我正在尝试运行 Mrjob example 来 self 笔记本电脑上的 Hadoop with Python 一书，采用伪分布式模式。

(文件salaries.csv可以找到here)

所以我可以启动名称节点和数据节点:

start-dfs.sh

返回:

Starting namenodes on [localhost]
localhost: starting namenode, logging to /home/me/hadoop-2.7.3/logs/hadoop-me-namenode-me-Notebook-PC.out
localhost: starting datanode, logging to /home/me/hadoop-2.7.3/logs/hadoop-me-datanode-me-Notebook-PC.out
Starting secondary namenodes [0.0.0.0]
0.0.0.0: starting secondarynamenode, logging to /home/me/hadoop-2.7.3/logs/hadoop-me-secondarynamenode-me-Notebook-PC.out

我也没有问题创建输入文件结构和复制 salaries.csv 到 hdfs:

hdfs dfs -mkdir /user/
hdfs dfs -mkdir /user/me/
hdfs dfs -mkdir /user/me/input/
hdfs dfs -put /home/me/Desktop/work/cv/hadoop/salaries.csv /user/me/input/
hdfs dfs -ls /user/me/input/

返回:

Found 1 items
-rw-r--r--   3 me supergroup    1771685 2016-12-24 15:57 /user/me/input/salaries.csv

我还使 top_salaries.py 可执行:

sudo chmod a+x /home/me/Desktop/work/cv/hadoop/top_salaries.py

在本地模式下启动 top_salaries.py 也可以:

python2 top_salaries.py -r local salaries.csv > answer.csv

返回:

No configs found; falling back on auto-configuration
Creating temp directory /tmp/top_salaries.me.20161224.195052.762894
Running step 1 of 1...
Counters: 1
    warn
        missing gross=3223
Counters: 1
    warn
        missing gross=3223
Streaming final output from /tmp/top_salaries.me.20161224.195052.762894/output...
Removing temp directory /tmp/top_salaries.me.20161224.195052.762894...

但是，在 hadoop 上运行此作业(将它们放在一起)python2 top_salaries.py -r hadoop hdfs:///user/me/input/salaries.csv 返回:

No configs found; falling back on auto-configuration
Looking for hadoop binary in $PATH...
Found hadoop binary: /home/me/hadoop-2.7.3/bin/hadoop
Using Hadoop version 2.7.3
Looking for Hadoop streaming jar in /home/me/hadoop-2.7.3...
Found Hadoop streaming jar: /home/me/hadoop-2.7.3/share/hadoop/tools/lib/hadoop-streaming-2.7.3.jar
Creating temp directory /tmp/top_salaries.me.20161224.195201.967990
Copying local files to hdfs:///user/me/tmp/mrjob/top_salaries.me.20161224.195201.967990/files/...
Running step 1 of 1...
  session.id is deprecated. Instead, use dfs.metrics.session-id
  Initializing JVM Metrics with processName=JobTracker, sessionId=
  Cannot initialize JVM Metrics with processName=JobTracker, sessionId= - already initialized
  Cleaning up the staging area file:/tmp/hadoop-me/mapred/staging/me553683497/.staging/job_local553683497_0001
  Error launching job , bad input path : File does not exist: /tmp/hadoop-me/mapred/staging/me553683497/.staging/job_local553683497_0001/files/mrjob.zip#mrjob.zip
  Streaming Command Failed!
Attempting to fetch counters from logs...
Can't fetch history log; missing job ID
No counters found
Scanning logs for probable cause of failure...
Can't fetch history log; missing job ID
Can't fetch task logs; missing application ID
Step 1 of 1 failed: Command '['/home/me/hadoop-2.7.3/bin/hadoop', 'jar', '/home/me/hadoop-2.7.3/share/hadoop/tools/lib/hadoop-streaming-2.7.3.jar', '-files', 'hdfs:///user/me/tmp/mrjob/top_salaries.me.20161224.195201.967990/files/mrjob.zip#mrjob.zip,hdfs:///user/me/tmp/mrjob/top_salaries.me.20161224.195201.967990/files/setup-wrapper.sh#setup-wrapper.sh,hdfs:///user/me/tmp/mrjob/top_salaries.me.20161224.195201.967990/files/top_salaries.py#top_salaries.py', '-input', 'hdfs:///user/me/input/salaries.csv', '-output', 'hdfs:///user/me/tmp/mrjob/top_salaries.me.20161224.195201.967990/output', '-mapper', 'sh -ex setup-wrapper.sh python top_salaries.py --step-num=0 --mapper', '-combiner', 'sh -ex setup-wrapper.sh python top_salaries.py --step-num=0 --combiner', '-reducer', 'sh -ex setup-wrapper.sh python top_salaries.py --step-num=0 --reducer']' returned non-zero exit status 512

编辑:

这是我的 core-site.xml:

<configuration>
 <property>         
    <name>fs.defaultFS</name>         
    <value>hdfs://localhost:9000</value>    
 </property>
</configuration>

这是我的 hdfs-site.xml:

<configuration>
    <property>
       <name>dfs.namenode.name.dir</name>
       <value>/home/me/Desktop/work/cv/hadoop/namenode</value>
    </property>
    <property>
       <name>dfs.datanode.data.dir</name>
       <value>/home/me/Desktop/work/cv/hadoop/datanode</value>
    </property>
</configuration>

(其他 xml 配置文件，我没有编辑/更改)

编辑2:

这是 python 脚本(与上面的 github 链接相同)

from mrjob.job import MRJob
from mrjob.step import MRStep
import csv

cols = 'Name,JobTitle,AgencyID,Agency,HireDate,AnnualSalary,GrossPay'.split(',')

class salarymax(MRJob):

    def mapper(self, _, line):
        # Convert each line into a dictionary
        row = dict(zip(cols, [ a.strip() for a in csv.reader([line]).next()]))

        # Yield the salary
        yield 'salary', (float(row['AnnualSalary'][1:]), line)

        # Yield the gross pay
        try:
            yield 'gross', (float(row['GrossPay'][1:]), line)
        except ValueError:
            self.increment_counter('warn', 'missing gross', 1)

    def reducer(self, key, values):
        topten = []

        # For 'salary' and 'gross' compute the top 10
        for p in values:
            topten.append(p)
            topten.sort()
            topten = topten[-10:]

        for p in topten:
            yield key, p

    combiner = reducer

if __name__ == '__main__':
salarymax.run()

最佳答案

Ok .您需要编辑文件 core-site.xml:

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
    <property>
        <name>fs.default.name</name>
        <value>hdfs://master:9000</value>
    </property>
</configuration>

和文件 hdfs-site.xml 为:

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
    <property>
        <name>dfs.replication</name>
        <value>2</value>
    </property>
    <property>
        <name>dfs.permissions</name>
        <value>false</value>
    </property>
    <property>
        <name>dfs.namenode.name.dir</name>
        <value>/home/edureka/hadoop-2.7.3/namenode</value>
    </property>
    <property>
        <name>dfs.datanode.data.dir</name>
        <value>/home/edureka/hadoop-2.7.3/datanode</value>
    </property>
</configuration>

并且您需要将 hdfs-site.xml 编辑为:

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
    <property>
        <name>dfs.replication</name>
        <value>2</value>
    </property>
    <property>
        <name>dfs.permissions</name>
        <value>false</value>
    </property>
    <property>
        <name>dfs.datanode.data.dir</name>
        <value>/home/edureka/hadoop-2.7.3/datanode</value>
    </property>
</configuration>

并且您需要创建一个包含以下内容的mapred-site.xml 文件:

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
    <property>
        <name>mapreduce.framework.name</name>
        <value>yarn</value>
    </property>
</configuration>

并且您需要编辑 yarn-site.xml 以包含:

<?xml version="1.0" encoding="UTF-8"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
    <property>
        <name>yarn.nodemanager.aux-services</name>
        <value>mapreduce_shuffle</value>
    </property>
    <property>
        <name>yarn.nodemanager.auxservices.mapreduce.shuffle.class</name>
        <value>org.apache.hadoop.mapred.ShuffleHandler</value>
    </property>
</configuration>

然后做:

start-dfs.sh
start-yarn.sh

然后做:

hdfs dfs -mkdir /user/
hdfs dfs -mkdir /user/me/
hdfs dfs -mkdir /user/me/input/
hdfs dfs -put /home/me/Desktop/work/cv/hadoop/salaries.csv /user/me/input/

现在正在做:

sudo chmod a+x /home/me/Desktop/work/cv/hadoop/top_salaries.py
python2 top_salaries.py -r hadoop  hdfs:///user/me/input/salaries.csv > answer.csv

有效。

关于python - Hadoop 模式下的 Mrjob : Error launching job , 输入路径错误:文件不存在，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/41314376/