使用带有 Boto 的 AWS EMR 安装引导错误

Question

随着 AMI 3.3.0 的发布，AWS 支持 Hue 作为 EMR 中的可安装“应用程序”，例如 Hive/Pig。使用 EMR Web UI，使用 Hue 创建集群对我来说效果很好，但是当通过 Boto 添加 Hue 安装引导操作时，我遇到了一个不确定的错误（它会定期崩溃）。我用相同的配置测试了 4 次，崩溃率为 50%。

在 Boto 中，我添加了一个额外的引导操作，在启用 Hue 时从 Web UI 创建集群时自动完成：

BootstrapAction('Install Hue', 's3://elasticmapreduce/libs/hue/install-hue', [])

集群然后终止：

Terminated with errors: On the master instance (i-c6b7582a), 
bootstrap action 2 returned a non-zero return code

在引导操作日志中：

Existing lock /var/run/yum.pid: another copy is running as pid 2007. Another app is currently holding the yum lock; waiting for it to exit... The other application is: yum Memory : 22 M RSS (305 MB VSZ) Started: Tue Nov 11 21:00:12 2014 - 00:19 ago State : Sleeping, pid: 2007 Another app is currently holding the yum lock; waiting for it to exit...

大量的，最后是一个大的堆栈跟踪：

Trying other mirror.
http://packages.ap-southeast-2.amazonaws.com/2014.09/main/20140901f63e/x86_64/repodata/repomd.xml?instance_id=i-c6b7582a&region=us-east-1: [Errno 12] Timeout on http://packages.ap-southeast-2.amazonaws.com/2014.09/main/20140901f63e/x86_64/repodata/repomd.xml?instance_id=i-c6b7582a&region=us-east-1: (28, 'Connection timed out after 10000 milliseconds')
Trying other mirror.
Traceback (most recent call last):
  File "/usr/bin/yum", line 29, in <module>
    yummain.user_main(sys.argv[1:], exit_code=True)
  File "/usr/share/yum-cli/yummain.py", line 355, in user_main
    errcode = main(args)
  File "/usr/share/yum-cli/yummain.py", line 174, in main
    result, resultmsgs = base.doCommands()
  File "/usr/share/yum-cli/cli.py", line 572, in doCommands
    return self.yum_cli_commands[self.basecmd].doCommand(self, self.basecmd, self.extcmds)
  File "/usr/share/yum-cli/yumcommands.py", line 432, in doCommand
    return base.installPkgs(extcmds, basecmd=basecmd)
  File "/usr/share/yum-cli/cli.py", line 968, in installPkgs
    txmbrs = self.install(pattern=arg)
  File "/usr/lib/python2.6/site-packages/yum/__init__.py", line 4721, in install
    mypkgs = self.pkgSack.returnPackages(patterns=pats,
  File "/usr/lib/python2.6/site-packages/yum/__init__.py", line 1069, in <lambda>
    pkgSack = property(fget=lambda self: self._getSacks(),
  File "/usr/lib/python2.6/site-packages/yum/__init__.py", line 774, in _getSacks
    self.repos.populateSack(which=repos)
  File "/usr/lib/python2.6/site-packages/yum/repos.py", line 383, in populateSack
    sack.populate(repo, mdtype, callback, cacheonly)
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 250, in populate
    if self._check_db_version(repo, mydbtype):
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 342, in _check_db_version
    return repo._check_db_version(mdtype)
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 1520, in _check_db_version
    repoXML = self.repoXML
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 1706, in <lambda>
    repoXML = property(fget=lambda self: self._getRepoXML(),
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 1702, in _getRepoXML
    self._loadRepoXML(text=self.ui_id)
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 1693, in _loadRepoXML
    return self._groupLoadRepoXML(text, self._mdpolicy2mdtypes())
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 1667, in _groupLoadRepoXML
    if self._commonLoadRepoXML(text):
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 1495, in _commonLoadRepoXML
    self._revertOldRepoXML()
  File "/usr/lib/python2.6/site-packages/yum/yumRepo.py", line 1345, in _revertOldRepoXML
    os.rename(old_data['old_local'], old_data['local'])
OSError: [Errno 2] No such file or directory

相比之下，引导日志在成功时显示一行：

Warning: RPMDB altered outside of yum.

Answer 1

在 EMR AMI 3.3 中安装和运行 Hue 的示例

import boto.emr
from boto.emr.emrobject import InstanceGroup
from boto.emr.bootstrap_action import BootstrapAction
from boto.emr.step import ScriptRunnerStep

conn = boto.emr.EmrConnection()

jobid = conn.run_jobflow(name="Hue Example", ami_version = "3.3.0",
                                log_uri="s3n://your-log-path-here",
                                instance_groups= get_instance_groups(),
                                bootstrap_actions=get_bootstrap_actions(),
                                ec2_keyname="your-ec2-key-name",
                                steps = get_startup_steps()
                                )

def get_bootstrap_actions():
    install_hue_action = BootstrapAction("Install Hue ",
                                "s3n://us-east-1.elasticmapreduce/libs/hue/install-hue",
                                bootstrap_action_args=None)
    return [install_hue_action]


def get_startup_steps():
    runHueStep = ScriptRunnerStep(name="Run Hue",
                                        step_args = ["s3n://us-east-1.elasticmapreduce/libs/hue/run-hue"])
    return [runHueStep]


def get_instance_groups():
    #This is just an example. Actual implementation will have core, and task instance groups as well. Please choose your instance type, number, and bid price wisely as might it get too expensive too quickly.
    spotInstanceGroup =  InstanceGroup()
    spotInstanceGroup.name="Spot Instance Group Master"
    spotInstanceGroup.bidprice="0.20"
    spotInstanceGroup.num_instances = 1
    spotInstanceGroup.market="SPOT"
    spotInstanceGroup.type="c3.2xlarge"
    spotInstanceGroup.role="MASTER"