13.2.3. 检查 PKI 实例状态
systemctl 命令可用于检查进程的状态，显示进程是否正在运行或停止。例如：
systemctl -l status pki-tomcatd@pki-tomcat.service pki-tomcatd@pki-tomcat.service - PKI Tomcat Server pki-tomcat Loaded: loaded (/lib/systemd/system/pki-tomcatd@.service; enabled) Active: inactive (dead) since Fri 2015-11-20 19:04:11 MST; 12s ago Process: 8728 ExecStop=/usr/libexec/tomcat/server stop (code=exited, status=0/SUCCESS) Process: 8465 ExecStart=/usr/libexec/tomcat/server start (code=exited, status=143) Process: 8316 ExecStartPre=/usr/bin/pkidaemon start tomcat %i (code=exited, status=0/SUCCESS) Main PID: 8465 (code=exited, status=143) Nov 20 19:04:10 pki.example.com server[8728]: options used: -Dcatalina.base=/var/lib/pki/pki-tomcat -Dcatalina.home=/usr/share/tomcat -Djava.endorsed.dirs= -Djava.io.tmpdir=/var/lib/pki/pki-tomcat/temp -Djava.util.logging.config.file=/var/lib/pki/pki-tomcat/conf/logging.properties -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager Nov 20 19:04:10 pki.example.com server[8728]: arguments used: stop Nov 20 19:04:11 pki.example.com server[8465]: Nov 20, 2015 7:04:11 PM org.apache.catalina.core.StandardServer await Nov 20 19:04:11 pki.example.com server[8465]: INFO: A valid shutdown command was received via the shutdown port. Stopping the Server instance. Nov 20 19:04:11 pki.example.com server[8465]: PKIListener: org.apache.catalina.core.StandardServer[before_stop] Nov 20 19:04:11 pki.example.com server[8465]: PKIListener: org.apache.catalina.core.StandardServer[stop] Nov 20 19:04:11 pki.example.com server[8465]: PKIListener: org.apache.catalina.core.StandardServer[configure_stop] Nov 20 19:04:11 pki.example.com server[8465]: Nov 20, 2015 7:04:11 PM org.apache.coyote.AbstractProtocol pause Nov 20 19:04:11 pki.example.com server[8465]: INFO: Pausing ProtocolHandler ["http-bio-8080"] Nov 20 19:04:11 pki.example.com systemd[1]: Stopped PKI Tomcat Server pki-tomcat.
如果实例正在运行，其状态检查会返回类似以下示例的信息：
systemctl -l status pki-tomcatd@pki-tomcat.service
pki-tomcatd@pki-tomcat.service - PKI Tomcat Server pki-tomcat
Loaded: loaded (/lib/systemd/system/pki-tomcatd@.service; enabled)
Active: active (running) since Fri 2015-11-20 19:09:09 MST; 3s ago
Process: 8728 ExecStop=/usr/libexec/tomcat/server stop (code=exited, status=0/SUCCESS)
Process: 9154 ExecStartPre=/usr/bin/pkidaemon start tomcat %i (code=exited, status=0/SUCCESS)
Main PID: 9293 (java)
CGroup: /system.slice/system-pki\x2dtomcatd.slice/pki-tomcatd@pki-tomcat.service
������9293 java -DRESTEASY_LIB=/usr/share/java/resteasy-base -Djava.library.path=/usr/lib64/nuxwdog-jni -classpath /usr/share/tomcat/bin/bootstrap.jar:/usr/share/tomcat/bin/tomcat-juli.jar:/usr/share/java/commons-daemon.jar -Dcatalina.base=/var/lib/pki/pki-tomcat -Dcatalina.home=/usr/share/tomcat -Djava.endorsed.dirs= -Djava.io.tmpdir=/var/lib/pki/pki-tomcat/temp -Djava.util.logging.config.file=/var/lib/pki/pki-tomcat/conf/logging.properties -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Djava.security.manager -Djava.security.policy==/var/lib/pki/pki-tomcat/conf/catalina.policy org.apache.catalina.startup.Bootstrap start
Nov 20 19:09:10 pki.example.com server[9293]: Nov 20, 2015 7:09:10 PM org.apache.catalina.core.StandardService startInternal
Nov 20 19:09:10 pki.example.com server[9293]: INFO: Starting service Catalina
Nov 20 19:09:10 pki.example.com server[9293]: Nov 20, 2015 7:09:10 PM org.apache.catalina.core.StandardEngine startInternal
Nov 20 19:09:10 pki.example.com server[9293]: INFO: Starting Servlet Engine: Apache Tomcat/7.0.54
Nov 20 19:09:10 pki.example.com server[9293]: Nov 20, 2015 7:09:10 PM org.apache.catalina.startup.HostConfig deployDescriptor
Nov 20 19:09:10 pki.example.com server[9293]: INFO: Deploying configuration descriptor /etc/pki/pki-tomcat/Catalina/localhost/ROOT.xml
Nov 20 19:09:12 pki.example.com server[9293]: Nov 20, 2015 7:09:12 PM org.apache.catalina.startup.HostConfig deployDescriptor
Nov 20 19:09:12 pki.example.com server[9293]: INFO: Deployment of configuration descriptor /etc/pki/pki-tomcat/Catalina/localhost/ROOT.xml has finished in 2,071 ms
Nov 20 19:09:12 pki.example.com server[9293]: Nov 20, 2015 7:09:12 PM org.apache.catalina.startup.HostConfig deployDescriptor
Nov 20 19:09:12 pki.example.com server[9293]: INFO: Deploying configuration descriptor /etc/pki/pki-tomcat/Catalina/localhost/pki#admin.xml