用單Pod而不是ReplicationController，是因為k8s會在RC中Container的hostname后面加上隨機字符以區分彼此，而單Pod的Pod name和hostname是一致的；restartPolicy設為Always算是為單Pod方式魯棒性提供點小小的補償吧；如果將Pod name設置為對應service的IP或域名怎樣？然而hostname並不允許帶點號；寫入 /etc/hosts 中的IP選擇了service的而非Pod的，因為Pod中的IP在運行前並不能獲取到，而且在重啟Pod后也會發生改變，而service的IP是不變的，因此選擇了 serviceIP:PodName 這種對應關系。
最根本的解決方案是讓k8s支持hostname（或者說Pod）的DNS解析，前面配置ZooKeeper同樣存在hostname這個問題（戳這里），后面將要部署的Kafka也會有這個問題。k8s的開發團隊已經進行了許多討論並准備解決這個問題了（戳這里），希望下個版本會有相關設置。