Problem:

Messaging Bridge on WebLogic Server 8.1 does not start. Following errors seen in server log:

####<Jan 27, 2010 10:10:13 AM GMT> <Info> <MessagingBridge> <myhost> <managed1> <ExecuteThread: ’4′ for queue: ‘MessagingBridge’> <<WLS Kernel>>
<> <BEA-200032> <Bridge "MyBridge" is configured to disallow degradation of its quality of service in cases where the configured quality of service is unreachable.>
####<Jan 27, 2010 10:10:13 AM GMT> <Error> <MessagingBridge> <myhost> <managed1> <ExecuteThread: ’4′ for queue: ‘MessagingBridge’> <<WLS Kernel>> <> <BEA-200025> <Bridge "MyBridge" failed to start, because the quality of service configured (Exactly-once) is unreachable. This is likely due to an invalid configuration or adapter limitations.>
####<Jan 27, 2010 10:10:13 AM GMT> <Info> <MessagingBridge> <myhost> <managed1> <ExecuteThread: ’4′ for queue: ‘MessagingBridge’> <<WLS Kernel>> <> <BEA-200034> <Bridge "MyBridge" is shut down.>

NOTE: MyBridge connects a WebLogic JMS destination (source) to an MQ destination (target).

Background & Analysis:

In order for Messaging Bridges on WebLogic 8.1 to use Exactly-Once QOS, the following requirements must be met:

• Messaging Bridge adapter must be jms-xa-adp.rar and its JNDI name is eis.jms.WLSConnectionFactoryJNDIXA.
• Connection Factories for source Bridge destinations must be XA-enabled.
• Connection Factories used for target Bridge Destinations must be XA-enabled.
• Messaging Bridges must be configured with Exactly-Once QOS.
• The “QOS Degradation Allowed” checkbox must be unchecked.

With the above, it is recommended that the Messaging Bridges be Synchronous for better performance (fewer transaction commits).

From the log snippet above, you can see that the Messaging Bridge MyBridge could not start because the QOS (Exactly-Once) was unreachable and the Bridge was not allowed to degrade its QOS.

The QOS will typically be unreachable due to adapter, bridge configuration or bridge destination configuration issues as referred to in the log snippet.

Solution:

Enabled XA on the ConnectionFactory for the target Bridge Destination on MQ.

In order to satisfy the Exactly-Once QOS, both source and target destination connection factories must be XA-enabled.

Root Cause:

The ConnectionFactory for the target Bridge Destination on MQ was configured as non-XA, thereby preventing the Messaging Bridge from initiating an XA connection from the WebLogic Bridge destination to the MQ Bridge destination. Since the Messaging Bridge was not allowed to lower its QOS to make the connection, it failed to start properly.

 NOTE: By allowing QOS degradation, the MessagingBridge will connect to the MQ destination even if the ConnectionFactory for the Bridge Destination on MQ were non-XA. However, the choice of QOS must be driven by business requirements and not by technical workarounds.

 Reference: Oracle Documentation

NOTE:
(1) The solution above describes a successful problem-solving experience and may not be applicable to other problems with similar symptoms.
(2) Your rating of this post will be much appreciated. Also, feel free to leave comments.

Problem:

WebLogic Administration Server (with WebLogic Integration) 8.1 does not start. Following errors seen in stdout/stderr/server logs:

####<Jan 25, 2010 4:30:26 PM GMT> <Error> <JDBC> <myhost> <myadmin> <main> <<WLS Kernel>> <> <BEA-001151> <Data Source "cgDataSource" deployment failed with the following error: null.>

####<Jan 25, 2010 4:30:26 PM GMT> <Info> <JDBC> <myhost> <myadmin> <main> <<WLS Kernel>> <> <BEA-001156> <Stack trace associated with message 001151 follows:

weblogic.common.ResourceException

        at weblogic.jdbc.common.internal.DataSourceManager.createDataSource(DataSourceManager.java:264)

####<Jan 25, 2010 4:30:30 PM GMT> <Error> <WLW> <myhost> <myadmin> <main> <<WLS Kernel>> <> <000000> <Failed to obtain connection to datasource=cgDataSource, using generic DB properties>

####<Jan 25, 2010 4:30:31 PM GMT> <Error> <WLW> <myhost> <myadmin> <main> <<WLS Kernel>> <> <000000> <Error in startup class com.bea.wli.store.DocumentStoreSetup Method: init:

java.lang.IllegalStateException: Unable to start DocumentStore:  com.bea.wli.store.DocumentStoreException: Could not find SQL Document Store cgDataSource

            .

            .

Background & Analysis:

WebLogic Integration (WLI) is a software Business Process Integration framework that runs on WebLogic Server. WLI also includes a console application (wliconsole) to manage WLI configuration. This console application is deployed on the WebLogic Administration Server. Since the console application interacts with the database, it uses default data sources and connection pools (e.g. cgDataSource and cgConnectionPool) for database connectivity.

The errors above indicate that the cgDataSource failed to deploy and consequently, a startup class could not obtain connections to the database, thereby failing deployment and preventing the Administration Server from starting.

Data Sources use Connection Pools to obtain database connections.

Solution:

Ensure that the Connection Pool for the cgDataSource is configured properly (correct JDBC driver, URL, credentials, etc.) and targeted/deployed on the Administration Server (not just the cluster).

Root Cause:

The connection pool (cgConnectionPool) for the data source cgDataSource was not deployed on the Administration Server.

NOTE:
(1) The solution above describes a successful problem-solving experience and may not be applicable to other problems with similar symptoms.
(2) Your rating of this post will be much appreciated. Also, feel free to leave comments.

In WebLogic versions prior to 9, JSAFE decryption exceptions and password encryption could be resolved/performed by simply setting plain-text passwords in config.xml as described here.

However, in WebLogic versions later than 9.0, setting plain-text passwords in config.xml (Production mode environments) will throw the following error:

<Critical> <WebLogicServer> <BEA-000362> <Server failed. Reason: [Management:141266]Parsing Failure in config.xml: java.lang.IllegalArgumentException: In production mode, it’s not allowed to set a clear text value to the property: PasswordEncrypted of ServerStartMBean>

So, for WebLogic 9.x+ versions, if you doubt passwords in config.xml, you will need to encrypt plain-text passwords and configure them in config.xml as follows:

STEP 1: Encrypt the password you wish to change in config.xml.

Example: You experience JSAFE exceptions with the password of one of your connection pools and you doubt the encrypted password in config.xml.

• Source the WebLogic environment (to set CLASSPATH and other variables) as follows:

cd <domain-dir>/bin
. ./setDomainEnv.sh

• Encrypt the plain-text password as follows:

cd <domain-dir>
java weblogic.security.Encrypt <password>

STEP 2: Update the config files (config.xml, jdbc, etc.) with the encrypted password obtained above.

NOTE: The above encryption procedure will work even with earlier versions of WebLogic (e.g. 8.1).

I just watched an interesting documentary titled Britain’s Really Disgusting Food hosted by Alex Riley. This documentary exposed the use of MRM in the production of a variety of frozen meat products. The main topic of this documentary was Mechanically Recovered Meat (MRM).

MRM is produced by removing all the good portions of meat (breast, thigh, etc.) and then crushing the remaining skeleton along with connective tissue and fat against a mesh in a mechanical device to produce a pile of crushed bones and and a slurry. The resulting meat slurry is called MRM and is typically used in Hot Dogs, Chicken nuggets and burgers. Also, cheap brand frozen foods (meat pies, kievs, etc.) cost less because they typically use MRM. MRM has been around for a while, but not so well known to the general public.

Alex was able to create a Chicken Kiev that met the FSA requirements, but had only 19% chicken (MRM-type stuff). And he was able to sell the Kievs to rich dudes at a food fair! Alex tried to  get the FSA’s attention with a sarcastic “Eat Waste Save Animals” (by eating rubbish like MRM products, you maximize utilization of an animal, thereby saving the slaughtering of more animals) demonstration in front of the FSA office in London. Check out the video below:

There are other documentaries in this series. You can check them out on YouTube.

Another startling revelation in this documentary was the manner in which most frozen meat products are imported into the UK (and being very cheap). Here’s an example : Chicken slaughtered in Brazil, salted and frozen, then shipped to Netherlands, unsalted and thawed, then injected with water, frozen again and then shipped to the UK. Yikes!

I remembered a pair of American-style Hot Dog (Ye Olde Oak) cans in my Kitchen cabinet (bought them a year ago, but hadn’t consumed them as I’ve been avoiding processed meats). I checked the label and just besides the banner “Highest Quality Hot Dogs”, the list of ingredients read – 60% Mechanically Recovered Chicken, Pork collagen, EXXX, etc……the cans went straight into my dustbin! So, every time you think of popping into that Burger shop around the corner, think about MRM!

If e-reader manufacturers optimize e-readers for reading news (i.e. provide an easy transition from the ubiquitous newspaper), then this would be the first step towards the decline of the newspaper print media and a great stride forward in the digital age. There are several e-readers available, with Amazon.com sparking a lot  of interest with its Kindle. However, all e-readers currently available are not ready to replace the newspaper given their small displays and accessibility to news. With LG’s development of a 19in flexible e-reader (see image below), e-readers can move one step closer towards replacing newspapers.

The future e-Newsreader?:

• Large display e-reader – a bendable, foldable [ collapse into a compact deck of cards? ] display with built in wi-fi, memory, electronic paper , internet access (via mobile service providers) and embedded software.
• An e-news app store to provide lots of cool software to make news reading much more efficient and effective or such software could be bundled with the e-Newsreader you buy.
• You purchase your daily news online (or via long-term subscriptions) and the electronic version of the news is transmitted to your e-Newsreader. The electronic version of the news will still have the same content format and look as today’s newspapers, but in addition, you’ll have several cool features at your disposal – zoom in/out, search, bookmark favourite articles, save to memory, etc. – and all these features via touch screen, stylus and voice-recognition technologies.
• Software will allow you to track a story across several days’ e-news stored in your e-Newsreader’s memory and provide you with a timeline of events.
• The e-Newsreader will be optimized for displaying newspaper-style news, but will also allow ebooks (several formats) to be read.

Pros:

• Save the planet!! e-news will save a huge amount of paper.
• Significant reduction in production costs for media companies (no printing newspapers), thereby allowing e-news to be delivered at lower rates than today’s newspapers.
• No more rushing, queuing and frantically searching for small change to buy your daily newspaper. Get news delivered whenever, wherever.
• No more littering public transport and other places with used newspapers (perhaps free newspapers like “The Metro” for tube/train travellers in the UK may be transmitted to your e-reader if you have a valid ticket).
• Read news far more efficiently. For example, use the search feature to quickly check the stories that you’re following and then move on to other articles.
• Make information and knowledge much more easily accessible to the public. This encourages more research, better journalism and contributes to building knowledge communities.

Cons:

• The decline/demise of the newspaper print industry means the loss of several jobs.
• You’ll miss the several other benefits of newspapers – street food holder, packing, etc.

e-Newsreaders will have a large market in developed countries. Developing countries won’t have a market for such devices unless they come out of poverty (to make such devices affordable to the genral public) and literacy is high (to get people to use such devices).

Amazon.com initially ran into loads of trouble with its Kindle, primarily due to some daft decisions (like catering to only US mobile network technologies, thereby preventing world-wide distribution) and like other e-readers, it’s primarily aimed at reading e-books (although the latest Kindle DX aims to make reading news easier with a larger display. Amazon.com’s framework of using the Kindle with its Whispernet was a step in the right direction, but lack of planning caused them many issues.

Knowledge and information are key to a country’s development and consequently making knowledge and information more easily accessible should be the key driver behind devices such as e-readers. However, for this digital dream to become the common man’s reality, a helluva lot of work has to be done and large organizations and governments must work cooperatively with each other.