linux - ansible 启动进程，如果没有使用 ps 运行

Question

我正在使用 ansible 启动 namenode 进程，如果它没有运行，我正在使用 jps 检查进程并使用 service_namenode_status 检查状态并启动使用 service_namenode_start 的过程知道如何正确使用它吗...？

  - name: Check if Namenode is running
    shell: jps | grep " NameNode" | grep -v grep
    ignore_errors: yes
    changed_when: false
    register: service_namenode_status

  - name: Report status of Namenode
    fail:
      msg: |
        Service NameNode is not running.
        Return code from `jps | grep " NameNode" | grep -v grep`:
        {{ service_namenode_status.rc }}
    when: service_namenode_status.rc != 0
    register: service_namenode_start

  - name: Start Namenode
    command: su - hdfs -c "/usr/hdp/current/hadoop-client/sbin/hadoop-daemon.sh --config $HADOOP_CONF_DIR start namenode"
    tags: namenode
    when: service_namenode_status.rc != 0

输出:

TASK [namenode : Check if Namenode is running] *********************************
fatal: [server1.hdp.vagrant.data.uc]: FAILED! => {"changed": false, "cmd": "jps | grep \" NameNode\" | grep -v grep", "delta": "0:00:00.192755", "end": "2016-11-09 10:59:10.360552", "failed": true, "rc": 1, "start": "2016-11-09 10:59:10.167797", "stderr": "", "stdout": "", "stdout_lines": [], "warnings": []}
...ignoring

TASK [namenode : Report status of Namenode] ************************************
fatal: [server1.hdp.vagrant.data.uc]: FAILED! => {"changed": false, "failed": true, "msg": "Service NameNode is not running.\nReturn code from `jps | grep \" NameNode\" | grep -v grep`:\n1  \n"}

NO MORE HOSTS LEFT *************************************************************

RUNNING HANDLER [metastore : restart postgresql] *******************************
    to retry, use: --limit @/Users/krisdigitx/myLab/hdp/provisioning/site.retry

PLAY RECAP *********************************************************************
server1.hdp.vagrant.data.uc : ok=86   changed=32   unreachable=0    failed=1

Ansible failed to complete successfully. Any error output should be
visible above. Please fix these errors and try again.

Answer 1

试试这个:

- name: Check if Namenode is running
  tags: namenode
  shell: jps | grep " NameNode" | grep -v grep
  ignore_errors: yes
  changed_when: false
  register: service_namenode_status

- name: Start Namenode
  tags: namenode
  command: su - hdfs -c "/usr/hdp/current/hadoop-client/sbin/hadoop-daemon.sh --config $HADOOP_CONF_DIR start namenode"
  when: service_namenode_status.rc == 1

我的改变是:

1. 我在第一部分添加了“tags: namenode”行；如果要过滤此标签，则需要收集寄存器值

2. 我删除了您的第 2 部分并直接进入第 3 部分。

类似的配置正在为我解决类似的问题。