Understanding Distributed Data Manager Remote Transactions


Overview

Examples

Included with

Tivoli Problem Management administration

Overview

Understanding remote transactions

A transaction to a remote site is completed successfully when all Tivoli Problem Management related computers, software, and networks in your enterprise are operating properly. A transaction can be a problem transfer to a remote site, attaching a call to a problem at a remote site, viewing all current information about a problem at a remote site, and so on. For more information about the remote transaction types, see the appropriate help topic.

Distributed Data Manager completes transactions to remote sites in the following manner:

  1. Site A packages the data and sends it to Site B.
  2. Site B unpackages the transactions data.
  3. Site B sends an acknowledgement of the completed transaction to Site A. This acknowledgement can represent a successful or failed transaction to Site B.
  4. Site A performs additional tasks based on the success or failure of the remote transaction.

Transactions to remote sites are performed by the Distributed Data Manager application servers in your enterprise using control tables. Control tables are database records that contain the data required to initiate and process transactions to remote sites, as shown in the following table.

Control Table Description
REMOTE_WORK Each record stores the specific data required to perform a particular remote transaction. A REMOTE_WORK record is similar to an Tivoli Problem Management PROBLEM_CLOSURE record.
REMOTE_TASKS A record that is created for each site where a particular REMOTE_WORK transaction is to be performed.
LOCAL_WORK A record that is created by the remote site when it begins the remote transaction. When the remote transaction is completed, the local site is notified. If the local site cannot be notified for some reason, the LOCAL_WORK record is used to notify the local site at a later time.

Examples

Successful transaction

A transaction to a remote site is successful when the following occur:
  1. An analyst at Site A initiates a transaction to Site B.
  2. The Site A application server packages and sends the transaction to the Site B application server.
  3. The Site B application server unpackages the transaction, and performs the associated work.
  4. The Site B application server sends an acknowledgment to the Site A application server.
  5. The Site A application server removes the REMOTE_TASKS record.
Pending transaction A transaction to a remote site is pending (PEND) when the following occur:
  1. An analyst at Site A initiates a transaction to Site B.
  2. The Site A application server packages the transaction and sends it to the Site B application server.
  3. The Site B application server unpackages the transaction and performs the associated work.
  4. The Site B application server is unable to send an acknowledgment to the Site A application server.
  5. The Site A application server labels the REMOTE_TASKS record as pending.
    A network, application server, or database problem at Site B can result in a pending transaction.
  6. The Site B site periodically retries sending an acknowledgment contained in the LOCAL_WORK record to the Site A application server. When the application server at Site B can send the acknowledgment, the transaction is completed by the Site A application server.

Failed transaction 1

A transaction to a remote site fails when the following occur:
  1. An analyst at Site A initiates a transaction to Site B.
  2. The Site A application server packages the transaction and is unable to send it to the Site B application server, or the Site B application server is unable to receive the transaction.
    A network problem, or a stopped or suspended application server at Site B can cause a transaction to fail.
  3. The Site A application server labels the REMOTE_TASKS record as failed.
  4. The Site A application server periodically retries sending the transaction. The exception to this is if Distributed Data Manager at Site A is configured to automatically cancel failed problem transfers to remote sites.

Failed transaction 2

Transactions to remote sites also can fail at the database level, when the following occur:
  1. An analyst at Site A initiates a transaction to Site B.
  2. The Site A application server packages and sends the transaction to the Site B application server.
  3. The Site B application server unpackages the transaction, but is unable to perform the associated work at the database level.
  4. The Site B application server sends an acknowledgment to the Site A site application server that the transaction failed.