How to swap a server in and Out of cluster during runtime - weblogic

I am implementing session replication in my application. This is old application.
I made all changes and now need to test the server switch and confirm that the objects in session is properly carried to another server in server list.
I have 1 Admin server and 2 managed servers. So the cluster is made of 2 managed server.
while testing I have to always bounce the server and test the flow of my application. This process is very time consuming. So I am looking for any other way to sway a server in and out of cluster
during runtime. I asked on Oracle support website , but they said only way to bounce the server.
How can I write a script for this?
Is there a parameter in weblogic or wlproxy plugin config file that help in this switch.
Your help is appreciated.

using Weblogic scripting tool (WLST) in script mode, you can write a script to automate the shutdown / startup of the managed server that you would like to remove temporarily from the cluster.
you create a file with .py extension which will contain the weblogic commands that you would like to run.
shutdown.py:
connect('username','password','t3://adminIP:port')
shutdown('servername')
disconnect()
startup.py:
connect('username','password','t3://adminIP:port')
start('servername')
disconnect()
to run the script from commandline:
java weblogic.WLST c:\myscripts\shutdown.py
you can put this line in a shell/batch script.
Another way is to write a Java program or an ANT script to invoke the commands using the weblogic.jar file that comes with weblogic.

If you were to change the state of a weblogic managed server from running to admin mode then also you can test the session replication.
You can do this from admin console by selecting the managed server and going to control tab and changing the state of the server to Admin. You can change it back to running from the same place.
Using WLST you can use the commands suspend and resume
http://docs.oracle.com/cd/E11035_01/wls100/server_start/server_life.html
http://docs.oracle.com/cd/E14571_01/web.1111/e13813/quick_ref.htm
suspending and resuming managed servers is quicker than shutting it down and restarting it again.
I have tested this at my end and it works fine, ie when I change the state to admin, my request goes to another managed server and the session is also replicated.
I have used the sample WLS cluster replication example available in wls installation.

Related

weblogic server goes down when any database glitches occurs

Dears,
I am facing a problem with my weblogic 12c Server. I have 3 managed nodes and one admin server. I have configured an Oracle Datasource. Whenever any network glitches or database downtime happens, weblogic server also goes down completely. Is there any configuration which I can make to hold on the server until everything comes back.
Servers are trying to restart automatically.But it is in STARTING state. I have to again start all servers and it is taking time. Your suggestions will help me a lot. Thanks in advance.
If you don't want your servers to restart automatically, the server failure action can probably be tweaked:
{managed_server} -> Configuration -> Overload -> Failure Action
However, probably you should be more interested in exploring if you are missing connection timeout config for your datasource.

How to halt provisioning of one VM until another VM is done?

Using Vagrant+Chef Solo I'm setting up two VMs: #1 is a TeamCity server, #2 is a TeamCity agent. Provisioning is done by first installing the TeamCity server package on VM #1, then the agent VM is booted and requests data from the server which is used to install the agent. That whole thing works fine.
But now I want to alter the server after the agent is done provisioning. I want to modify the server's database directly, to change an attribute that is only available after the agent has spun up. But is there a way for one VM's provisioning to trigger another VM? Once the agent is done I'd like to somehow resume provisioning the server, so I can make the database edit..
Any thoughts, recommendations, or feedback welcomed. I'm new to Vagrant, Chef, and TeamCity, so there's a chance I'm missing a much easier solution.
* Why do I want to edit the DB directly you may be wondering? TeamCity agents must be authorized before they can be used, and I want to do this programmatically. The solution I've found is to directly edit the DB, because authorization functionality is not exposed via the TeamCity REST API (as far as I can tell)
If you can test the agent is installed/answering, you may add a ruby block looping over this test before continuing the recipe execution.
This loop should have a sleep and a counter to avoid infinite loops.
I've no knowledge of teamcity, so can't tell if it's the best way.
In general, Chef is designed to manage your system, not simply provision it (though this is less true in the modern Cloud world with "golden image" strategies). Nonetheless, in your case, you best bet is to just setup chef-client as a service that runs every 15 minutes. Once the client has finished provisioning, the next run of the server will be able to authorize it.
If you really want to "trigger" the one from the other, you'd need either do that externally with something like etcd or consul, or you would need to setup an ssh keypair between the boxes and add a ruby_block on the client that either does the database modification directly, or calls chef-client on the server.

Perforce replica server that can write to main server and has build capability

I need to customize the Perforce server to achieve the following requirements:
I need a local replica server which gets synced with the main server in a different geographical location. I can have the same time zone settings for the local and main servers
The client should be able to commit to the replica server.
The replica server will have build capability as well as a test frame work that is run whenever a build is succesfull.
Once the build and test is succesfull the code should get committed to main server.
I know that the replica server provided by perforce is used as a readonly server which can't write to main server and the forwarding replica just forwards the commands to main server.
I can't use proxy server, as the local server should work even when the main server is offline.
Is it possible to do this? Can anyone point me to some articles which would help me to set up such a server
I had asked the same question in the Perforce forum, but the question is still under verification by moderators.
An edge/commit setup may meet your requirements, as an Edge Server handles some local operations associated with workspaces and work in progress.
As well as read-only commands, the following operations can be performed on an Edge Server:
syncing, checking out, merging, resolving, and reverting files
More information about edge/commit archetecture is available here:
http://www.perforce.com/perforce/doc.current/manuals/p4dist/chapter.distributed.html
You may also want to look at BuildFarm servers:
http://www.perforce.com/perforce/doc.current/manuals/p4dist/chapter.replication.html#DB5-72814
Hope this helps,
Jen!
Build Server doesn't allow build work spaces to submit files. If submitting files is required as part of the build process, consider the use of an edge server to support your automated build processes.
With the implementation of edge servers in 2013.2, we now recommend that you use an edge server instead of a build farm server.
Edge servers offer all the functionality of build farm servers and yet offload more work from the main server and improve performance, with the additional flexibility of being able to run write commands as part of the build process.

Remotely start stop jboss server

I have a requirement to write a java program to remotely start stop a jboss server on request. Can anyone please suggest how could it be done? One option could be invoke start/stop script but this java program(may be servlet or jsp) exists on different machine. We are using jboss server 7.
A simple method to start and stopping Jboss remotely can be done with the run.sh and shutdown.sh script, by pointing to the right host and port. If you are on Linux you can run:
rsh user#host /path/to/jboss/bin/run.sh
rsh user#host /path/to/jboss/bin/shutdown.sh
You can also execute a Shell command with Java, you can use Runtime exec mewthod:
Runtime.getRuntime().exec("shell command here");
See this complete answer for more details on Java exec method.
A better alternative I would suggest, is to use JMX-console programmatically, you can stop/restart a Jboss intance by invoking the shutdown method on the Server MBean. JMX approach is more powerful because you can monitor and manage every aspect of the Jboss runinng instanace (like logging, memory or cpu). See this to start.
I've created a snippet to ease your start, see this working solution http://snipt.org/Ahhjh4
Remember:
create a Jboss user on the Jboss instance using add-user.sh (JBOSS_HOME/bin)
include the jboss-client.jar in your client class-path (the jar is in JBOSS_HOME/bin/client)
Good luck!

Why are my WebLogic clustered MDB app deployments in warning state?

I have a WebLogic cluster on which I've deployed numerous topics and applications that use them. My applications uniformly show themselves in a Warning status. Looking at Monitoring on the deployment, I see the MDB application connects to Server #1, but on server #2 it shows this:
MDB application appName is NOT connected to messaging system.
My JMS Server is targetted to a migratable target, which is in turn targetted to the #1 server and has a cluster identified. And messages sent to either server all flow as expected. I just don't know why these deployments show in a Warning state.
WebLogic 11g
This can be avoided by using the parameter below
<start-mdbs-with-application>false</start-mdbs-with-application>
In the weblogic-application.xml, Setting start-mdbs-with-application to false forces MDBs to defer starting until after the server instance opens its listen port, near the end of the server boot up process.
If you want to perform startup tasks after JMS and JDBC services are available, but before applications and modules have been activated, you can select the Run Before Application Deployments option in the Administration Console (or set the StartupClassMBean’s LoadBeforeAppActivation attribute to “true”).
If you want to perform startup tasks before JMS and JDBC services are available, you can select the Run Before Application Activations option in the Administration Console (or set the StartupClassMBean’s LoadBeforeAppDeployments attribute to “true”).
Refer :http://docs.oracle.com/cd/E13222_01/wls/docs81/ejb/message_beans.html
this is applicable for the versions till 12c and later
I don't like unanswered questions, so I'm going to answer this one.
The problem is resolved, though I was not involved in its resolution. At present the problem only exists for the length of time it takes the JMS subsystem to fully initialize. During that period (with many queues, it can take a while) the JNDI system throws errors and the apps are truly in warning state. Once the JMS is fully initialized, everything goes green.
My belief is that someone corrected something in the JMS Server / Cluster config. I'll never know what it was.