I configured a message processor in ESB WSO2. every now and then, all the messages are not carried out and they stay pending in the queue (message broker)
I can I can find only this log in the ESB console
"BlockingMessageSender of message processor [SAPMoveMaterialMessageProcessor] failed to send message to the endpoint"
My questions:
1, how and where can I see the real reason (detailed logs, error msg) why the message processor could not be sent out? I have defined a Fault sequence on the message processor but shows nothing
2, in case that I get this issue in the production environment is there a way how to "copy" a pending message (from the message broker queue) to my DEV environment and debug it there?
thank you very much for your ideas!
AFAIK you can get more details from enabling DEBUG logs related to message processors. You can get these in the server management console tools- >'logging' and doing a search for matches which contains 'messageprocessor' and make the log level to DEBUG.
eg:
org.wso2.carbon.message.processor.service.MessageProcessorAdminService
org.wso2.carbon.message.processor.MessageProcessorServiceComponent
As a solution for this you can try out by using a clone mediator (the use of clone mediator here is to make multiple identical copies of the message) inside the fault sequence (when pending message gets fail to consume) to persist to a database - may be to your dev environment.
Related
I am implementing an IMAP server, operating on messages shared with other systems and due to business needs users are not allowed to create or delete messages or mailboxes via the IMAP server.
In our production environment however, we often see the following three commands occur very often
15 EXAMINE "Drafts"
16 STATUS "Drafts"
17 CREATE "Drafts"
For all three we reply with a NO response, but when the user logs in again next time, we see the same commands being issued.
Is there a way to discourage the client from issuing these commands? The only folder that we have is INBOX.
In principle, a response code of CANNOT ("The operation violates some invariant of the server and can
never succeed") should get the message across, though I suspect few clients would react appropriately to such feedback.
I've got a rebus server process running on one machine and an MVC website on another. I configure the message routing in the MVC website with a local input and error queue and the destination pointing to the queue myinputqueue#BusServer and when it runs it sends the subscription message without error but nothing seems to appear on the destination queue. The receiving bus never acknowledges it or creates a subscription entry.
It's using msmq as the transport and all queues have full permissions to the Everyone group.
I'm assuming I've not configured something correctly so I hope this is the right forum to raise the question.
Appreciate any help.
Even though Everyone has access to the queues, and that sounds like there's nothing in the way of communicating freely, I'm not sure that it works that way.
In any case, I suggest you make sure your IIS app pool is runnig with some dedicated service user identity, which you can also use as the user account under which your server process is running.
With MSMQ, messages are never lost - so in your case, the subscription message is most likely sitting in an outgoing queue on the web server machine, or it might have been moved to the "Transactional dead-letter queue" which is where MSMQ ends up moving stuff that it cannot find a place for.
Could you try and take a look at the outgoing MSMQ queues and/or the transactional dead-letter queue to see if it's a user rights problem that is haunting you?
I am running a Windows Service on a Windows Server 2003 R2. We are using Exchange Server to send out the emails.
I am using log4net.dll 1.2.11.0.
I have situation where log4net sometimes sends emails and sometimes don't eventhough no changes has been made to the set up.
All the other log4net logging works very fine. And as said sometimes the application sends out emails and some times it don't, having made no change to the application.
All my methods are in try-catch clauses, but I don't get any errors.
When I run the the Windows Service on my local machine, the log4net email always works, and as said on the remote server, sometimes the log4net email works, sometimes it don't, having made no changes to the setup.
I am using log4net.Internal.Debug and have a System.Diagnostics.TextWriterTraceListener file where stuff is written to.
Scanning thorugh this file I haven't noticed anything in particular, but I don't know what specific to look for.
Any ideas about what the problem is or what to do?
If the SMTP appender cannot send an email it would log an exception with this text: Error occurred while sending e-mail notification. This would be visible if internal debugging is enabled. Maybe you have filters or something like that configured that prevents log4net from sending an email.
You could download the source code of log4net and add extra logging to the SMTP appender to find out if the "SendMail" method of the appender gets called at all. If it does and no email and no error is shown, then we need to assume that the exchange server somehow swallows the emails. If the appender is not triggered, then you need to review your filter / buffer / threshold configuration.
Alternatively you could try to use the SmtpPickupDirAppender.
we're using CometD 2 to achieve the connection between a central data provider and several backends consuming the data. Up to now, when one of the backends fails briefly, all messages posted in the meantime are lost. Now we heard about the "Acknowledge Extension" for CometD. It is supposed to create a server-side list of messages and delivers them when one of the clients reports to be back online. Here are some questions:
1) Does this also work with several clients?
2) The documentation (http://cometd.org/documentation/2.x/cometd-ext/ack) says: "Note that if the disconnected browser is disconnected for in excess of maxInterval (default 10s), then the client will be timed out and the unacknowledged queue discarded." -> does this mean that in case my client doesn't restore within the maxInterval, the messages are lost anyway?
Hence,
2.1) What's the maximal maxInterval? Which consequences does it have to set it to a high value?
2.2) We'd need a secure mechanism for fail outs of at least a few minutes. Is this possible? Are there any alternatives?
3) Is it really only necessary to add the two extensions in both the client and cometD server? We're using Jetty for the server and .NET Oyatel for the client. Does anyone have some experiences with this?
I'm sorry for this bunch of questions, but unfortunately, the CometD project isn't really well documented. I really appreciate any answers.
Cheers,
Chris
1) Does this also work with several Clients
Yes, it does. There is one message queue allocated for each client (see AcknowledgedMessagesClientExtension).
2) does this mean that in case my client doesn't restore within the maxInterval, the messages are lost anyway?
Yes, it does. When the client can't reach the server for maxInterval milliseconds, the server will throw away all state associated with that client.
2.1) What's the maximal maxInterval? Which consequences does it have to set it to a high value?
maxInterval is a servlet parameter of the Cometd servlet. It is internally treated as a long value, so the maximal value for it is Long.MAX_VALUE.
Example configuration:
<init-param>
<!-- The max period of time, in milliseconds, that the server will wait for
a new long poll from a client before that client is considered invalid
and is removed -->
<param-name>maxInterval</param-name>
<param-value>10000</param-value>
</init-param>
Setting it to a high value means that the server will wait longer before throwing away the state associated with a client (from the time the client stops contacting the server).
I see two problems with this. First, the memory requirements of the server will potentially be higher (which may also make denial of service easier). Second, the RemoveListener isn't called on the Server before the maxInterval expires, which may require you to implement additional logic that differentiates between "momentarily unreachable" and "disconnected".
2.2) We'd need a secure mechanism for fail outs of at least a few minutes. Is this possible? Are there any alternatives?
Yes, it is possible to configure the maxInterval to last for a few minutes.
An alternative would be to restore any server side state on every handshake. This can be achieved by adding a listener to "/meta/handshake" and publishing a message to a "/service/" channel (to make sure only the server receives the message), or by adding an additional property to the "ext" property of the handshake message. Be careful to let the client restore only valid state (sign it on the server if you must).
3) Is it really only necessary to add the two extensions in both the client and cometD server?
On the server it is sufficient to do something like:
bayeux.addExtension(new AcknowledgedMessagesExtension());
I don't know how you'd do it on Oyatel. In Javascript it suffices to simply include the extension (dojo.require or script include for jQuery).
When a client with the AckExtension connects to the server, a message similar to the following will be logged (from my Jetty console log):
[qtp959713667-32] INFO org.cometd.server.ext.AcknowledgedMessagesExtension - Enabled message acknowledgement for client 51vkuhps5qgsuaxhehzfg6yw92
Another note because it may not be obvious: the ack extension will only provide server to client delivery guarantee, not client to server. That is, when you publish a message from the client to the server, it may not reach the server and will be lost.
Once the message has made it to the server, the ack extension will ensure that all recipients connected at that time will receive the message (as long as they aren't unreachable for maxInterval milliseconds).
It is relatively straightforward to implement client-side retrying if you listen to notifications on "/meta/unsuccessful" and resend the message (the original message that failed is passed as message.request to the handler).
I have created a WCF service using the NetMsmq binding for which i created a private queue on my machine and executed the project. This works fine as such and my WCF service is started and accesses the message using the queue in the debugging environment. Now, I wanted to host the service using the windows service and for the same I created a new project and windows installer as well (This service runs under Local System Account). Then I tried installing this windows service using the InstallUtil command through the command prompt. When installation is happening and during the service host opening, I get an exception saying:
There was an error opening the queue. Ensure that MSMQ is installed and running, the queue exists and has proper authorization to be read from. The inner exception may contain additional information.
Inner Exception System.ServiceModel.MsmqException: An error occurred while opening the queue:Access is denied. (-1072824283, 0xc00e0025). The message cannot be sent or received from the queue. Ensure that MSMQ is installed and running. Also ensure that the queue is available to open with the required access mode and authorization.
at System.ServiceModel.Channels.MsmqQueue.OpenQueue()
at System.ServiceModel.Channels.MsmqQueue.GetHandle()
at System.ServiceModel.Channels.MsmqQueue.SupportsAccessMode(String formatName, Int32 accessType, MsmqException& msmqException)
Could anyone suggest the possible solution for the above issue? Am I missing any permissions to be set for the queue as well as the windows service, if so could you suggest where should these permissions be added?
Tom Hollander had a great three-part blog series on using MSMQ from WCF - well worth checking out!
MSMQ, WCF and IIS: Getting them to play nice (Part 1)
MSMQ, WCF and IIS: Getting them to play nice (Part 2)
MSMQ, WCF and IIS: Getting them to play nice (Part 3)
Maybe you'll find the solution to your problem mentioned somewhere!
Yes, it looks like a permissions issue.
Right click on your private queue from the Server Manager, and select Properties. Proceed to the Security tab, and make sure you have the right permissions in there for your Local System Account.
This is also confirmed in Nicholas Allen's article: Diagnosing Common Queue Errors, where the author defines the error code 0xC00E0025 as a permissions problem.
I ran into same problem, here is the solution.
Right click "My Computer" --> Manage. In Computer Management window go to "Services and Applications --> Message Queueing --> ur queue", select ur queue and access properties. Add the user running ur WCF application and give full access. This should solve the issue.
Can simple be that the service can't find the it's queue.
The queue name must exact match the endpoint address.
Example:
net.msmq://localhost/private/wf.listener_srv/service.svc
points to local queue
private$\wf.listener_srv\service.svc
If queue name and endpoint are according to each other, then is most like that the credentials defined on the IIS pool don't grant access to the queue.