Is it mandatory or not to stop/start Applcation server ehen Restarting Database Server?

Good afternoon

I need your help please.
There is a Mantenance Windos which needs to Restart de Database Server 192.x.x.97 to set up some configuration

Is it mandatory or not to stop/start Applcation server that runs in 192.x.x.95 ?
Is it mandatory or not to stop/start apache and Tomcat?
I see some processes running on this server?

I appreciate your help in advanced

$ ps -fea|grep -i tomcat
ictprd   16669     1  0 Jan24 ?        02:09:13 /usr/java/jdk1.8.0_45/jre/bin/java -Djava.util.logging.config.file=/ict/product/ict/apache-tomcat-8.0.32/conf/logging.properties -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Doracle.net.tns_admin=/oracle/app/oracle/product/12.1.0/client_1/network/admin -Djava.awt.headless=true -Xms1024m -Xmx1024m -XX:PermSize=128m -XX:MaxPermSize=1024m -Djava.endorsed.dirs=/ict/product/ict/apache-tomcat-8.0.32/endorsed -classpath /ict/product/ict/apache-tomcat-8.0.32/bin/bootstrap.jar:/ict/product/ict/apache-tomcat-8.0.32/bin/tomcat-juli.jar -Dcatalina.base=/ict/product/ict/apache-tomcat-8.0.32 -Dcatalina.home=/ict/product/ict/apache-tomcat-8.0.32 -Djava.io.tmpdir=/ict/product/ict/apache-tomcat-8.0.32/temp org.apache.catalina.startup.Bootstrap start
ictprd   62781 33636  0 13:12 pts/9    00:00:00 grep -i tomcat

ictprd@prdwbmsapp01<PRD> : [/obc/product/obc/DEV/logs]
$ ps -fea|grep -i apache
ictprd   16669     1  0 Jan24 ?        02:09:13 /usr/java/jdk1.8.0_45/jre/bin/java -Djava.util.logging.config.file=/ict/product/ict/apache-tomcat-8.0.32/conf/logging.properties -Djava.util.logging.manager=org.apache.juli.ClassLoaderLogManager -Doracle.net.tns_admin=/oracle/app/oracle/product/12.1.0/client_1/network/admin -Djava.awt.headless=true -Xms1024m -Xmx1024m -XX:PermSize=128m -XX:MaxPermSize=1024m -Djava.endorsed.dirs=/ict/product/ict/apache-tomcat-8.0.32/endorsed -classpath /ict/product/ict/apache-tomcat-8.0.32/bin/bootstrap.jar:/ict/product/ict/apache-tomcat-8.0.32/bin/tomcat-juli.jar -Dcatalina.base=/ict/product/ict/apache-tomcat-8.0.32 -Dcatalina.home=/ict/product/ict/apache-tomcat-8.0.32 -Djava.io.tmpdir=/ict/product/ict/apache-tomcat-8.0.32/temp org.apache.catalina.startup.Bootstrap start
ictprd   19828     1  0 Jan24 ?        02:46:18 java -Dename=PRD -Dpname=ictbootstrapper -Doracle.net.tns_admin=/oracle/app/oracle/product/12.1.0/client_1/network/admin -Demma.coverage.out.file=ictserver.coverage.ec -Xmx800m -Dorg.omg.CORBA.ORBClass=org.jacorb.orb.ORB -Dorg.omg.CORBA.ORBSingletonClass=org.jacorb.orb.ORBSingleton -cp .:/ict/product/ict/PRD/cfg:/ict/product/ict/PRD/lib/activation.jar:/ict/product/ict/PRD/lib/aopalliance.jar:/ict/product/ict/PRD/lib/api.jar:/ict/product/ict/PRD/lib/asm.jar:/ict/product/ict/PRD/lib/bcpkix-jdk15on.jar:/ict/product/ict/PRD/lib/bcprov-jdk15on.jar:/ict/product/ict/PRD/lib/capi_idl.jar:/ict/product/ict/PRD/lib/capi_server.jar:/ict/product/ict/PRD/lib/centralclient.jar:/ict/product/ict/PRD/lib/centralserver.jar:/ict/product/ict/PRD/lib/cglib.jar:/ict/product/ict/PRD/lib/common.jar:/ict/product/ict/PRD/lib/commons-beanutils-core.jar:/ict/product/ict/PRD/lib/commons-cli.jar:/ict/product/ict/PRD/lib/commons-codec.jar:/ict/product/ict/PRD/lib/commons-dbcp.jar:/ict/product/ict/PRD/lib/commons-digester.jar:/ict/product/ict/PRD/lib/commons-httpclient.jar:/ict/product/ict/PRD/lib/commons-io.jar:/ict/product/ict/PRD/lib/commons-lang.jar:/ict/product/ict/PRD/lib/commons-logging.jar:/ict/product/ict/PRD/lib/commons-pool.jar:/ict/product/ict/PRD/lib/com.springsource.javax.jms.jar:/ict/product/ict/PRD/lib/com.springsource.org.apache.commons.codec.jar:/ict/product/ict/PRD/lib/com.sun.el.jar:/ict/product/ict/PRD/lib/crypto.jar:/ict/product/ict/PRD/lib/FastInfoset.jar:/ict/product/ict/PRD/lib/gson.jar:/ict/product/ict/PRD/lib/guava.jar:/ict/product/ict/PRD/lib/help_2057_central.jar:/ict/product/ict/PRD/lib

Yes, in general you must shutdown the application service (tomcat) first, so it can flush data to the DB.
Then shutdown or restart the DB server.

Wouldn't a "service stop routine" be part of the host shutdown sequence?

Yes there are three separated shells scripts one to stop/starrt APP. 2nd shell to start/stop apache and 3rd shell to start/stop web logic

What happens if I deliberately start/stop APplication but not Apache and WebLogic?
There woul be any problem?

Thanks for your support in advanced