What is Foreign Servers?
Foreign JMS servers can be used as a stand-alone component, similar to messaging bridges. These components target application servers or clusters directly instead of an intermediary component like a JMS server.Bridges vs Foreign Server
The JMS messaging bridge does introduce with an extra hop; messages are put into a local destination and then forwarded to the final destination. This is useful when the remote destination is not on highly available JEE container. The bridge will take the messages even when remote destination is not available and then forward them with build-in retry logic when the remote destination becomes available.
If the remote destination is highly available (WebLogic JMS or IBM MQ Series), foreign JMS server is preferable since it directly access the final destination without an extra hop. Mostly preferable for incoming queues on WebLogic 11g and later releases.
Best practices for Foreign Servers
Our best practices were centered around the standard of creating a single JMS Module per cluster (or app server if it wasn't clustered) and then creating both the Foreign server and the weblogic JMS queues/connection factories within the same module.
Also, having good naming conventions for your sub-deployments and JMS Modules
How does Weblogic Foreign Server works with external messaging system?
Configuring Foreign server on JMS Module
Foreign Server feature makes it possible to easily map to remote instances of WebLogic Server in another cluster or domain. so that they appear in the local JNDI tree as a local JMS object. Once the Foreign Provider is configured within Weblogic, for all practical JMS implementations within the code - it can be called as if it was on local JNDI lookup. Weblogic will make the remote calls transparent to your code. This allows you to change your destination via configuration on the Weblogic console or thru WLST.Working in WLST, We need to connect to the Admin Server because this configuration changes can be done in online mode.
################################## # FOREIGN JMS MODULE CONFIGURATION ################################## fsjms_mod_name1=aFSmod fr_server1=ForeignServer1 cnfurl1=file:/path/mq/bindings initialContextFactory1=com.sun.jndi.fscontext.RefFSContextFactory
Create JMS Module for Foreign Servers
With the WebLogic 11g and later releases, Oracle has tried to merge both the internal and foreign JMS under a universal umbrella. However, the target options were kept different. To provide flexibility with the JMS portion, sub-deployments were introduced. Oracle seems to have been extended sub-deployments to Foreign Servers for the sake of consistency, making things quite complicated/messy.
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| WebLogic Foreign Server - IBM MQ |
Create JMS Foreign Server
This we can configure with the help of three arguments -There must be single JMS Module name per cluster, Multiple definitions of your connection factory will skew the JMS load-balancing.
- Connectiony Factory URL
- Foreign Server name
- Initial Context
Foreign Server MBean
JMS Foreign server is parent MBean with Foreign Connection Factory and Foreign Destination as childs.
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| Foreign Server MBean tree |
The foreign JMS provider can be targeted to a WebLogic Server or a WebLogic Cluster.
Create JMS Foreign Destination
Create JMS Foreign Connection Factory
JMS Foreign Server Destination can be configured with the following details
- Destination Name
- Local JNDI
- RemoteJNDI
The destination properties can be given as follows:
############################################### # FOREIGN JMS DESTINATION CONFIGURATION ############################################### destname1=ForeignDestination1 dest_ljndi1=mq/incoming/response dest_rjndi1=MQSRC_TO_WL_JMS1
Similarly Foreign Connection Factory can be defined with the MQ connection factory details
############################################### # FORIEGN JMS CONNECTION FACTORY CONFIGURATION ############################################### fconf_name1=ForeignConnectionFactory1 fconf_ljndi1=MqConnectionFactory fconf_rjndi1=REMOTE_JNDI1
create_ForeignServer.py
from java.io import File
from java.io import FileOutputStream
from java import io
from java.lang import Exception
from java.lang import Throwable
import os.path
import sys
def getJMSModulePath(jms_module_name):
jms_module_path = "/JMSSystemResources/"+jms_module_name+"/JMSResource/"+jms_module_name
return jms_module_path
def createFSJMSModule(jms_module_name,target_name):
cd('/')
module = create(jms_module_name, "JMSSystemResource")
cluster = getMBean("Clusters/"+cluster_target_name)
module.addTarget(cluster)
def createJMSFS(jms_module_name,cnurl,jms_fs_name,ini_fac):
jms_module_path = getJMSModulePath(jms_module_name)
cd(jms_module_path)
cmo.createForeignServer(jms_fs_name)
cd(jms_module_path+'/ForeignServers/'+jms_fs_name)
cmo.setInitialContextFactory(ini_fac)
cmo.setConnectionURL(cnurl)
cmo.setDefaultTargetingEnabled(bool("true"))
cmo.unSet('JNDIPropertiesCredentialEncrypted')
def getFSpath(jms_module_name,jms_fs_name):
jms_module_path = getJMSModulePath(jms_module_name)
jms_fs_path = jms_module_path+'/ForeignServers/'+jms_fs_name
return jms_fs_path
def createFSdest(jms_module_name,jms_fs_name,jms_dest_name,ljndi,rjndi):
cd('/')
jms_fs_path = getFSpath(jms_module_name,jms_fs_name)
cd(jms_fs_path)
print jms_fs_path
cmo.createForeignDestination(jms_dest_name)
jms_fs_path=jms_fs_path+'/ForeignDestinations/'+jms_dest_name
print jms_fs_path
cd(jms_fs_path)
cmo.setLocalJNDIName(ljndi)
cmo.setRemoteJNDIName(rjndi)
def createFSconf(jms_module_name,jms_fs_name,jms_fconf_name,cljndi,crjndi):
jms_fs_path = getFSpath(jms_module_name,jms_fs_name)
cd(jms_fs_path)
cmo.createForeignConnectionFactory(jms_fconf_name)
cd(jms_fs_path+'/ForeignConnectionFactories/'+jms_fconf_name)
cmo.setLocalJNDIName(cljndi)
cmo.setRemoteJNDIName(crjndi)
############## MAIN SCRIPT starts ##########
envproperty=""
if (len(sys.argv) > 1):
envproperty=sys.argv[1]
else:
print "Environment Property file not specified"
sys.exit(2)
propInputStream=FileInputStream(envproperty)
configProps=Properties()
configProps.load(propInputStream)
adminUser=configProps.get("adminUser")
adminPassword=configProps.get("adminPassword")
adminURL=configProps.get("adminURL")
connect(adminUser,adminPassword,adminURL)
edit()
startEdit()
##############################################
#FOREIGN JMS SERVER CONFIGURATION
##############################################
total_dest=configProps.get("total_dest")
total_fconf=configProps.get("total_fconf")
cluster_target_name=configProps.get("clusterName")
trg=configProps.get("ForeignTargetServer")
fs_mod_name=configProps.get("fsjms_mod_name")
createFSJMSModule(fs_mod_name,trg)
n= int(tot_fs)
for i in range(1,n+1):
fr_server=configProps.get("fr_server"+ str(i))
cnfurl=configProps.get("cnfurl"+ str(i))
ini_context=configProps.get("initialContextFactory"+ str(i))
createJMSFS(fs_mod_name,cnfurl,fr_server,ini_context)
d_name=configProps.get("destname"+ str(i))
d_ljndi=configProps.get("dest_ljndi"+ str(i))
d_rjndi=configProps.get("dest_rjndi"+ str(i))
print d_ljndi,' == ', d_rjndi, b
createFSdest(fs_mod_name,fr_server,d_name,d_ljndi,d_rjndi)
fr_server=configProps.get("fr_server"+ str(i))
j_conf=configProps.get("fconf_name"+ str(i))
cn_ljndi=configProps.get("fconf_ljndi"+ str(i))
cn_rjndi=configProps.get("fconf_rjndi"+ str(i))
createFSconf(fs_mod_name,fr_server,j_conf,cn_ljndi,cn_rjndi)
# #### MAIN SCRIPT END ########################################
save()
activate(block="true")
disconnect()
This script is generic you can add as many foreign server as you wish.
You can better use it for receive the message with foreign servers that are having source at remote location.
It could be connect to WebLogic JMS or it can connect to third party messaging servers such as MQ series or ActiveMQ etc.
You can execute the script as follows:
$ java weblogic.WLST Foreign_jms.py ForeignJms.properties
References:
JMS Foreign Server MDB
Oracle doumentation on Foreign Server creation
commands for WLST scripts. These WLST commands can be applicable from WebLogic 9.x to WebLogic 10.3.6 and latest trending WebLogic 12c as well.
