CORBA Failover

I have a java system that is connecting to a C++ server using a corba connection. I am using an IOR string generated by the C++ server to resolve the host/port and whatnot. I am trying to find a way to have this connection failover to a secondary identical C++ server if the first goes down for some reason. The actual failover doesnt seem like the difficult part. Seems like catching the exception thrown becuase of the connection failure is more tricky. Has anyone done something similar before? Not sure which exception I need to catch and where. Any help would be appreciated.
Thanks for the help,
Scott

Similar Messages

Hot to do Failover/Load balance on CORBA C++ Client

I have a corba C++ client using Bea/Tuxedo 8.0 ORB talking to stateless session beans
on Weblogic Server 6.1/sp2.
Question:
If the wls server(s) is a cluster, how do I use this feature in my C++ client to
provide the failover/load balance?
Will the rmic generate idl which is cluster-aware if the EJBs are clustered?
Any help is appreciated.
Thanks,
steve

"steve" <[email protected]> writes:
I have a corba C++ client using Bea/Tuxedo 8.0 ORB talking to stateless session beans
on Weblogic Server 6.1/sp2.
Question:
If the wls server(s) is a cluster, how do I use this feature in my C++ client to
provide the failover/load balance?Currently, although the information is available to the client it does
not use it. This will probably change in a future release of Tuxedo,
but you should talk to your sales rep for details.
For now you can get some degree of failover by catching the
COMM_FAILURE exception and re-looking up CosNaming and your bean.
Will the rmic generate idl which is cluster-aware if the EJBs are clustered?The information is provided dynamically at runtime, so its independent
of the IDL.
andy

Event Loop in SO and failover

Hi, All Forte Experts
I have 2 questions:
1. Would any one tell me where can I put the event loop block in a
Service Object?
I tried to put it in the Init to get a timer.tick event, but the SO
hanged to wait there.
How can I do this to let the SO do something at certain time?
2. I have SO doing failover. Can one sleeping SO get any kind of
information when it becomes alive
after the running SO dies?
Thanks a lot for your help.
Alex
Carpe Diem, Seize the Day !
Alex Lee (Li Zhongling)
Forte, Java/CORBA Group
International Business Corporation
Bangalore 560010, India
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'unsubscribe forte-users' as the body of the message.
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Hi,
Thank you all a lot for your help.
For the second question, I explain the situation here. I have a failover
LockManager SO which contains a LockList. When the first running SO dies, I
want the second one to become alive and restore the state of the first one( I
mean the LockList should not be lost). Then I tried to do it in this way:
1. As Daniel Nguyen suggested in Re:Retaining state on failover of SO
(Jan.19,1999), I put one shared object holding one Locklist on the Router
partition. Let the running SO always refresh its contents.
2. I make the SO Transactionaln with Transaction Dialog Duration. On the
client, every time I start a transaction to add or remove lock through SO, I
try to catch the exception "AbortException" (which means the SO dies). To
handle the exception, I use Releaseconnection, then force the backup SO get the
locklist from the shared object on Router partition. In this way, the backup SO
becomes alive and also restore the state.
I think this works. I will also try your suggestion ASAP. However, would you
please tell me how to control the secondary SO not to start and later to start
it? Every time I try to run the app, all the partition will start. And I guess,
I can not new it.
Thanks.
Rds
Alex
Alex,
1) as Arpad mentioned in his posting, you can start task a method which
contains your event loop from the init method.
as for
2), what I've done in the past is to start both primary and secondary SOs,
where the primary SO's event loop begins at start up, but the secondary SO
is dormant.. I created a "monitoring" SO which listens for remote access
exceptions (or distributed access exceptions) and on the death of the first
SO, the second SO's event loop is started. The other option is to not start
the secondary SO until the primary one fails, but there is a lag time for
the SO to come up.
j
Carpe Diem, Seize the Day !
Alex Lee (Li Zhongling)
Forte, Java/CORBA Group
International Business Corporation
Bangalore 560010, India
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'unsubscribe forte-users' as the body of the message.
Searchable thread archive <URL:http://pinehurst.sageit.com/listarchive/>

Failover is work, but Session replication doesn't work!

Dear all,
          My Cluster can failover, but can't session replicate....
          I start up the 2 WLS 6.0 and the Web Server, then I visit
          http://web_server_ip/myWebApp/SessionServlet serveral times, then the
          counter variable in the session raise up, then I down the "target" WLS, then
          I try http://web_server_ip/myWebApp/SessionServlet now, I can call but the
          counter restart.... so the session seems not yet replicated. what I can
          do...?!
          My Setup: I setup a Netscape Web Server 3.6.3 as the proxy using libproxy.so
          with the cluster setting, and use 2 WLS 6.0 (both are running in 7001,7002)
          as the Application Server Cluster (WLCluster). one WLS is on Unix Machine
          and the other in on a NT. I set the 2 WLSs: the Primary Group is
          "WL_rep_group1", and set the secondary is "WL_rep_group2".
          Deployment: I deploy the application "myWebApp" (.war) on the servers unix
          and nt, adn also deploy to the cluster WLCluster.
          I deploy the examplesWebApp to my created domain "demo", and modify the
          weblogic.xml:
          <weblogic-web-app>
          <session-descriptor>
          <session-param>
          <param-name>PersistentStoreType</param-name>
          <param-value>replicated</param-value>
          </session-param>
          </session-descriptor>
          <jsp-descriptor>
          <jsp-param>
          <param-name>
          pageCheckSeconds
          </param-name>
          <param-value>
          1
          </param-value>
          </jsp-param>
          <jsp-param>
          <param-name>
          verbose
          </param-name>
          <param-value>
          true
          </param-value>
          </jsp-param>
          </jsp-descriptor>
          </weblogic-web-app>
          so ... anything I did wrong, so the WLS can't do Session replication??!!
          Please Help or Comment!
          Thanks in advance!
          with thanks,
          Alex Wong


Dear Vinod and Kevin,
          Some more information that I think it may help.
          First, I want to correct 1 point in my previous message, the Replication
          Group is "WLRepGroup1" and the Preferred Secondary Group is "WLRepGroup2"
          for the 2 machine WLSs.
          Second, I found that the Multicast Communication is not functioning becoz
          the switch of my office block the 224.0.0.1's communication, so now I added
          a hub for this 2 machine, as a result the multicast is wokring... at least
          pass the java utils.MulticastTest....
          Thrid, after the mutlicast work, I try the SessionServlet, it is working at
          beginning... but after some more clicks, one server will cause the following
          error (this time crash on x.y.z.b--NT machine)....
          -------- (a long list, the IPs are replaced: x.y.z.a UNIX machine, x.y.z.b
          NT machine, x.y.z.c My PC)
          Screen caption on demo>Servers>wlserver2 (monitoring> cluster)
          Unexpected Error
          Connected to x.y.z.a:7001 Active Domain: demo Jun 11, 2001 5:06:23 PM
          GMT+08:00
          An unexpected error was encountered in processing your request.
          Exception
          java.lang.NullPointerException
          <>
          Current Date
          Mon Jun 11 17:06:23 GMT+08:00 2001
          Console Release Build
          6.0 Service Pack 2
          Console Build
          6.0 Service Pack 2 05/24/2001 11:55:28 #117037
          Server Release Build
          6.0 Service Pack 2
          Server Build
          6.0 Service Pack 2 05/24/2001 11:55:28 #117037
          All Server Product Versions
          WebLogic Server Build: 6.0 Service Pack 2 05/24/2001 11:55:28 #117037
          WebLogic XML Module: 6.0 Service Pack 2 05/24/2001 12:34:27 #117037
          Request Info
          Protocol: HTTP/1.1
          ServerName: x.y.z.a
          ServerPort: 7001
          Secure: false
          ContextPath: /console
          ServletPath: /panels/mbean/Server.jsp
          QueryString:
          mbean=demo%3AName%3Dwlserver2%2CType%3DServer
          PathInfo: null
          PathTranslated: null
          RequestURI: /console/panels/mbean/Server.jsp
          AuthType: null
          ContentType: null
          CharacterEncoding: null
          Locale: zh_TW
          Method: GET
          Session:
          weblogic.servlet.internal.session.MemorySessionData@661950
          RequestedSessionId:
          OyQxOz4LG0WnLjufYcZDkIGGXIVAhHNASdBLUs2seZnvoQ4RXekX/console
          RequestedSessionIdFromCookie: true
          RequestedSessionIdFromURL: false
          UserPrincipal: system
          RemoteUser: system
          RemoteAddr: x.y.z.c
          RemoteHost: x.y.z.c
          Parameters
          mbean = demo:Name=wlserver2,Type=Server
          Attributes
          console.original./console/panels/mbean/Server.jsp.ContextPath = /console
          console.original./console/panels/mbean/Server.jsp.Method = GET
          console.original./console/panels/mbean/Server.jsp.QueryString =
          mbean=demo%3AName%3Dwlserver2%2CType%3DServer
          console.original./console/panels/mbean/Server.jsp.RemoteUser = system
          console.original./console/panels/mbean/Server.jsp.RequestURI =
          /console/panels/mbean/Server.jsp
          console.original./console/panels/mbean/Server.jsp.ServletPath =
          /panels/mbean/Server.jsp
          console.preferences.ContextKey =
          /panels/mbean/Server.jsp
          javax.servlet.include.context_path = /console
          javax.servlet.include.request_uri =
          /console/common/requestinfo.jsp
          javax.servlet.include.servlet_path =
          /common/requestinfo.jsp
          javax.servlet.jsp.jspException =
          java.lang.NullPointerException
          weblogic.httpd.user = system
          weblogic.management.console.tags.ContentTag =
          java.lang.Object@545f89
          weblogic.management.console.tags.HeaderTag =
          java.lang.Object@4c5c6c
          weblogic.management.console.tags.TabbedDialogTag =
          java.lang.Object@7eafc
          Headers
          Accept = image/gif, image/x-xbitmap, image/jpeg, image/pjpeg, */*
          Accept-Encoding = gzip, deflate
          Accept-Language = zh-tw
          Connection = Keep-Alive
          Cookie =
          JSESSIONID=OyQxOz4LG0WnLjufYcZDkIGGXIVAhHNASdBLUs2seZnvoQ4RXekX!143710744761
          7668081!-896735123!7001!7002!NONE
          Host = x.y.z.a:7001
          User-Agent = Mozilla/4.0 (compatible; MSIE 5.01; Windows 98)
          BrowserInfo
          User-Agent: Mozilla/4.0 (compatible; MSIE 5.01; Windows 98)
          IE: true
          Netscape: false
          Supported: true
          JavscriptHrefs: false
          TableCellClick: true
          DocumentReloadedOnResize: false
          DropdownStretchable: true
          CellSpacingBlank: false
          EmptyCellBlank: false
          ImgOnclickSupported: true
          TableBorderFancy: true
          PartialToWideTables: false
          Server System Properties
          bea.home = /u0/weblogic
          file.encoding = ISO8859-1
          file.encoding.pkg = sun.io
          file.separator = /
          java.awt.fonts =
          java.awt.graphicsenv = sun.awt.X11GraphicsEnvironment
          java.awt.printerjob = sun.awt.motif.PSPrinterJob
          java.class.path =
          /u0/weblogic/wlserver6.0:/u0/weblogic/wlserver6.0/lib/weblogic_sp.jar:/u0/we
          blogic/wlserver6.0/lib/weblogic.jar:/opt/oracle/product/8.1.6/jdbc/lib/class
          es12.zip
          java.class.version = 47.0
          java.ext.dirs = /u0/weblogic/jdk130/jre/lib/ext
          java.home = /u0/weblogic/jdk130/jre
          java.io.tmpdir = /var/tmp/
          java.library.path =
          /u0/weblogic/jdk130/jre/bin/../lib/sparc/hotspot:/u0/weblogic/jdk130/jre/bin
          /../lib/sparc::/lib:/usr/local/easysoft/oob/client:/usr/local/easysoft/lib:/
          u0/weblogic/wlserver6.0/lib/solaris:/u0/weblogic/wlserver6.0/lib/solaris/oci
          816_8:/usr/lib
          java.naming.factory.initial =
          weblogic.jndi.WLInitialContextFactory
          java.naming.factory.url.pkgs = weblogic.jndi.factories
          java.protocol.handler.pkgs =
          weblogic.utils|weblogic.utils|weblogic.net|weblogic.management|weblogic.net|
          weblogic.net|weblogic.utils
          java.runtime.name = Java(TM) 2 Runtime Environment,
          Standard Edition
          java.runtime.version = 1.3.0
          java.security.policy =
          =/u0/weblogic/wlserver6.0/lib/weblogic.policy
          java.specification.name = Java Platform API Specification
          java.specification.vendor = Sun Microsystems Inc.
          java.specification.version = 1.3
          java.vendor = Sun Microsystems Inc.
          java.vendor.url = http://java.sun.com/
          java.vendor.url.bug =
          http://java.sun.com/cgi-bin/bugreport.cgi
          java.version = 1.3.0
          java.vm.info = mixed mode
          java.vm.name = Java HotSpot(TM) Client VM
          java.vm.specification.name = Java Virtual Machine
          Specification
          java.vm.specification.vendor = Sun Microsystems Inc.
          java.vm.specification.version = 1.0
          java.vm.vendor = Sun Microsystems Inc.
          java.vm.version = 1.3.0
          javax.rmi.CORBA.PortableRemoteObjectClass =
          weblogic.iiop.PortableRemoteObjectDelegateImpl
          javax.rmi.CORBA.UtilClass = weblogic.iiop.UtilDelegateImpl
          javax.xml.parsers.DocumentBuilderFactory =
          weblogic.xml.jaxp.RegistryDocumentBuilderFactory
          javax.xml.parsers.SAXParserFactory =
          weblogic.xml.jaxp.RegistrySAXParserFactory
          jmx.implementation.name = JMX RI
          jmx.implementation.vendor = Sun Microsystems
          jmx.implementation.version = 1.0
          jmx.specification.name = Java Management Extensions
          jmx.specification.vendor = Sun Microsystems
          jmx.specification.version = 1.0 Final Release
          line.separator =
          os.arch = sparc
          os.name = SunOS
          os.version = 5.6
          path.separator = :
          sun.boot.class.path =
          /u0/weblogic/jdk130/jre/lib/rt.jar:/u0/weblogic/jdk130/jre/lib/i18n.jar:/u0/
          weblogic/jdk130/jre/lib/sunrsasign.jar:/u0/weblogic/jdk130/jre/classes
          sun.boot.library.path =
          /u0/weblogic/jdk130/jre/lib/sparc
          sun.cpu.endian = big
          sun.cpu.isalist = sparcv8plus+vis sparcv8plus
          sparcv8 sparcv8-fsmuld sparcv7 sparc
          sun.io.unicode.encoding = UnicodeBig
          user.dir = /u0/weblogic/wlserver6.0
          user.home = /
          user.language = en
          user.name = root
          user.region = US
          user.timezone = Asia/Hong_Kong
          weblogic.Domain = demo
          weblogic.Name = wlserver1
          weblogic.security.jaas.Configuration =
          weblogic.security.internal.ServerConfig
          weblogic.security.jaas.Policy =
          /u0/weblogic/wlserver6.0/lib/Server.policy
          ---------- End of the message -----------
          any comment?? is that I deploy on wlserver1, wlserver2, WLCluster cause
          error??!! anything I did wrong??!
          please help!! or Comment
          with thanks,
          Alex Wong
          "Alex Wong" <[email protected]> ¼¶¼g©ó¶l¥ó
          news:[email protected]...
          > Hi Vinod and Kevin,
          >
          > Thanks Vinod first, and after I try the session.getClass(), I get the
          > following output
          > class weblogic.servlet.internal.session.ReplicatedSessionData
          > I think that's means I am using "replicated" already, rite?!
          >
          > About the License, I cat the license.bea, there is a license to the
          > "In-memory Replication - Servlet" and "In-memory Replication - EJB",
          however
          > it is a eval license but seems not yet expired, so I don't think that is
          the
          > problem, rite?
          >
          > And a quick question, you tell me "your configuration looks ok" means the
          > H/W configuration, or the WLS configuration??!!
          > Maybe I tell you more about my WLS configuration, so that, you can
          > determinate where I go wrong. (thanks)
          >
          >
          > Vinod and Kevin
          > (Kevin, I am Alex Wong from ASL, if you have any comment, you can simply
          > reply my personal email, thx)
          >
          > Steps I did to create the domain, WLS and Cluster and deploy the .war
          > --- on Unix ---
          > I create a demo domain and wlserver1 using port 7001 and 7002 by the
          > installation program (ip x.y.z.a)
          > --- on NT ---
          > I create a demo domain and wlserver2 using port 7001 and 7002 by the
          > installation program (ip x.y.z.b)
          >
          > --- on Unix ---
          > start the wlserver1 with startWebLogic.sh
          >
          > --- My PC ---
          > go http://x.y.z.a:7001/console
          >
          > create one more server named "wlserver2" using port 7001 and 7002
          > create the cluster named "WLCluster" and fill the the cluster ip
          > "x.y.z.a:7001,x.y.z.b:7001"
          > fill the multi-cast ip 224.0.0.1
          > add the "wlserver1" and "wlserver2" to the "WLCluster"
          > stop the unix WLS
          > start the unix WLS with startWebLogic.sh
          >
          > --- on NT ---
          > start the WLS with startManagedWebLogic.sh wlserver2 http://x.y.z.a:7001
          >
          > --- on Unix ---
          > install the NES 3.6.3 and create a WEB server instance and modify the
          > obj.conf
          >
          > DETAIL
          > ----- start of the obj.conf -----
          > Init fn="load-modules" funcs="wl-proxy,wl-init"
          > shlib="/opt/nes/plugins/weblogic/libproxy.so"
          > Init fn="wl-init"
          > .
          > .
          > .
          > <Object name="weblogic" ppath="*">
          > Service fn=wl-proxy \
          > WebLogicCluster="x.y.z.a:7001,x.y.z.b:7001"
          > </Object>
          >
          > <Object name=default>
          > *NameTrans ...
          > *NameTrans ...
          > *NameTrans ...
          > *NameTrans fn=document-root root="/opt/nes/docs"
          > Service method="(GET|HEAD|POST|PUT)" type=text/jsp fn=wl-proxy \
          > WebLogicCluster="x.y.z.a:7001,x.y.z.b:7001"
          > .
          > .
          > .
          > </Object>
          >
          > <Object name=cgi>
          > .
          > .
          > .
          > </Object>
          > ----- End of the obj.conf ----- (I suppose will redirect all HTTP request
          to
          > WLS from NES)
          >
          > --- My PC ---
          > go http://x.y.z.a:7001/console
          > assign the DefaultWebApp_wlserver1 to wlserver1
          > assign the DefaultWebApp_wlserver2 to wlserver2
          > assign the console the wlserver1 only
          > assign the certificate to wlserver1, wlserver2, WLCluster
          > go SERVER-wlserver1 assign "WLRepGroup1" to Replication Group and
          Preferred
          > Secondary Group
          > go SERVER-wlserver2 assign "WLRepGroup1" to Replication Group and
          Preferred
          > Secondary Group
          >
          > --- on Unix ---
          > go to ./config/examples/applications/examplesWebApp/WEB-INF
          > modify the weblogic.xml
          > go to ./config/examples/applications/examplesWebApp
          > jar cvf myWebApp.war *
          > copy the myWebApp.war to ./config/demo/applications/.
          > and ftp myWebApp.war ro (NT)./config/demo/applicaitons/.
          >
          > --- My PC ---
          > And then now, I can visit http://x.y.z.a:7001/console
          > now I can configuration the myWebApp.
          > assign the myWebApp to wlserver1,wlserver2,WLCluster
          >
          > --- on Unix ---
          > stop the WLS and start with startWebLogic.sh
          >
          > --- on NT ---
          > stop the WLS and start with startManagedWebLogic.sh wlserevr2
          > http://x.y.z.a:7001
          >
          > --- My PC ---
          > visit http://x.y.z.a/myWebApp/SessionServlet (this time no port 7001,
          becoz
          > I want to use the NES web server to proxy the HTTP request)
          >
          > Finally... I can failover the SessionServlet, SnoopServlet and all the
          other
          > html, jsp, servlet, but seems can't load-balancing and Session
          Persistence.
          >
          > Is that anything I did wrong, please comment!
          >
          >
          > with thanks,
          >
          > Alex Wong
          >
          >
          >
          > "Vinod Mehra" <[email protected]> ¼¶¼g©ó¶l¥ó
          > news:[email protected]...
          > > Your configuration looks ok but I guess somehow your clustering is not
          > setup
          > > properly. Check if all the servers are listeniong on the same port and
          > part
          > > of
          > > the same cluster. Also check if you have clustering license.
          > >
          > > Make sure your sessions are of type : "replicated". For that print
          > > the value of session.getClass(), the name will give you an idea. Check
          > > your logs if you got any error message.
          > >
          > > --Vinod.
          > >
          > >
          > > "Alex Wong" <[email protected]> wrote in message
          > > news:[email protected]...
          > > > Dear all,
          > > >
          > > > My Cluster can failover, but can't session replicate....
          > > >
          > > > I start up the 2 WLS 6.0 and the Web Server, then I visit
          > > > http://web_server_ip/myWebApp/SessionServlet serveral times, then the
          > > > counter variable in the session raise up, then I down the "target"
          WLS,
          > > then
          > > > I try http://web_server_ip/myWebApp/SessionServlet now, I can call but
          > the
          > > > counter restart.... so the session seems not yet replicated. what I
          can
          > > > do...?!
          > > >
          > > > My Setup: I setup a Netscape Web Server 3.6.3 as the proxy using
          > > libproxy.so
          > > > with the cluster setting, and use 2 WLS 6.0 (both are running in
          > > 7001,7002)
          > > > as the Application Server Cluster (WLCluster). one WLS is on Unix
          > Machine
          > > > and the other in on a NT. I set the 2 WLSs: the Primary Group is
          > > > "WL_rep_group1", and set the secondary is "WL_rep_group2".
          > > >
          > > > Deployment: I deploy the application "myWebApp" (.war) on the servers
          > unix
          > > > and nt, adn also deploy to the cluster WLCluster.
          > > >
          > > > I deploy the examplesWebApp to my created domain "demo", and modify
          the
          > > > weblogic.xml:
          > > > -------------------
          > > > <weblogic-web-app>
          > > >
          > > > <session-descriptor>
          > > > <session-param>
          > > > <param-name>PersistentStoreType</param-name>
          > > > <param-value>replicated</param-value>
          > > > </session-param>
          > > > </session-descriptor>
          > > >
          > > > <jsp-descriptor>
          > > > <jsp-param>
          > > > <param-name>
          > > > pageCheckSeconds
          > > > </param-name>
          > > > <param-value>
          > > > 1
          > > > </param-value>
          > > > </jsp-param>
          > > > <jsp-param>
          > > > <param-name>
          > > > verbose
          > > > </param-name>
          > > > <param-value>
          > > > true
          > > > </param-value>
          > > > </jsp-param>
          > > > </jsp-descriptor>
          > > >
          > > > </weblogic-web-app>
          > > > ---------------------
          > > >
          > > > so ... anything I did wrong, so the WLS can't do Session
          replication??!!
          > > >
          > > >
          > > > Please Help or Comment!
          > > >
          > > > Thanks in advance!
          > > >
          > > > with thanks,
          > > >
          > > > Alex Wong
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > > >
          > >
          > >
          >
          >

Clustering/Failover/ORB

Hello,
I am trying to make a C++ client to connect to WLS6b2 on Win2000.
Although there is a lack of documentation, I hope I willbe able
to make the example in rmi_iiop work.
Beside that, I was wondering, and please tell me if I am wrong
or not, that with a C++ client using IIOP, we no longer have
load balance and failover if we have a cluster of WLS instances.
Let's me explain, the example shows a C++ client to use the IOR
of the WLS instance, which means I can only connect to this one.
I no longer have the Smart Stub approach in a C++ client case?!
Thank you.
Thierry

Hi,
My comments below.
"Eduardo Ceballos" <[email protected]> wrote in message
news:[email protected]...
Hey!
Thierry Janaudy wrote:
Hi Eduardo,
1. I successfully ran the examples in rmi_iiop yesterday.
Cool. Thank you. (C++, Inprise VisiBroker for C++, WLS6b2)Good. I expect more examples to follow after the GA date. Calling a CORBAserver from within WLS, an SSL example, to name two.
That is really nice. It does save a lot of time having these examples.
>
>>
>>
2. About the clustering stuff, on the client side, the ORB as
you said does not manage anything.What if the IOR had the DNS name of the cluster instead of the IP addressof a single server? The DNS name resolution will round-robbin to another
cluster member every time DNS resolves the name, no?
Okay, it works.
>
>
So your idea about a
special API giving back a set of IORs would be nice, but
you may have to provide more information. What happen
if I create a SFSB on a "Master server", WLS replicates
the content on a "Slave server". If my initial request to
the master fails, from your API, I should be able to know
the IOR of the Slave (which becomes the master), and therefore
be able to re-initiate a connection, and get the remote
reference to the "same" (conceptually) SFSB.
But... hmmm how do I do that?I think if you get the next IOR and narrow it to the SFSB interface youshould be ok.
But this IOR must represent the slave server where the information is
replicated.
Here is an example:
Let's have a cluster or 3 WLS instances, W1, W2, W3
My C++ client gets back an IOR for W1 and create a SFSB, which is replicated
on W2.
From your API, I know that W1 is the master and W2 is the slave.
W1 fails, I get a reference to W2 (Master now), and W3 is the slave. I am
able to
narrow and get the right SFSB.
But now, if I have an IOR with a DNS name, and if I am using DNS routing,
when W1 fails, I may go to W3, and then I have lost my SFSB.
So using DNS/IOR we have the load balance but not the failover.
The IOR API gives us a way to write smart CORBA stub, but we have
to write the code for failover and load balancing.
>
>
Must I store the EJB Handle
(No because it is tied to one app server)..Handle would be alright, too, if it holds the DNS name of the cluster.Okay.
>
>>
Same problem with R/W entity beans (It does not matter for
SLSB and R/O EB)..With entity beans, you need at most once activation, which you will get inthe next release.
Which release are you talking about? WLS 6 FINAL?
>
>>
This API has to be defined in IDL. Or a Remote
Interface from which we can generate IDL anyway...
Yup, either way, you need an API for the C++ client to get a snap shot ofthe list of replicants.
>
>
>>
Here are some thoughts, I have to read the spec for the EJB
Handle.
3. I have found the newsgroup for RMI/IIOP. I have another
question. I would like to do a callback from a SFSB to a C++
CORBA client. Therefore I need and want to store this
reference as a private field of my SFSB... is there any doc
for this particular point?You mean you want the SFSB to call on a CORBA server object that is hostedin the C++ orb, yes? That works, but there's no example, yet. WHat you have
to do is define an RMI interface and RMI server class, generate the WLS RMI
stubs (using weblogic.rmic), and use COS Naming to bind the C++ server
object into the JNDI tree, where the WLS object can look it up. Of course,you don't need to bind servers into the JNDI tree to get this to work, I'm
just suggestion that you try to get this working before you attempt to
integrate the whole thread into EJB, etc.
Yes. I would like a C++ CORBA client to be able to create a SFSB, give it
areference
(in the create method) to a C++ callback object, store this reference as a
private
field of a SFSB. Therefore my SFSB would be able to make calls to this C++
callback object.
Best regards,
Thierry
http://www.mycgiserver.com/~janaudy/

In oracle rac, If user query a select query and in processing data is fetched but in the duration of fetching the particular node is evicted then how failover to another node internally?

In oracle rac, If user query a select query and in processing data is fetched but in the duration of fetching the particular node is evicted then how failover to another node internally?

The query is re-issued as a flashback query and the client process can continue to fetch from the cursor. This is described in the Net Services Administrators Guide, the section on Transparent Application Failover.

Reporting Services as a generic service in a failover cluster group?

There is some confusion on whether or not Microsoft will support a Reporting Services deployment on a failover cluster using scale-out, and adding the Reporting Services service as a generic service in a cluster group to achieve active-passive high
availability.
A deployment like this is described by Lukasz Pawlowski (Program Manager on the Reporting Services team) in this blog article
http://blogs.msdn.com/b/lukaszp/archive/2009/10/28/high-availability-frequently-asked-questions-about-failover-clustering-and-reporting-services.aspx. There it is stated that it can be done, and what needs to be considered when doing such a deployment.
This article (http://technet.microsoft.com/en-us/library/bb630402.aspx) on the other hand states: "Failover clustering is supported only for the report server database; you
cannot run the Report Server service as part of a failover cluster."
This is somewhat confusing to me. Can I expect to receive support from Microsoft for a setup like this?
Best Regards,
Peter Wretmo

Hi Peter,
Thanks for your posting.
As Lukasz said in the
blog, failover clustering with SSRS is possible. However, during the failover there is some time during which users will receive errors when accessing SSRS since the network names will resolve to a computer where the SSRS service is in the process of starting.
Besides, there are several considerations and manual steps involved on your part before configuring the failover clustering with SSRS service:
Impact on other applications that share the SQL Server. One common idea is to put SSRS in the same cluster group as SQL Server. If SQL Server is hosting multiple application databases, other than just the SSRS databases, a failure in SSRS may cause
a significant failover impact to the entire environment.
SSRS fails over independently of SQL Server.
If SSRS is running, it is going to do work on behalf of the overall deployment so it will be Active. To make SSRS Passive is to stop the SSRS service on all passive cluster nodes.
So, SSRS is designed to achieve High Availability through the Scale-Out deployment. Though a failover clustered SSRS deployment is achievable, it is not the best option for achieving High Availability with Reporting Services.
Regards,
Mike Yin
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What is solution of nat failover with 2 ISPs?

Now I have lease line link to 2 ISPs for internet connection. I separate packets of users by accesslist such as www go to ISP1 and mail or other protocol go to ISP2 . Let's say link go to ISP1 down I need www traffics failover to ISP2 and vice versa.
Problem is acl on nat statement?
If you config about this.
access-l 101 permit tcp any any www -->www traffic to ISP1
access-l 101 permit tcp any any mail --> back up for mail packet to ISP2 down
access-l 102 permit tcp any any mail -->mail packet to ISP2
access-l 102 permit tcp any any www --> back up for www traffic go to ISP2
ip nat inside source list 101 interface s0 overload
ip nat inside source list 102 interface s1 overload
In this case is links of ISP1 and ISP2 are UP.
when you apply this acl on nat statement then nat will process each statement in order( if I incorrect please correct me) so mail traffics will match in this acl and then nat with ip of ISP1 only.
please advice solution about this
TIA

Hi,
If you have two serial links connecting to two diff service provider , then you can try this .
access-l 101 permit tcp any any www
access-l 102 permit tcp any any mail
route-map isp1 permit 10
match ip address 101
set interface s0
route-map isp2 permit 10
match ip address 102
set interface s1
ip nat inside route-map isp1 interface s0 overload
ip nat inside source route-map isp2 interface s1 overload
ip nat inside source list 103 interface s0 overload
ip nat inside source list 104 interface s1 overload
ip route 0.0.0.0 0.0.0.0 s0
ip route 0.0.0.0 0.0.0.0 s1 100
In case if any of the link fails , automatically the other traffic would prefer the other serial.
I have not tried the config , just worked out the config on logic .pls go through and try if possible
pls see the note2 column
http://www.cisco.com/en/US/tech/tk648/tk361/technologies_tech_note09186a0080093fca.shtml#related
Hope it helps
regards
vanesh k

Advice Requested - High Availability WITHOUT Failover Clustering

We're creating an entirely new Hyper-V virtualized environment on Server 2012 R2. My question is: Can we accomplish high availability WITHOUT using failover clustering?
So, I don't really have anything AGAINST failover clustering, and we will happily use it if it's the right solution for us, but to be honest, we really don't want ANYTHING to happen automatically when it comes to failover. Here's what I mean:
In this new environment, we have architected 2 identical, very capable Hyper-V physical hosts, each of which will run several VMs comprising the equivalent of a scaled-back version of our entire environment. In other words, there is at least a domain
controller, multiple web servers, and a (mirrored/HA/AlwaysOn) SQL Server 2012 VM running on each host, along with a few other miscellaneous one-off worker-bee VMs doing things like system monitoring. The SQL Server VM on each host has about 75% of the
physical memory resources dedicated to it (for performance reasons). We need pretty much the full horsepower of both machines up and going at all times under normal conditions.
So now, to high availability. The standard approach is to use failover clustering, but I am concerned that if these hosts are clustered, we'll have the equivalent of just 50% hardware capacity going at all times, with full failover in place of course
(we are using an iSCSI SAN for storage).
BUT, if these hosts are NOT clustered, and one of them is suddenly switched off, experiences some kind of catastrophic failure, or simply needs to be rebooted while applying WSUS patches, the SQL Server HA will fail over (so all databases will remain up
and going on the surviving VM), and the environment would continue functioning at somewhat reduced capacity until the failed host is restarted. With this approach, it seems to me that we would be running at 100% for the most part, and running at 50%
or so only in the event of a major failure, rather than running at 50% ALL the time.
Of course, in the event of a catastrophic failure, I'm also thinking that the one-off worker-bee VMs could be replicated to the alternate host so they could be started on the surviving host if needed during a long-term outage.
So basically, I am very interested in the thoughts of others with experience regarding taking this approach to Hyper-V architecture, as it seems as if failover clustering is almost a given when it comes to best practices and high availability. I guess
I'm looking for validation on my thinking.
So what do you think? What am I missing or forgetting? What will we LOSE if we go with a NON-clustered high-availability environment as I've described it?
Thanks in advance for your thoughts!

Udo -
Yes your responses are very helpful.
Can we use the built-in Server 2012 iSCSI Target Server role to convert the local RAID disks into an iSCSI LUN that the VMs could access? Or can that not run on the same physical box as the Hyper-V host? I guess if the physical box goes down
the LUN would go down anyway, huh? Or can I cluster that role (iSCSI target) as well? If not, do you have any other specific product suggestions I can research, or do I just end up wasting this 12TB of local disk storage?
- Morgan
That's a bad idea. First of all Microsoft iSCSI target is slow (it's non-cached @ server side). So if you really decided to use dedicated hardware for storage (maybe you do have a reason I don't know...) and if you're fine with your storage being a single
point of failure (OK, maybe your RTOs and RPOs are fair enough) then at least use SMB share. SMB at least does cache I/O on both client and server sides and also you can use Storage Spaces as a back end of it (non-clustered) so read "write back flash cache
for cheap". See:
What's new in iSCSI target with Windows Server 2012 R2
http://technet.microsoft.com/en-us/library/dn305893.aspx
Improved optimization to allow disk-level caching
Updated
iSCSI Target Server now sets the disk cache bypass flag on a hosting disk I/O, through Force Unit Access (FUA), only when the issuing initiator explicitly requests it. This change can potentially improve performance.
Previously, iSCSI Target Server would always set the disk cache bypass flag on all I/O’s. System cache bypass functionality remains unchanged in iSCSI Target Server; for instance, the file system cache on the target server is always bypassed.
Yes you can cluster iSCSI target from Microsoft but a) it would be SLOW as there would be only active-passive I/O model (no real use from MPIO between multiple hosts) and b) that would require a shared storage for Windows Cluster. What for? Scenario was
usable with a) there was no virtual FC so guest VM cluster could not use FC LUs and b) there was no shared VHDX so SAS could not be used for guest VM cluster as well. Now both are present so scenario is useless: just export your existing shared storage without
any Microsoft iSCSI target and you'll be happy. For references see:
MSFT iSCSI Target in HA mode
http://technet.microsoft.com/en-us/library/gg232621(v=ws.10).aspx
Cluster MSFT iSCSI Target with SAS back end
http://techontip.wordpress.com/2011/05/03/microsoft-iscsi-target-cluster-building-walkthrough/
Guest
VM Cluster Storage Options
http://technet.microsoft.com/en-us/library/dn440540.aspx
Storage options
The following tables lists the storage types that you can use to provide shared storage for a guest cluster.
Storage Type
Description
Shared virtual hard disk
New in Windows Server 2012 R2, you can configure multiple virtual machines to connect to and use a single virtual hard disk (.vhdx) file. Each virtual machine can access the virtual hard disk just like servers
would connect to the same LUN in a storage area network (SAN). For more information, see Deploy a Guest Cluster Using a Shared Virtual Hard Disk.
Virtual Fibre Channel
Introduced in Windows Server 2012, virtual Fibre Channel enables you to connect virtual machines to LUNs on a Fibre Channel SAN. For more information, see Hyper-V
Virtual Fibre Channel Overview.
iSCSI
The iSCSI initiator inside a virtual machine enables you to connect over the network to an iSCSI target. For more information, see iSCSI
Target Block Storage Overviewand the blog post Introduction of iSCSI Target in Windows
Server 2012.
Storage requirements depend on the clustered roles that run on the cluster. Most clustered roles use clustered storage, where the storage is available on any cluster node that runs a clustered
role. Examples of clustered storage include Physical Disk resources and Cluster Shared Volumes (CSV). Some roles do not require storage that is managed by the cluster. For example, you can configure Microsoft SQL Server to use availability groups that replicate
the data between nodes. Other clustered roles may use Server Message Block (SMB) shares or Network File System (NFS) shares as data stores that any cluster node can access.
Sure you can use third-party software to replicate 12TB of your storage between just a pair of nodes to create a fully fault-tolerant cluster. See (there's also a free offering):
StarWind VSAN [Virtual SAN] for Hyper-V
http://www.starwindsoftware.com/native-san-for-hyper-v-free-edition
Product is similar to what VMware had just released for ESXi except it's selling for ~2 years so is mature :)
There are other guys doing this say DataCore (more playing for Windows-based FC) and SteelEye (more about geo-cluster & replication). But you may want to give them a try.
Hope this helped a bit :)
StarWind VSAN [Virtual SAN] clusters Hyper-V without SAS, Fibre Channel, SMB 3.0 or iSCSI, uses Ethernet to mirror internally mounted SATA disks between hosts.

No data in ecc variables in failover mode

Hi all,
got a problem with custom enterprise data layout when CAD is connected to secondary node.
With "set enterprise..." I set a special layout for CAD enterprise data in my script. This works fine as long as CAD is connected to primary node. When CAD is connected to secondary node there is no data in expanded call variales and CAD displays default layout. Changing default layout and writing the content to predefined variables works fine. So it seems only extended call variables are not working in failover mode.
Any ideas?
Br
Sven
(UCCX v8.5)

Hi Sven,
Looks like TAC helped fix the issue. Previously we had rebooted both servers without success. TAC suggested to restart the Desktop Enterprise Service on both servers (I did Pub first than Sub). I've verified ECC variables are being sent to CAD correctly.
The root cause might of been a network outage we had a week ago. We were using the Desktop Workflow Administrator at the time of the outage.
Kyle

Difference between scalable and failover cluster

Difference between scalable and fail over cluster

A scalable cluster is usually associated with HPC clusters but some might argue that Oracle RAC is this type of cluster. Where the workload can be divided up and sent to many compute nodes. Usually used for a vectored workload.
A failover cluster is where a standby system or systems are available to take the workload when needed. Usually used for scalar workloads.

Install Guide - SQL Server 2014, Failover Cluster, Windows 2012 R2 Server Core

I am looking for anyone who has a guide with notes about an installation of a two node, multi subnet failover cluster for SQL Server 2014 on Server Core edition

Hi KamarasJaranger,
According to your description, you want configure a SQL Server 2014 Multi-Subnet failover Cluster on Windows Server 2012 R2. Below are the whole steps for the configuration. For the detailed steps about the configuration, please download
and refer to the
PDF file.
1.Add Required Windows Features (.NET Framework 3.5 Features, Failover Clustering and Multipath I/O).
2.Discover target portals.
3.Connect targets and configuring Multipathing.
4.Initialize and format the Disks.
5.Verify the Storage Replication Process.
6.Run the Failover Cluster Validation Wizard.
7.Create the Windows Server 2012 R2 Multi-Subnet Cluster.
8.Tune Cluster Heartbeat Settings.
9.Install SQL Server 2014 on a Multi-Subnet Failover Cluster.
10.Add a Node on a SQL Server 2014 Multi-Subnet Cluster.
11.Tune the SQL Server 2014 Failover Clustered Instance DNS Settings.
12.Test application connectivity.
Regards,
Michelle Li

Mounted Volume not shwoing up with Windows 2012 R2 failover cluster

Hi
We configured some drives as mounted volumes and configured it with Failover cluster. But it's not showing up the mounted volume details with Cluster Manager, it's showing the details as seen below
Expect support from someone to correct this issue
Thanks in advance
LMS

Hi LMS,
Are you doubt about the disk shown as GUID? Cluster Mount point Disk is showing as a Volume GUID in server 2012 R2 Failover Cluster I creating a mountpoint inside the cluster
and had the same behavior, instead of mount point name we had the volume GUI after volume label, that must by design.
How to configure volume mount points on a Microsoft Cluster Server
http://support.microsoft.com/kb/280297
I’m glad to be of help to you!
Please remember to mark the replies as answers if they help and unmark them if they provide no help. If you have feedback for TechNet Support, contact [email protected]

The Cluster not failover when i shutdown one managed server?

Hello, I created one cluster whit two managed servers, and deployed an application across the cluster, but the weblogic server gave me two url and two different port for access to this application.
http://server1:7003/App_name
http://server1:7005/App_name
When I shutdown immediate one managed server i lost the connection whit the application from this managed server, My question is, the failover and de load balancer not work, why??
Why two diferent address?
thank any help

Well you have two different addresses (URL) because those are two physical managed servers. By creating a cluster you are not automatically going to have a virtual address (URL) that will load balance requests for that application between those two managed servers.
If you want one URL to access this application, you will have to have some kind of web server in front of your WebLogic. You can install and configure Oracle HTTP Server to route requests to WebLogic cluster. Refer this:
http://download.oracle.com/docs/cd/E12839_01/web.1111/e10144/intro_ohs.htm#i1008837
And this for details on how to configure mod_wl_ohs to route requests from OHS to WLS:
http://download.oracle.com/docs/cd/E12839_01/web.1111/e10144/under_mods.htm#BABGCGHJ
Hope this helps.
Thanks
Shail

Want to configure BACKUP VPN in asa 5505 for failover link

Hi,
Current i'm having 2 isps one tata and another one reliance iwant to configure the backup vpn for reliance ip for same peer ip which tata vpn had configured
i mandatory to configure same SA,ENCRPTION,IPSEC POLICY,KEY,LIFETIME...etc for failover vpn also.

Hi michael,
First of thanks for reply.
Can we do it by public certificate or DNS entry e.g. both ISP Public ip address entry will be in DNS and user will hit particular DNS name. You r right that once link down so user will disconnect but when he will retry then he will connect via another link.
Is it possible??
Ashish

CORBA Failover

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