我正在尝试在新的CentOS 7虚拟机上安装tomcat。我成功安装了apache httpd，并且在网络中另一台计算机上的网络浏览器中键入虚拟机的ip时能够获得apache测试页。但是当我键入时，我收到以下错误消息systemctl start tomcat：
Job for tomcat.service failed. See 'systemctl status tomcat.service' and 'journalctl -xn' for details.
这是安装Java和tomcat的命令的完整历史记录：
我首先使用本教程中的指令安装Java ，因为tomcat指令（下面的第二个块）希望我使用openjdk，并且我需要使用真正的Java：
//Install Java
# cd /opt/
# yum install wget
# wget --no-cookies --no-check-certificate --header "Cookie: gpw_e24=http%3A%2F%2Fwww.oracle.com%2F; oraclelicense=accept-securebackup-cookie" "http://download.oracle.com/otn-pub/java/jdk/8u60-b27/jdk-8u60-linux-x64.tar.gz"
# tar xzf jdk-8u60-linux-x64.tar.gz
# cd /opt/jdk1.8.0_60/
# alternatives --install /usr/bin/java java /opt/jdk1.8.0_60/bin/java 2
# alternatives --config java
(Select the version you want)
# alternatives --install /usr/bin/jar jar /opt/jdk1.8.0_60/bin/jar 2
# alternatives --install /usr/bin/javac javac /opt/jdk1.8.0_60/bin/javac 2
# alternatives --set jar /opt/jdk1.8.0_60/bin/jar
# alternatives --set javac /opt/jdk1.8.0_60/bin/javac
# java -version (checks to see you install correct version)
# export JAVA_HOME=/opt/jdk1.8.0_60
# export JRE_HOME=/opt/jdk1.8.0_60/jre
# export PATH=$PATH:/opt/jdk1.8.0_60/bin:/opt/jdk1.8.0_60/jre/bin
请注意，前面的教程没有解释如何将环境变量放入中/etc/environment，因此我在该命令之前停了下来。
以下命令来自该其他教程。我从安装Java之后开始：
//Install Tomcat
Login as sudo user, not root.
# sudo groupadd tomcat
# sudo useradd -M -s /bin/nologin -g tomcat -d /opt/tomcat tomcat
# cd ~
# wget http://mirrors.gigenet.com/apache/tomcat/tomcat-8/v8.0.27/bin/apache-tomcat-8.0.27.tar.gz
# sudo mkdir /opt/tomcat
# sudo tar xvf apache-tomcat-8*tar.gz -C /opt/tomcat --strip-components=1
# cd /opt/tomcat
# sudo chgrp -R tomcat conf
# sudo chmod g+rwx conf
# sudo chmod g+r conf/*
# sudo chown -R tomcat work/ temp/ logs/
# sudo vi /etc/systemd/system/tomcat.service
Cut and paste the following file contents:
##################################################
# Systemd unit file for tomcat
[Unit]
Description=Apache Tomcat Web Application Container
After=syslog.target network.target
[Service]
Type=forking
Environment=JAVA_HOME=/usr/lib/jvm/jre
Environment=CATALINA_PID=/opt/tomcat/temp/tomcat.pid
Environment=CATALINA_HOME=/opt/tomcat
Environment=CATALINA_BASE=/opt/tomcat
Environment='CATALINA_OPTS=-Xms512M -Xmx1024M -server -XX:+UseParallelGC'
Environment='JAVA_OPTS=-Djava.awt.headless=true -Djava.security.egd=file:/dev/./urandom'
ExecStart=/opt/tomcat/bin/startup.sh
ExecStop=/bin/kill -15 $MAINPID
User=tomcat
Group=tomcat
[Install]
WantedBy=multi-user.target
##################################################
# sudo systemctl daemon-reload
# sudo systemctl start tomcat
Job for tomcat.service failed. See 'systemctl status tomcat.service' and 'journalctl -xn' for details.
# sudo systemctl start tomcat.service
tomcat.service的作业失败。有关详细信息，请参见“ systemctl状态tomcat.service”和“ journalctl -xn”。＃sudo systemctl启用tomcat.service ln -s'/etc/systemd/system/tomcat.service''/etc/systemd/system/multi-user.target.wants/tomcat.service'＃sudo systemctl启用tomcat
# sudo systemctl status tomcat.service
tomcat.service - Apache Tomcat Web Application Container
Loaded: loaded (/etc/systemd/system/tomcat.service; enabled)
Active: failed (Result: exit-code) since Tue 2015-10-13 11:05:31 PDT; 47s ago
Oct 13 11:05:31 localhost.localdomain kill[20887]: -q, --queue <sig> use sigqueue(2) rather than kill(2)
Oct 13 11:05:31 localhost.localdomain kill[20887]: -p, --pid print pids without signaling them
Oct 13 11:05:31 localhost.localdomain kill[20887]: -l, --list [=<signal>] list signal names, or convert one to a name
Oct 13 11:05:31 localhost.localdomain kill[20887]: -L, --table list signal names and numbers
Oct 13 11:05:31 localhost.localdomain kill[20887]: -h, --help display this help and exit
Oct 13 11:05:31 localhost.localdomain kill[20887]: -V, --version output version information and exit
Oct 13 11:05:31 localhost.localdomain kill[20887]: For more details see kill(1).
Oct 13 11:05:31 localhost.localdomain systemd[1]: tomcat.service: control process exited, code=exited status=1
Oct 13 11:05:31 localhost.localdomain systemd[1]: Failed to start Apache Tomcat Web Application Container.
Oct 13 11:05:31 localhost.localdomain systemd[1]: Unit tomcat.service entered failed state.
yum localinstall如本其他帖子所述，执行更新的jdk rpm的操作无效。
编辑：
按照@Bram的建议，我将配置文件更改为以下内容，但仍收到相同的错误：
# Systemd unit file for tomcat
[Unit]
Description=Apache Tomcat Web Application Container
After=syslog.target network.target
[Service]
Type=forking
Environment=JAVA_HOME=/opt/jdk1.8.0_60
Environment=CATALINA_PID=/opt/tomcat/temp/tomcat.pid
Environment=CATALINA_HOME=/opt/tomcat
Environment=CATALINA_BASE=/opt/tomcat
Environment='CATALINA_OPTS=-Xms512M -Xmx1024M -server -XX:+UseParallelGC'
Environment='JAVA_OPTS=-Djava.awt.headless=true -Djava.security.egd=file:/dev/./urandom'
ExecStart=/opt/tomcat/bin/startup.sh
ExecStop=/bin/kill -15 $MAINPID
User=tomcat
Group=tomcat
[Install]
WantedBy=multi-user.target
另外，根据@JeffSchaller在聊天中的评论，我能够使tomcat从本地启动，如下所示：
[user@localhost tomcat]$ sudo /opt/tomcat/bin/startup.sh
Using CATALINA_BASE: /opt/tomcat
Using CATALINA_HOME: /opt/tomcat
Using CATALINA_TMPDIR: /opt/tomcat/temp
Using JRE_HOME: /
Using CLASSPATH: /opt/tomcat/bin/bootstrap.jar:/opt/tomcat/bin/tomcat-juli.jar
Tomcat started.
[user@localhost tomcat]$
因此，此OP中的问题似乎与systemd配置有关。我该如何解决？
tomcat日志文件中有任何错误？如果我没记错的话，该文件称为catalina.out或类似的名称。
—
Bram
后面的Tomcat日志
—
CodeMed
sudo systemctl start tomcat.service是一堆需要数百行的权限被拒绝的错误。