zookeeper4-单机伪集群搭建

Zookeeper 集群模式:
Leader: 处理所有的事务请求(写请求),可以处理读请求,集群中只能有一个Leader
Follower:只能处理读请求,同时作为 Leader的候选节点,即如果Leader宕机,Follower节点
要参与到新的Leader选举中,有可能成为新的Leader节点。
Observer:只能处理读请求。不能参与选举

zookeeper4-单机伪集群搭建
文章图片

安裝步骤:
tar ‐zxvf apache‐zookeeper‐3.5.8‐bin.tar.gz
mv apache‐zookeeper‐3.5.8 zookeeper
cd zookeeper
cp conf/zoo_sample.cfg conf/zoo1.cfg
vim conf/zoo1.cfg
================
dataDir=/home/bzf/zookeeper/data/zookeeper1
clientPort=2181
server.1=192.168.25.111:2001:3001
server.2=192.168.25.111:2002:3002
server.3=192.168.25.111:2003:3003
server.4=192.168.25.111:2004:3004:observer
cd /home/bzf/zookeeper/data/zookeeper1
【zookeeper4-单机伪集群搭建】touch myid
echo 1 >> myid
======================
cp conf/zoo1.cfg conf/zoo2.cfg
vim conf/zoo2.cfg
dataDir=/home/bzf/zookeeper/data/zookeeper2
clientPort=2182
cd /home/bzf/zookeeper/data/zookeeper2
touch myid
echo 2 >> myid
====================
cp conf/zoo1.cfg conf/zoo3.cfg
vim conf/zoo3.cfg
dataDir=/home/bzf/zookeeper/data/zookeeper3
clientPort=2183
cd /home/bzf/zookeeper/data/zookeeper3
touch myid
echo 3 >> myid
==============
cp conf/zoo1.cfg conf/zoo4.cfg
vim conf/zoo4.cfg
dataDir=/home/bzf/zookeeper/data/zookeeper4
clientPort=2184
cd /home/bzf/zookeeper/data/zookeeper4
touch myid
echo 4 >> myid

分别启动四个节点
bin/zkServer.sh start conf/zoo1.cfg
bin/zkServer.sh start conf/zoo2.cfg
bin/zkServer.sh start conf/zoo3.cfg
bin/zkServer.sh start conf/zoo4.cfg

zookeeper4-单机伪集群搭建
文章图片

bin/zkServer.sh status conf/zoo1.cfg
bin/zkServer.sh status conf/zoo2.cfg
bin/zkServer.sh status conf/zoo3.cfg

二:通过源代码操作zk集群

@Slf4j public class MyCuratorClusterBaseOperations extends CuratorClusterBase {//测试集群:每隔5s从集群中获取一次数据,如果此时集群中的某个节点突然宕机,观察现象: //1.我们手动关闭2181的节点,发现服务没有报错仍然可以获取到数据 //2.我们手动关闭2181,2182节点,发现不能获取数据,集群失效 //3.我们手动启动2181节点,发现有能获取到数据 @Test public void testCluster() throws Exception { CuratorFramework curatorFramework = getCuratorFramework(); String pathWithParent = "/test"; byte[] bytes = curatorFramework.getData().forPath(pathWithParent); System.out.println(new String(bytes)); while (true) { try { byte[] bytes2 = curatorFramework.getData().forPath(pathWithParent); System.out.println(new String(bytes2)); TimeUnit.SECONDS.sleep(5); } catch (Exception e) { e.printStackTrace(); testCluster(); } } }//测试集群:每隔5s从集群中获取一次数据,如果此时集群中的某个节点突然宕机,观察现象: //1.我们手动关闭2181的节点,发现服务没有报错仍然可以获取到数据 //2.我们手动关闭2181,2182节点,发现不能获取数据,集群失效 //3.我们手动启动2181节点,发现有能获取到数据 public static void main(String[] args) throws Exception { RetryPolicy retryPolicy = new ExponentialBackoffRetry(5 * 1000, 10); String connectStr = "192.168.25.111:2181,192.168.25.111:2182,192.168.25.111:2183,192.168.25.111:2184"; CuratorFramework curatorFramework = CuratorFrameworkFactory.newClient(connectStr, retryPolicy); curatorFramework.start(); String pathWithParent = "/test"; byte[] bytes = curatorFramework.getData().forPath(pathWithParent); System.out.println(new String(bytes)); while (true) { try { byte[] bytes2 = curatorFramework.getData().forPath(pathWithParent); System.out.println(new String(bytes2)); TimeUnit.SECONDS.sleep(5); } catch (Exception e) { e.printStackTrace(); } } }}

    推荐阅读