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  1. Application Server 3 4 5 and 6
  2. JBAS-4455

LoadBalancePolicy that tries to pin all requests associated with a tx to one server

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    Description

      The HA proxies don't allow failover once a tx has reached a server. This can lead to this kind of situation:

      EJB A deployed on nodes 1 and 2.
      EJB B deployed on nodes 1 and 2.

      1) Start tx, invoke on A.1.
      2) Lookup B.
      3) Invoke on B. LB policy picks B.2
      4) Node 2 is dead for some reason so call fails.
      5) Can't fail over because tx context won't allow a failover after a call has reached a server.

      But, B.1 is fine and is running on the only node the tx has invoked on.

      Approach to improving this. This is based on JRMPInovkerProxyHA methods, but the idea is generic:

      In invocationHasReachedAServer, instead of storing null as the value, you store the target (key is the tx).
      In invoke, if there's a tx, you add that target (if there is one) to the invocation as transient metadata
      The LB policy gets passed the invocation as an arg when it chooses a target (this is already in the API)
      LB policy checks for the metadata. If there, and that target is in its target list, return that target

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          is blocked by

          Bug - A problem that impairs or prevents the functions of the product. JBAS-4950 Transaction failover authorisation is broken within UnifiedInvokerHAProxy

          • Critical - To be worked on immediately following BLOCKER issues.
          • Closed

          Bug - A problem that impairs or prevents the functions of the product. JBAS-4964 txFailoverAuthorizations should be keyed on transaction propagation context

          • Major - To be worked after higher priority work items are addressed. When the severity is high and the effort to change it is low to moderate, this term is chosen. Issues in this category likely have an existing workaround but implementation or execution may be non-trivial.
          • Closed

          Bug - A problem that impairs or prevents the functions of the product. JBAS-5074 MarshalledInvocation constructor should copy over all invocation attributes

          • Minor - To be worked after urgent, high, and medium priorities are resolved. This term is chosen when the severity of the issue is low, or the complexity or effort to correct it may be higher, relatively speaking. For low priority issues, known workarounds exist or are not needed due to the trivial effort needed to address the issue.
          • Closed
          is incorporated by

          Feature Request - Feature requests from customers and/or users JBPAPP-546 JBAS-4455 - LoadBalancePolicy that tries to pin all requests associated with a tx to one server

          • Major - To be worked after higher priority work items are addressed. When the severity is high and the effort to change it is low to moderate, this term is chosen. Issues in this category likely have an existing workaround but implementation or execution may be non-trivial.
          • Resolved
          relates to

          Feature Request - Feature requests from customers and/or users EJBTHREE-1141 LoadBalancePolicy that tries to pin all requests associated with a tx to one server

          • Major - To be worked after higher priority work items are addressed. When the severity is high and the effort to change it is low to moderate, this term is chosen. Issues in this category likely have an existing workaround but implementation or execution may be non-trivial.
          • Resolved

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              rh-ee-galder Galder Zamarreño
              bstansbe@redhat.com Brian Stansberry
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                Updated:
                Resolved: