Hai Mark
One more small clarity required on the previous reply with respective
to the below point.
You can use the FarmWarDeployer if you wish but you don't have to.
Generally, the right answer here will be driven by how your organisation
manages files on servers.
>>>> Ok..If Iam having a load-balancer serving 2 tomcat instances configured
>>>> with autoDeploy="true" and unpackWARs="false" in their server.xml
>>>> respectively, running on two separate VMs. Also, Iam having a common share
>>>> such as NFS folder mounted on both servers. This share folder contains a
>>>> single folder named prod_webapps which contains all the required
>>>> application war files that needs to be deployed on both tomcat servers.
Can I have this prod_webapps folder soft-linked to both
tomcat1/webapps folder and tomact2/webapps folder, so that we can have
a centralized webapps deployment folder. Is this possible? Will this
scenario feasible for Production deployment?
Thank You
Vinu VS
On Tue, Jan 29, 2019 at 3:43 PM Mark Thomas <ma...@apache.org> wrote:
>
> On 29/01/2019 06:56, Vinu Vibhu Sobhana wrote:
> > Hai Mark,
> >
> > Please find my comments on the reply sent earlier as some points are
> > still remain unclear.
> >
> >> I have been assigned a new project that requires a web application to
> >> be hosted using Tomcat-Cluster, as it is expected to receive high
> >> traffic.
> > High traffic may be a justification for load-balancing. It is not a
> > justification for session replication.
> >
> >>>> Since we would be receiving high traffic it was decided to go with
> >>>> multiple instances of tomcat using a load-balancer.
> >
> > Why 2 instances per VM rather than one larger instance per VM?
> >>>> So for this point it is understood that it is best that we put only one
> >>>> instance per VM (with large hardware resource). Iam I correct. Will the
> >>>> same scenario be applicable while using physical machine. ie one Tomcat
> >>>> instance per machine. What about the resource limitation (ie. any memory
> >>>> allocation pool for a JVM, etc.) required that must be noted.
>
> The right configuration will depend on the app. Generally, for a well
> written app one JVM per VM will be the best choice but only testing will
> tell for sure.
>
> >> Point 1
> > Don't use any clustering at all.
> >
> >>>> This point was not clear at all. Are you suggesting that we configure
> >>>> Tomcat instances without cluster and configure the load balancer with
> >>>> session management and stickiness features to manage sessions??
>
> Yes. Don;t use clustering unless you really need it.
>
> >> Point 2
> > N/A since clustering is not required.
> >
> >>>> If clustering is required for other scenarios, then please comment on
> >>>> this point how should we deploy applications using Tomcat Manager App on
> >>>> FarmWarDeployer folder
>
> You can use the FarmWarDeployer if you wish but you don't have to.
> Generally, the right answer here will be driven by how your organisation
> manages files on servers.
>
> >> Point 3
> > No.
> >>>> This means that there is mo method to collect the errors for individual
> >>>> domain when VirtualHost element is enabled. If there is any work-around
> >>>> please suggest. Also will the catalina.out log contains errors for these
> >>>> VirtualHost element?
>
> There is no workaround.
>
> A well written application should not be writing anything to catalina.out
>
> >> Point 8
> > Configure the load-balancer to use sticky sessions. You'll need to do
> > that anyway if clustering is removed.
> >
> >>>> With respect to my project specification mentioned in point 8, you have
> >>>> suggested to go with a load-balancer serving 2 tomcat instances, each
> >>>> running on two separate VMs with enough resources. Moreover, these
> >>>> tomcat instances are NOT to be in Clustered State and the session must
> >>>> be managed by an external Load-balancer using Stick bit mode enable. Is
> >>>> it correct?.
>
> Yes.
>
> > Is Tomcat CPU intrinsic or Memory?
>
> I don't understand the question.
>
> Mark
>
> > --
> > Thank You
> > Vinu VS
> >
> >
> > On Mon, Jan 28, 2019 at 3:00 PM Mark Thomas <ma...@apache.org> wrote:
> >>
> >> On 28/01/2019 07:25, Vinu Vibhu Sobhana wrote:
> >>> Hai
> >>>
> >>> First of all Iam new to Tomcat-Cluster and hence I apologize if my
> >>> doubts are wrong.
> >>>
> >>> I have been assigned a new project that requires a web application to
> >>> be hosted using Tomcat-Cluster, as it is expected to receive high
> >>> traffic.
> >>
> >> High traffic may be a justification for load-balancing. It is not a
> >> justification for session replication.
> >>
> >>> So, I have configured a Tomcat-Cluster with 4 Tomcat
> >>> instances (ie 2 - Tomcat instances running on 2 VMs each), where they
> >>> shall receive hits its through a load-balancer. As I new to
> >>> Tomcat-Cluster, I have to clear some points before approving the
> >>> project to go on-line.
> >>
> >> Why 2 instances per VM rather than one larger instance per VM?
> >>
> >>>
> >>> My queries are :
> >>>
> >>> 1. The Clustering of Tomcat currently configured is using the Delta
> >>> Manger for managing session replications. Is it the correct choice or
> >>> should I go for Backup Manger or any third party session management
> >>> software such as memcache or redis.
> >>
> >> Don't use any clustering at all.
> >>
> >>> 2. While using Tomcat-Cluster, can we use/configure the Tomcat Manager
> >>> App to deploy applications on FarmWarDeployer folder or is there any
> >>> other method to do so.
> >>
> >> N/A since clustering is not required.
> >>
> >>> 3. Virtual Host entry has been implemented for our project domain
> >>> "webportal.xyz.in" where only the access logs are getting logged to
> >>> "webportal.xyz.in_access_log". Is there any means by which I can
> >>> receive the error-logs also for this domain on a separate file.
> >>
> >> No.
> >>
> >>> 4. Is there any method to tune/tweak my current server.xml file so
> >>> that clustering method can be done globally rather than applying
> >>> individually on every Host entry with different ports.
> >>
> >> No. Each instance needs to be configured individually. You can use
> >> templating. With careful configuration you can have a commons server.xml
> >> with ${...} property replacement for all the instance specific settings
> >> that are then configured in catalina.properties
> >>
> >>> 5. How to enable SSL for Tomcat-Cluster. Should I need to install SSL
> >>> Certificates on all 4 tomcat instances or only on the Load-balancer.
> >>
> >> Either works. The right solution depends on your security requirements.
> >> Note: If you terminate TLS at the load-balancer you need to be very
> >> careful to make sure that the Tomcat instances are able to determine
> >> which requests were received over TLS and which were not else you are
> >> likely to have a bunch of security holes - mainly around cookie/session
> >> handling.
> >>
> >>> 6. What all parameters needs to be checked/considered for tuning the
> >>> Tomcat / Tomcat-Cluster instance while hosting any Project on
> >>> Production environment.
> >>
> >> All of them. Each application is unique. There is no "makeItFaster"
> >> attribute.
> >>
> >>> 7. Is there any service reload option present for tomcat, ie. similar
> >>> to the one present in apache where the sessions doesn't get
> >>> invalidated while tuning/updating the server config files.
> >>
> >> Yes. It is enabled by default.
> >> http://tomcat.apache.org/tomcat-9.0-doc/config/manager.html#Persistence_Across_Restarts
> >>
> >>> 8. One of the issue noted was that one of the security feature
> >>> implemented for this projects stopped working while moving to
> >>> Tomcat-Cluster environment.
> >>>
> >>> Our application uses java spring mvc
> >>> "<spring.version>4.3.5.RELEASE</spring.version>,
> >>> <spring.security.version>4.2.0.RELEASE</spring.security.version>"
> >>> where it is configured to allow only one time login for all users
> >>> until their current login session expires or have been invalidated.
> >>> ie. if multiple logins are done, only the last login will be active
> >>> all the rest gets automatically logged-out. it was implemented for
> >>> some customer security reasons. This was working fine while running on
> >>> a single Tomcat instance. But while deploying on a Clustered instance
> >>> it is not working unless if the same user logs into the same tomcat
> >>> instance of the cluster. Is there any solution to this problem or
> >>> should the developers needs to reconfigure the application to meets
> >>> Tomcat-Clusters concepts.
> >>
> >> Configure the load-balancer to use sticky sessions. You'll need to do
> >> that anyway if clustering is removed.
> >>
> >> Mark
> >>
> >>
> >>>
> >>> Please find the server.xml and context.xml for one of my Tomcat
> >>> instances present in Cluster mentioned below.
> >>>
> >>> server.xml
> >>> #############
> >>> <?xml version="1.0" encoding="UTF-8"?>
> >>> <Server port="8105" shutdown="SHUTDOWN">
> >>> <Listener
> >>> className="org.apache.catalina.startup.VersionLoggerListener" />
> >>> <!-- <Listener
> >>> className="org.apache.catalina.core.AprLifecycleListener"
> >>> SSLEngine="on" /> -->
> >>> <Listener
> >>> className="org.apache.catalina.core.JreMemoryLeakPreventionListener"
> >>> />
> >>> <Listener
> >>> className="org.apache.catalina.mbeans.GlobalResourcesLifecycleListener"
> >>> />
> >>> <Listener
> >>> className="org.apache.catalina.core.ThreadLocalLeakPreventionListener"
> >>> />
> >>> <GlobalNamingResources>
> >>> <Resource name="UserDatabase" auth="Container"
> >>> type="org.apache.catalina.UserDatabase" description="User database
> >>> that can be updated and saved"
> >>> factory="org.apache.catalina.users.MemoryUserDatabaseFactory"
> >>> pathname="conf/tomcat-users.xml" />
> >>> </GlobalNamingResources>
> >>> <Service name="Catalina">
> >>> <Connector port="8080" protocol="HTTP/1.1"
> >>> connectionTimeout="20000" />
> >>> <Connector port="8109" protocol="AJP/1.3" />
> >>> <Engine name="Catalina" defaultHost="localhost" jvmRoute="jvm1">
> >>> <Realm className="org.apache.catalina.realm.LockOutRealm">
> >>> <Realm
> >>> className="org.apache.catalina.realm.UserDatabaseRealm"
> >>> resourceName="UserDatabase" />
> >>> </Realm>
> >>> <Host name="localhost" appBase="webapps" unpackWARs="true"
> >>> autoDeploy="true">
> >>> <!--##################################################
> >>> LOCALHOST TOMCAT CLUSTERED BEGIN
> >>> ########################################### -->
> >>> <Cluster
> >>> className="org.apache.catalina.ha.tcp.SimpleTcpCluster"
> >>> channelSendOptions="4" channelStartOptions="3">
> >>> <Channel
> >>> className="org.apache.catalina.tribes.group.GroupChannel">
> >>> <Receiver
> >>> className="org.apache.catalina.tribes.transport.nio.NioReceiver"
> >>> address="web1.xyz.in" port="4000" autoBind="9" selectorTimeout="5000"
> >>> maxThreads="6" />
> >>> <Sender
> >>> className="org.apache.catalina.tribes.transport.ReplicationTransmitter">
> >>> <Transport
> >>> className="org.apache.catalina.tribes.transport.nio.PooledParallelSender"
> >>> />
> >>> </Sender>
> >>> <Interceptor
> >>> className="org.apache.catalina.tribes.group.interceptors.TcpPingInterceptor"
> >>> />
> >>> <Interceptor
> >>> className="org.apache.catalina.tribes.group.interceptors.TcpFailureDetector"
> >>> />
> >>> <Interceptor
> >>> className="org.apache.catalina.tribes.group.interceptors.MessageDispatchInterceptor"
> >>> />
> >>> <Interceptor
> >>> className="org.apache.catalina.tribes.group.interceptors.StaticMembershipInterceptor">
> >>> <Member
> >>> className="org.apache.catalina.tribes.membership.StaticMember"
> >>> port="4001" securePort="-1" host="web1.xyz.in" domain="local-cluster"
> >>> uniqueId="{2,3,4,5,6,7,8,9,10,11,12,13,14,15,0,1}" />
> >>> <Member
> >>> className="org.apache.catalina.tribes.membership.StaticMember"
> >>> port="4000" securePort="-1" host="web2.xyz.in" domain="local-cluster"
> >>> uniqueId="{2,3,4,5,6,7,8,9,10,11,12,13,14,15,0,1}" />
> >>> <Member
> >>> className="org.apache.catalina.tribes.membership.StaticMember"
> >>> port="4001" securePort="-1" host="web2.xyz.in" domain="local-cluster"
> >>> uniqueId="{2,3,4,5,6,7,8,9,10,11,12,13,14,15,0,1}" />
> >>> </Interceptor>
> >>> </Channel>
> >>> <Valve
> >>> className="org.apache.catalina.ha.tcp.ReplicationValve" filter="" />
> >>> <Valve
> >>> className="org.apache.catalina.ha.session.JvmRouteBinderValve" />
> >>> <ClusterListener
> >>> className="org.apache.catalina.ha.session.ClusterSessionListener" />
> >>> <Deployer
> >>> className="org.apache.catalina.ha.deploy.FarmWarDeployer"
> >>> tempDir="/usr/local/tomcat-cluster/tomcat1/temp/"
> >>> deployDir="/usr/local/tomcat-cluster/tomcat1/webapps/"
> >>> watchDir="/usr/local/tomcat-cluster/tomcat1/watchdir/"
> >>> watchEnabled="true" />
> >>> </Cluster>
> >>> <!--##################################################
> >>> LOCALHOST TOMCAT CLUSTERED END
> >>> ########################################### -->
> >>> <Valve
> >>> className="org.apache.catalina.valves.AccessLogValve" directory="logs"
> >>> prefix="localhost_access_log" suffix=".txt" pattern="%h %l %u %t
> >>> &quot;%r&quot; %s %b" />
> >>> </Host>
> >>>
> >>> <Host name="webportal.xyz.in" appBase="webportal_webapps"
> >>> unpackWARs="true" autoDeploy="true">
> >>> <Alias>www.webportal.xyz.in</Alias>
> >>> <!--##################################################
> >>> webportal.xyz.in TOMCAT CLUSTERED BEGIN
> >>> ########################################### -->
> >>> <Cluster
> >>> className="org.apache.catalina.ha.tcp.SimpleTcpCluster"
> >>> channelSendOptions="4" channelStartOptions="3">
> >>> <Channel
> >>> className="org.apache.catalina.tribes.group.GroupChannel">
> >>> <Receiver
> >>> className="org.apache.catalina.tribes.transport.nio.NioReceiver"
> >>> address="web1.xyz.in" port="5000" autoBind="9" selectorTimeout="5000"
> >>> maxThreads="6" />
> >>> <Sender
> >>> className="org.apache.catalina.tribes.transport.ReplicationTransmitter">
> >>> <Transport
> >>> className="org.apache.catalina.tribes.transport.nio.PooledParallelSender"
> >>> />
> >>> </Sender>
> >>> <Interceptor
> >>> className="org.apache.catalina.tribes.group.interceptors.TcpPingInterceptor"
> >>> />
> >>> <Interceptor
> >>> className="org.apache.catalina.tribes.group.interceptors.TcpFailureDetector"
> >>> />
> >>> <Interceptor
> >>> className="org.apache.catalina.tribes.group.interceptors.MessageDispatchInterceptor"
> >>> />
> >>> <Interceptor
> >>> className="org.apache.catalina.tribes.group.interceptors.StaticMembershipInterceptor">
> >>> <Member
> >>> className="org.apache.catalina.tribes.membership.StaticMember"
> >>> port="5001" securePort="-1" host="web1.xyz.in" domain="web-cluster"
> >>> uniqueId="{2,3,4,5,6,7,8,9,10,11,12,13,14,15,0,1}" />
> >>> <Member
> >>> className="org.apache.catalina.tribes.membership.StaticMember"
> >>> port="5000" securePort="-1" host="web2.xyz.in" domain="web-cluster"
> >>> uniqueId="{2,3,4,5,6,7,8,9,10,11,12,13,14,15,0,1}" />
> >>> <Member
> >>> className="org.apache.catalina.tribes.membership.StaticMember"
> >>> port="5001" securePort="-1" host="web2.xyz.in" domain="web-cluster"
> >>> uniqueId="{2,3,4,5,6,7,8,9,10,11,12,13,14,15,0,1}" />
> >>> </Interceptor>
> >>> </Channel>
> >>> <Valve
> >>> className="org.apache.catalina.ha.tcp.ReplicationValve" filter="" />
> >>> <Valve
> >>> className="org.apache.catalina.ha.session.JvmRouteBinderValve" />
> >>> <ClusterListener
> >>> className="org.apache.catalina.ha.session.ClusterSessionListener" />
> >>> <Deployer
> >>> className="org.apache.catalina.ha.deploy.FarmWarDeployer"
> >>> tempDir="/usr/local/tomcat-cluster/tomcat1/temp/"
> >>> deployDir="/usr/local/tomcat-cluster/tomcat1/webportal_webapps/"
> >>> watchDir="/usr/local/tomcat-cluster/tomcat1/webportal_webapps_watchdir/"
> >>> watchEnabled="true" />
> >>> </Cluster>
> >>> <!--##################################################
> >>> webportal.xyz.in TOMCAT CLUSTERED END
> >>> ########################################### -->
> >>> <Valve
> >>> className="org.apache.catalina.valves.AccessLogValve" directory="logs"
> >>> prefix="webportal.xyz.in_access_log" suffix=".txt" pattern="%h %l %u
> >>> %t &quot;%r&quot; %s %b" />
> >>> </Host>
> >>> </Engine>
> >>> </Service>
> >>> </Server>
> >>> #############
> >>>
> >>> context.xml
> >>> #############
> >>> <?xml version="1.0" encoding="UTF-8"?>
> >>> <Context>
> >>> <WatchedResource>WEB-INF/web.xml</WatchedResource>
> >>> <WatchedResource>${catalina.base}/conf/web.xml</WatchedResource>
> >>> <Manager className="org.apache.catalina.ha.session.DeltaManager"
> >>> expireSessionsOnShutdown="false"
> >>> notifyListenersOnReplication="true"/>
> >>> </Context>
> >>> #############
> >>>
> >>
> >>
> >> ---------------------------------------------------------------------
> >> To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
> >> For additional commands, e-mail: users-h...@tomcat.apache.org
> >>
> >
> >
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
> For additional commands, e-mail: users-h...@tomcat.apache.org
>
--
Thank You
Best regards
Vinu Vibhu Sobhana
Disclaimer: This e-mail and any files transmitted with it are intended
for the named addresses only and may contain privileged and
confidential information. If you have received this e-mail in error,
please notify the sender by e-mail reply immediately and delete it
from your system. You may not copy this message and its attachments or
disclose its contents to any other person, use it for any purpose or
store it by any means. Any form of reproduction, dissemination,
copying, disclosure, modification, distribution and / or publication
of this message without the prior written consent of the author of
this e-mail is strictly prohibited. Although this e-mail and its
attachments are believed to be free from virus, it is the
responsibility of the recipient to ensure that they are virus free.
---------------------------------------------------------------------
To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org
For additional commands, e-mail: users-h...@tomcat.apache.org
