ubuntu - 为什么 Elasticsearch 在 Ubuntu 16.04 上是手动启动而不是作为服务启动？

Question

我在运行 Ubuntu 16.04 LTS 的 ARM Odroid XU4 上安装了 ELasticsearch 6 和 JDK 1.8.0_161。没有错误。

当我尝试将 Elasticsearch 作为服务启动时，我无法连接到端口 9200 上的本地主机并且服务状态打印:

~ $ > sudo service elasticsearch status
● elasticsearch.service - LSB: Starts elasticsearch
   Loaded: loaded (/etc/init.d/elasticsearch; bad; vendor preset: enabled)
   Active: active (exited) since Mon 2018-01-22 10:43:18 UTC; 9min ago
     Docs: man:systemd-sysv-generator(8)

Jan 22 10:43:18 lego systemd[1]: Starting LSB: Starts elasticsearch...
Jan 22 10:43:18 lego systemd[1]: Started LSB: Starts elasticsearch.
Jan 22 10:44:07 lego systemd[1]: Started LSB: Starts elasticsearch.

没有日志。不知道去哪里看。 /etc/security/limits.conf 中的 nofile 限制设置为 65536。我不知道还能去哪里寻找诊断。

虽然，当我通过 sudo/usr/shared/elasticsearch/bin/elasticsearch 手动启动 Elasticsearch 时，它按预期工作:

~ $ > sudo /usr/share/elasticsearch/bin/elasticsearch
[2018-01-22 10:55:55,944][WARN ][bootstrap                ] jvm uses the client vm, make sure to run `java` with the server vm for best performance by adding `-server` to the command line
[2018-01-22 10:55:56,073][INFO ][node                     ] [Ariel] version[1.7.3], pid[1126], build[NA/NA]
[2018-01-22 10:55:56,074][INFO ][node                     ] [Ariel] initializing ...
[2018-01-22 10:55:56,521][INFO ][plugins                  ] [Ariel] loaded [], sites []
[2018-01-22 10:55:56,638][INFO ][env                      ] [Ariel] using [1] data paths, mounts [[/ (/dev/mmcblk0p2)]], net usable_space 
[54.4gb], net total_space [57.2gb], types [ext4]
[2018-01-22 10:56:01,853][INFO ][node                     ] [Ariel] initialized
[2018-01-22 10:56:01,854][INFO ][node                     ] [Ariel] starting ...
[2018-01-22 10:56:02,080][INFO ][transport                ] [Ariel] bound_address {inet[/0:0:0:0:0:0:0:0:9300]}, publish_address {inet[/192.168.0.103:9300]}
[2018-01-22 10:56:02,125][INFO ][discovery                ] [Ariel] elasticsearch/FtFOljAORnevIAOAFabptg
[2018-01-22 10:56:05,933][INFO ][cluster.service          ] [Ariel] new_master [Ariel][FtFOljAORnevIAOAFabptg][lego]
[inet[/192.168.0.103:9300]], reason: zen-disco-join (elected_as_master)
[2018-01-22 10:56:05,987][INFO ][http                     ] [Ariel] bound_address {inet[/0:0:0:0:0:0:0:0:9200]}, publish_address {inet[/192.168.0.103:9200]}
[2018-01-22 10:56:05,988][INFO ][node                     ] [Ariel] started
[2018-01-22 10:56:06,014][INFO ][gateway                  ] [Ariel] 
recovered [0] indices into cluster_state

我错过了什么重要的步骤？我关注这里的一切:https://www.elastic.co/guide/en/elasticsearch/reference/current/deb.html

编辑:我尝试在 /etc/default/elasticsearch 中设置 START_DAEMON=true，这 确实很重要，但是没有用绝招。深入查看 /etc/default/elasticsearch 中设置的值，我发现了我的问题。请参阅我的最终答案以了解完整的解决方案。

Answer 1

正如@Suaro 所述:我们的问题与 this question with nearly identical symptoms 中讨论的内容有关和 this thread that reiterates the START_DAEMON solution在第一个链接中。这是一个好的开始，但对我来说并没有提供全面的解决方案。我更深入地研究了权限、堆大小和所有权，以找到最终解决方案。

这些是根据 Elasticsearch debian installation instructions 在 Ubuntu 16.04 上安装 Elasticsearch 6 的步骤截至 2018 年 1 月:

1. 在 /etc/default/elasticsearch 中设置 START_DAEMON=true 并重启服务。
2. 如果系统有 2GB RAM(在我的例子中是这样)，设置 ES_HEAP_SIZE=1g
3. 检查/usr/share/elasticsearch中elasticsearch目录的权限。 root 可能拥有这些，这不理想。 如果您还不知道，以根用户身份运行任何服务都会使您的基础设施暴露给攻击者利用。
4. #3 中的诱惑是设置 ES_USER=root 和 ES_GROUP=root 这将解决您的问题。 Elasticsearch 将作为一项服务启动(尽管他们的产品文档声称 ES 不会作为 root 运行)。 不要那样做。

5. 相反，检查本地是否存在 elasticsearch 用户以及同名组是否也存在。

   $ cut -d: -f1 /etc/passwd
   $ cut -d: -f1 /etc/group
   

6. 然后，将所有 elasticsearch 文件夹和资源的所有权更改为 elasticsearch 用户和组。

   $ ~ $ > ll /usr/share/elasticsearch/
   total 8.0K
   drwxr-xr-x 2 elasticsearch 4.0K Jan 22 10:02 bin/
   lrwxrwxrwx 1 elasticsearch   18 Dec 24  2015 config -> /etc/elasticsearch/
   lrwxrwxrwx 1 elasticsearch   22 Dec 24  2015 data -> /var/lib/elasticsearch/
   lrwxrwxrwx 1 elasticsearch   22 Dec 24  2015 logs -> /var/log/elasticsearch/
   drwxr-xr-x 2 elasticsearch 4.0K Dec 24  2015 plugins/
   
   # ^-- Take note that the symlinked directories need to be adjusted too
   
   $ sudo chown -R elasticsearch:elasticsearch /usr/share/elasticsearch
   $ sudo chown -R elasticsearch:elasticsearch /etc/elasticsearch/
   $ sudo chown -R elasticsearch:elasticsearch /var/lib/elasticsearch/
   $ sudo chown -R elasticsearch:elasticsearch /var/log/elasticsearch/
   

7. 然后，在 /etc/default/elasticsearch 中设置值 ES_USER=elasticsearch 和 ES_GROUP=elasticsearch 如果它们不是不要已经这样设置了(以防你屈服于 #4 的诱惑)。

8. 再试一次...

   ~ $ > sudo service elasticsearch status
   ● elasticsearch.service - LSB: Starts elasticsearch
      Loaded: loaded (/etc/init.d/elasticsearch; bad; vendor preset: enabled)
      Active: active (exited) since Mon 2018-01-22 20:51:29 UTC; 2min 25s ago
        Docs: man:systemd-sysv-generator(8)
     Process: 3133 ExecStop=/etc/init.d/elasticsearch stop (code=exited, status=0/SUCCESS)
     Process: 3209 ExecStart=/etc/init.d/elasticsearch start (code=exited, status=0/SUCCESS)
   
   ~ $ > sudo systemctl restart elasticsearch.service
   
   ~ $ > sudo service elasticsearch status
   ● elasticsearch.service - LSB: Starts elasticsearch
      Loaded: loaded (/etc/init.d/elasticsearch; bad; vendor preset: enabled)
      Active: active (running) since Mon 2018-01-22 20:54:05 UTC; 2s ago
        Docs: man:systemd-sysv-generator(8)
     Process: 3306 ExecStop=/etc/init.d/elasticsearch stop (code=exited, status=0/SUCCESS)
     Process: 3340 ExecStart=/etc/init.d/elasticsearch start (code=exited, status=0/SUCCESS)
      CGroup: /system.slice/elasticsearch.service
              └─3391 /usr/lib/jvm/java-8-openjdk-armhf/bin/java -Xms1g -Xmx1g -Djava.awt.headless=true -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:CMSInitiatingOccupancyFraction=75 -XX:+UseCMSInitiatingOccupancyOnly -XX:+HeapDumpOnOutOfMemoryError -XX:+DisableExplicitGC -Dfile.encoding=UTF-8 -Delasticsearch -Des.pidfil
   
   Jan 22 20:54:04 lego systemd[1]: Starting LSB: Starts elasticsearch...
   Jan 22 20:54:05 lego elasticsearch[3340]:  * Starting Elasticsearch Server
   Jan 22 20:54:05 lego elasticsearch[3340]:    ...done.
   Jan 22 20:54:05 lego systemd[1]: Started LSB: Starts elasticsearch.
   Jan 22 20:51:29 lego systemd[1]: Starting LSB: Starts elasticsearch...
   

中提琴!

~ $ > curl -XGET 'localhost:9200/?pretty'
{
  "status" : 200,
  "name" : "Svarog",
  "cluster_name" : "elasticsearch",
  "version" : {
    "number" : "1.7.3",
    "build_hash" : "NA",
    "build_timestamp" : "NA",
    "build_snapshot" : false,
    "lucene_version" : "4.10.4"
  },
  "tagline" : "You Know, for Search"
}