使用Systemd运行Zookeeper 3.4.12和Solr 6.5.1 - Solr在启动后立即关闭

Question

我是一个相当新的系统和动物园管理员。请耐心等待，谢谢。任何帮助表示赞赏！

设置：

• Suse 12 Enterprise
• 没有init.d，只有systemd
• zookeeper 3.4.12通过systemd运行并侦听默认端口2181
• solr 6.5.1也必须通过systemd运行，但是在启动后立即solr决定关闭，原因不明
• solr.log显示建立连接到zookeeper以及警告和关闭后不久
• zookeeper logfile没有关于solr退出的单行

我很困惑，无法确定systemd单元文件或zookeeper < - > solr问题是否存在此问题。

问题：

• 单元文件solr.service是否正确？ （我不确定，网上的例子非常简陋）
• 这是systemd问题还是zookeeper问题？
• 我可以打开哪些日志以获得更多洞察力？

As @MatsLindh points out this is an sytemd issue. Solr log WARN was just a coincident.

journalctl -u solr

Sep 05 16:42:36 mucs75561 systemd[1]: Started Apache Solr Service.
Sep 05 16:42:40 mucs75561 solr[15732]: [98B blob data]
Sep 05 16:42:40 mucs75561 solr[15732]: Started Solr server on port 8983 
(pid=15857). Happy searching!
Sep 05 16:42:40 mucs75561 solr[15942]: Sending stop command to Solr running on port 8983 ... 
waiting up to 180 seconds to allow Jetty process 15857 to stop gracefully.

solr.log讲述了一个不同的故事（tail -n 1000 -f /opt/xxx/solr-6.5.1/server/logs/solr.log）

cat /opt/xxx/solr-6.5.1/server/logs/solr.log
16:42:38.594 INFO  (main) [   ] o.e.j.s.Server jetty-9.3.14.v20161028
16:42:38.992 INFO  (main) [   ] o.a.s.s.SolrDispatchFilter  ___      _       Welcome to Apache Solr™ version 6.5.1
16:42:38.996 INFO  (main) [   ] o.a.s.s.SolrDispatchFilter / __| ___| |_ _   Starting in cloud mode on port 8983
16:42:38.996 INFO  (main) [   ] o.a.s.s.SolrDispatchFilter \__ \/ _ \ | '_|  Install dir: /opt/xxx/solr-6.5.1
16:42:39.016 INFO  (main) [   ] o.a.s.s.SolrDispatchFilter |___/\___/_|_|    Start time: 2018-09-05T16:42:38.998Z
16:42:39.017 INFO  (main) [   ] o.a.s.s.StartupLoggingUtils Property solr.log.muteconsole given. Muting ConsoleAppender named CONSOLE
16:42:39.035 INFO  (main) [   ] o.a.s.c.SolrResourceLoader Using system property solr.solr.home: /opt/xxx/solr-6.5.1/server/solr
16:42:39.099 INFO  (main) [   ] o.a.s.s.SolrDispatchFilter Loading solr.xml from SolrHome (not found in ZooKeeper)
16:42:39.100 INFO  (main) [   ] o.a.s.c.SolrXmlConfig Loading container configuration from /opt/xxx/solr-6.5.1/server/solr/solr.xml
16:42:39.413 INFO  (main) [   ] o.a.s.u.UpdateShardHandler Creating UpdateShardHandler HTTP client with params: socketTimeout=600000&connTimeout=60000&retry=true
16:42:39.418 INFO  (main) [   ] o.a.s.c.ZkContainer Zookeeper client=localhost:2181/solr
16:42:39.510 INFO  (main) [   ] o.a.s.c.Overseer Overseer (id=null) closing
16:42:39.514 INFO  (main) [   ] o.a.s.c.OverseerElectionContext I am going to be the leader 192.168.18.49:8983_solr
16:42:39.519 INFO  (main) [   ] o.a.s.c.Overseer Overseer (id=72167078483197975-192.168.18.49:8983_solr-n_0000000009) starting
16:42:39.616 INFO  (main) [   ] o.a.s.c.ZkController Register node as live in ZooKeeper:/live_nodes/192.168.18.49:8983_solr
16:42:39.622 INFO  (OverseerStateUpdate-72167078483197975-192.168.18.49:8983_solr-n_0000000009) [   ] o.a.s.c.c.ZkStateReader Updated live nodes from ZooKeeper... (0) -> (1)
16:42:39.812 INFO  (main) [   ] o.a.s.c.CorePropertiesLocator Found 0 core definitions underneath /opt/xxx/solr-6.5.1/server/solr
16:42:39.898 INFO  (main) [   ] o.e.j.s.Server Started @1864ms
16:42:40.549 INFO  (ShutdownMonitor) [   ] o.a.s.c.CoreContainer Shutting down CoreContainer instance=966739377
16:42:40.557 INFO  (ShutdownMonitor) [   ] o.a.s.c.Overseer Overseer (id=72167078483197975-192.168.18.49:8983_solr-n_0000000009) closing
16:42:40.558 INFO  (OverseerStateUpdate-72167078483197975-192.168.18.49:8983_solr-n_0000000009) [   ] o.a.s.c.Overseer Overseer Loop exiting : 192.168.18.49:8983_solr
16:42:40.566 WARN  (zkCallback-5-thread-1-processing-n:192.168.18.49:8983_solr) [   ] o.a.s.c.c.ZkStateReader ZooKeeper watch triggered, but Solr cannot talk to ZK: [KeeperErrorCode = Session expired for /live_nodes]
16:42:40.566 INFO  (ShutdownMonitor) [   ] o.a.s.m.SolrMetricManager Closing metric reporters for: solr.node

我的/etc/systemd/system/solr.service：

[Unit]
Description=Apache Solr Service
After=syslog.target network.target nss-lookup.target
Requires=zookeeper.service

[Service]
User=xxx
Group=tomcat
WorkingDirectory=/opt/xxx/solr-6.5.1/
Environment=SOLR_INCLUDE=/opt/xxx/solr-6.5.1/bin/solr.in.sh   
ExecStart=/opt/xxx/solr-6.5.1/bin/solr start -m 4g -c -z localhost:2181/solr
ExecStop=/opt/xxx/solr-6.5.1/bin/solr stop -all

[Install]
WantedBy=default.target

谢谢阅读！

Answer 1

systemd requires the service that it starts继续运行。由于Solr启动脚本在启动Solr后退出（即它使进程守护并使其在后台运行），systemd认为它已经死了并试图阻止它。

您可以使用bin/solr start -f在前台启动solr：

-f            Start Solr in foreground; default starts Solr in the background
              and sends stdout / stderr to solr-PORT-console.log