1. [hadoop@test ~]$ start-dfs.sh 
    2. [Fatal Error] mapred-site.xml:7:2: The markup in the document following the root element must be well-formed.
    3. 20/04/27 22:02:09 FATAL conf.Configuration: error parsing conf mapred-site.xml
    4. org.xml.sax.SAXParseException; systemId: file:/opt/hadoop-2.7.6/etc/hadoop/mapred-site.xml; lineNumber: 7; columnNumber: 2; The markup in the document following the root element must be well-formed.
    5.     at org.apache.xerces.parsers.DOMParser.parse(Unknown Source)
    6.     at org.apache.xerces.jaxp.DocumentBuilderImpl.parse(Unknown Source)
    7.     at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:150)
    8.     at org.apache.hadoop.conf.Configuration.parse(Configuration.java:2552)
    9.     at org.apache.hadoop.conf.Configuration.parse(Configuration.java:2540)
    10.     at org.apache.hadoop.conf.Configuration.loadResource(Configuration.java:2614)
    11.     at org.apache.hadoop.conf.Configuration.loadResources(Configuration.java:2564)
    12.     at org.apache.hadoop.conf.Configuration.getProps(Configuration.java:2477)
    13.     at org.apache.hadoop.conf.Configuration.get(Configuration.java:1047)
    14.     at org.apache.hadoop.conf.Configuration.getTrimmed(Configuration.java:1101)
    15.     at org.apache.hadoop.conf.Configuration.getLong(Configuration.java:1374)
    16.     at org.apache.hadoop.security.Groups.<init>(Groups.java:111)
    17.     at org.apache.hadoop.security.Groups.<init>(Groups.java:99)
    18.     at org.apache.hadoop.security.Groups.getUserToGroupsMappingService(Groups.java:434)
    19.     at org.apache.hadoop.security.UserGroupInformation.initialize(UserGroupInformation.java:284)
    20.     at org.apache.hadoop.security.UserGroupInformation.ensureInitialized(UserGroupInformation.java:261)
    21.     at org.apache.hadoop.security.UserGroupInformation.loginUserFromSubject(UserGroupInformation.java:806)
    22.     at org.apache.hadoop.security.UserGroupInformation.getLoginUser(UserGroupInformation.java:776)
    23.     at org.apache.hadoop.security.UserGroupInformation.getCurrentUser(UserGroupInformation.java:649)
    24.     at org.apache.hadoop.hdfs.tools.GetConf.run(GetConf.java:315)
    25.     at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
    26.     at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:84)
    27.     at org.apache.hadoop.hdfs.tools.GetConf.main(GetConf.java:332)
    28. Exception in thread "main" java.lang.RuntimeException: org.xml.sax.SAXParseException; systemId: file:/opt/hadoop-2.7.6/etc/hadoop/mapred-site.xml; lineNumber: 7; columnNumber: 2; The markup in the document following the root element must be well-formed.
    29.     at org.apache.hadoop.conf.Configuration.loadResource(Configuration.java:2728)
    30.     at org.apache.hadoop.conf.Configuration.loadResources(Configuration.java:2564)
    31.     at org.apache.hadoop.conf.Configuration.getProps(Configuration.java:2477)
    32.     at org.apache.hadoop.conf.Configuration.get(Configuration.java:1047)
    33.     at org.apache.hadoop.conf.Configuration.getTrimmed(Configuration.java:1101)
    34.     at org.apache.hadoop.conf.Configuration.getLong(Configuration.java:1374)
    35.     at org.apache.hadoop.security.Groups.<init>(Groups.java:111)
    36.     at org.apache.hadoop.security.Groups.<init>(Groups.java:99)
    37.     at org.apache.hadoop.security.Groups.getUserToGroupsMappingService(Groups.java:434)
    38.     at org.apache.hadoop.security.UserGroupInformation.initialize(UserGroupInformation.java:284)
    39.     at org.apache.hadoop.security.UserGroupInformation.ensureInitialized(UserGroupInformation.java:261)
    40.     at org.apache.hadoop.security.UserGroupInformation.loginUserFromSubject(UserGroupInformation.java:806)
    41.     at org.apache.hadoop.security.UserGroupInformation.getLoginUser(UserGroupInformation.java:776)
    42.     at org.apache.hadoop.security.UserGroupInformation.getCurrentUser(UserGroupInformation.java:649)
    43.     at org.apache.hadoop.hdfs.tools.GetConf.run(GetConf.java:315)
    44.     at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
    45.     at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:84)
    46.     at org.apache.hadoop.hdfs.tools.GetConf.main(GetConf.java:332)
    47. Caused by: org.xml.sax.SAXParseException; systemId: file:/opt/hadoop-2.7.6/etc/hadoop/mapred-site.xml; lineNumber: 7; columnNumber: 2; The markup in the document following the root element must be well-formed.
    48.     at org.apache.xerces.parsers.DOMParser.parse(Unknown Source)
    49.     at org.apache.xerces.jaxp.DocumentBuilderImpl.parse(Unknown Source)
    50.     at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:150)
    51.     at org.apache.hadoop.conf.Configuration.parse(Configuration.java:2552)
    52.     at org.apache.hadoop.conf.Configuration.parse(Configuration.java:2540)
    53.     at org.apache.hadoop.conf.Configuration.loadResource(Configuration.java:2614)
    54.     ... 17 more
    55. Starting namenodes on []
    56. test: starting namenode, logging to /opt/hadoop-2.7.6/logs/hadoop-hadoop-namenode-test.out
    57. test: [Fatal Error] mapred-site.xml:7:2: The markup in the document following the root element must be well-formed.
    58. test: starting datanode, logging to /opt/hadoop-2.7.6/logs/hadoop-hadoop-datanode-test.out
    59. test: [Fatal Error] mapred-site.xml:7:2: The markup in the document following the root element must be well-formed.
    60. [Fatal Error] mapred-site.xml:7:2: The markup in the document following the root element must be well-formed.
    61. 20/04/27 22:02:20 FATAL conf.Configuration: error parsing conf mapred-site.xml
    62. org.xml.sax.SAXParseException; systemId: file:/opt/hadoop-2.7.6/etc/hadoop/mapred-site.xml; lineNumber: 7; columnNumber: 2; The markup in the document following the root element must be well-formed.
    63.     at org.apache.xerces.parsers.DOMParser.parse(Unknown Source)
    64.     at org.apache.xerces.jaxp.DocumentBuilderImpl.parse(Unknown Source)
    65.     at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:150)
    66.     at org.apache.hadoop.conf.Configuration.parse(Configuration.java:2552)
    67.     at org.apache.hadoop.conf.Configuration.parse(Configuration.java:2540)
    68.     at org.apache.hadoop.conf.Configuration.loadResource(Configuration.java:2614)
    69.     at org.apache.hadoop.conf.Configuration.loadResources(Configuration.java:2564)
    70.     at org.apache.hadoop.conf.Configuration.getProps(Configuration.java:2477)
    71.     at org.apache.hadoop.conf.Configuration.get(Configuration.java:1047)
    72.     at org.apache.hadoop.conf.Configuration.getTrimmed(Configuration.java:1101)
    73.     at org.apache.hadoop.conf.Configuration.getLong(Configuration.java:1374)
    74.     at org.apache.hadoop.security.Groups.<init>(Groups.java:111)
    75.     at org.apache.hadoop.security.Groups.<init>(Groups.java:99)
    76.     at org.apache.hadoop.security.Groups.getUserToGroupsMappingService(Groups.java:434)
    77.     at org.apache.hadoop.security.UserGroupInformation.initialize(UserGroupInformation.java:284)
    78.     at org.apache.hadoop.security.UserGroupInformation.ensureInitialized(UserGroupInformation.java:261)
    79.     at org.apache.hadoop.security.UserGroupInformation.loginUserFromSubject(UserGroupInformation.java:806)
    80.     at org.apache.hadoop.security.UserGroupInformation.getLoginUser(UserGroupInformation.java:776)
    81.     at org.apache.hadoop.security.UserGroupInformation.getCurrentUser(UserGroupInformation.java:649)
    82.     at org.apache.hadoop.hdfs.tools.GetConf.run(GetConf.java:315)
    83.     at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
    84.     at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:84)
    85.     at org.apache.hadoop.hdfs.tools.GetConf.main(GetConf.java:332)
    86. Exception in thread "main" java.lang.RuntimeException: org.xml.sax.SAXParseException; systemId: file:/opt/hadoop-2.7.6/etc/hadoop/mapred-site.xml; lineNumber: 7; columnNumber: 2; The markup in the document following the root element must be well-formed.
    87.     at org.apache.hadoop.conf.Configuration.loadResource(Configuration.java:2728)
    88.     at org.apache.hadoop.conf.Configuration.loadResources(Configuration.java:2564)
    89.     at org.apache.hadoop.conf.Configuration.getProps(Configuration.java:2477)
    90.     at org.apache.hadoop.conf.Configuration.get(Configuration.java:1047)
    91.     at org.apache.hadoop.conf.Configuration.getTrimmed(Configuration.java:1101)
    92.     at org.apache.hadoop.conf.Configuration.getLong(Configuration.java:1374)
    93.     at org.apache.hadoop.security.Groups.<init>(Groups.java:111)
    94.     at org.apache.hadoop.security.Groups.<init>(Groups.java:99)
    95.     at org.apache.hadoop.security.Groups.getUserToGroupsMappingService(Groups.java:434)
    96.     at org.apache.hadoop.security.UserGroupInformation.initialize(UserGroupInformation.java:284)
    97.     at org.apache.hadoop.security.UserGroupInformation.ensureInitialized(UserGroupInformation.java:261)
    98.     at org.apache.hadoop.security.UserGroupInformation.loginUserFromSubject(UserGroupInformation.java:806)
    99.     at org.apache.hadoop.security.UserGroupInformation.getLoginUser(UserGroupInformation.java:776)
    100.     at org.apache.hadoop.security.UserGroupInformation.getCurrentUser(UserGroupInformation.java:649)
    101.     at org.apache.hadoop.hdfs.tools.GetConf.run(GetConf.java:315)
    102.     at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:70)
    103.     at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:84)
    104.     at org.apache.hadoop.hdfs.tools.GetConf.main(GetConf.java:332)
    105. Caused by: org.xml.sax.SAXParseException; systemId: file:/opt/hadoop-2.7.6/etc/hadoop/mapred-site.xml; lineNumber: 7; columnNumber: 2; The markup in the document following the root element must be well-formed.
    106.     at org.apache.xerces.parsers.DOMParser.parse(Unknown Source)
    107.     at org.apache.xerces.jaxp.DocumentBuilderImpl.parse(Unknown Source)
    108.     at javax.xml.parsers.DocumentBuilder.parse(DocumentBuilder.java:150)
    109.     at org.apache.hadoop.conf.Configuration.parse(Configuration.java:2552)
    110.     at org.apache.hadoop.conf.Configuration.parse(Configuration.java:2540)
    111.     at org.apache.hadoop.conf.Configuration.loadResource(Configuration.java:2614)
    112.     ... 17 more

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