Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revision Previous revision
Next revision
Previous revision
doc:sync:english [2007/12/11 04:45]
roshan
doc:sync:english [2010/12/24 09:55]
sarawatson
Line 1: Line 1:
 +
 ====== Synchronization Module ====== ====== Synchronization Module ======
  
-The following scenario will elaborate how the synchronization module will help to transfer information among independent Sahana instances sharing data among different user levels and Sahana installations. 
  
  
-==== Actors ====+===== Introduction ===== 
 +The synchronization module provides important functionality to the overall disaster management process.  Its purpose is to effectively transport the huge amount of data in a particular Sahana installation to another Sahana installation, with merging. 
 + 
 +This capability can be vital, particularly when a disaster destroys the communication infrastructure, preventing relief workers and others from interacting via an electronic telecommunication medium.  In that situation, a manager supporting field operations can obtain the Sahana data from a major disaster management center, and deploy that data into a Sahana instance residing on a laptop or other mobile device or computer, destined for the field.  When the field worker returns to the disaster management center, the cumulative data, including that newly gathered in the field, can be uploaded/synchronized.  As part of synchronization, the receiving Sahana instance in the center will first automatically check the difference between its own database and the uploaded data.  Differences found are extracted, and applied to the main Sahana installation. 
 + 
 +This module helps not only when the communication is limited, but when relief workers want to integrate two different Sahana installations. [Is bi-directional synchronization supported? This achieves consistency and allows teams to work as if they are using one database.  Scenario-based guidelines for the synchronization module can be found 
 + [[http://wiki.sahana.lk/doku.php?id=doc:sync:english&rev=1193907698|here]]. 
 + 
 +This module can be helpful when cloning a database of [[http://cvresumewritingservices.org/professional-resume.php|professional resume services]].  (Another alternative: the Snapshot module.) 
 + 
 +== Coming Soon == 
 +New work on the Synchronization of Sahana Servers via peer-to-peer (P2P) transport is being undertaken as part of the Google Summer of Code 2009 by student Hasanat Kazmi and mentor Fran Boon.  A [[http://trac.sahanapy.org/wiki/BluePrintSynchronisation|conceptual blueprint]] is being refined, and the choice of technology and form are under active discussion. 
 + 
 + 
 + 
 + 
 + 
 +===== Getting Started with the Synchronization Module ===== 
 + 
 +Click on the **Synchronization** link in the Sahana Main menu.  The Synchronization Module menu will then appear above the Main menu. 
 + 
 +{{ doc:sync:diagram1.png?800 }}  
 + 
 +===== Synchronization Menu ===== 
 + 
 +**__Home__** 
 + 
 + 
 + This link directs the user to the Synchronization module main window. 
 + 
 +**__Export Data__** 
 + 
 +Using this link, the user can get a copy (i.e., a "data dump") of the Sahana database or a part of it.  The **Export Data** window contains three tabs, **Select Data**, **File Type**, and **Compression Type**, to specify what type of data copy is desired.  After applying the appropriate settings, click on the Export button, and indicate where to save the file. 
 + 
 +**NOTE :** Before clicking on the Export button, make sure to navigate through all 3 tabs.   Otherwise, the default settings will be applied to your data copy, which may not match your expected purpose. 
 + 
 + 
 +**Select Data.** The user can choose the data required from the Sahana database. The database content has been divided into several categories, from which one can select a subset or (with the **Select All** button) all categories.  The **Clear** button removes all the check-marks. 
 + 
 +{{ doc:sync:selectdata.png?800 }} 
 + 
 +**File Type.** The type of the file desired for the data copy.  First consider the planned transfer media and intended use, then choose the appropriate type.  "CSV" means "comma-separated values", and is often best if transferring to non-Sahana applications. 
 + 
 +{{ doc:sync:filetype.png?800 }}  
 + 
 + 
 +**Compression Type.** When the data copied is huge, uncompressed transfer can be time-consuming and in other ways difficult.  If you anticipate this, apply compression to save much time and file space. 
 + 
 +{{ doc:sync:compressiontype.png?800 }} 
 + 
 + 
 +**__Import Data__** 
 + 
 +Simply browse and select the data file to be imported (obtained from another Sahana installation, by **Export Data**, as described above) and click OK.  Then click on the **Next** button and in the next window click on the **Import** button.  This action will inspect the differences between the database and data copy (dump file) and update the database as mentioned in the Introduction section. 
 + 
 +If instead the user wants to erase all the data in the database and fill the empty database using the dump file data, click on the **Advance Option** link to the left of the **Import** button  and select **Yes** (default is No).  Then click **Import**. 
 + 
 + 
 +{{ doc:sync:import.png?800 }} 
 + 
 +{{ doc:sync:import2.png?800 }} 
 + 
 +{{ doc:sync:advance.png?800 }} 
 + 
 + 
 + 
 +**__History__** 
 + 
 +This shows details about the imported dump files, and allows an overview about the state of the database and how often the data is synchronized between different Sahana installations. [[http://www.huglaw.com/marijuana-possession-attorney-drug-possession-marijuana-sale-attorney-albany-troy-schenectady-saratoga.html | Marijuana Lawyer Albany]] 
 + 
 +{{ doc:sync:history.png?800 }}  
 + 
 + 
 +**NOTE :** All the activities mentioned above can be done by using the links on the Synchronization home page. 
  
-  * **System administrator**  This could be the Sahana Administrator or a person who has special access to the synchronization module. +[[http://impact-resumes.net/sample-resumes/career-change-resume.htm | Professional Career Change Resume Samples]]
-  * **Data carrier** :  This could be a field officer who has a laptop or a person who carries a data in a removable media. +
-  * **Field Officer** :  This is a person who has either a laptop or a palm top on which a Sahana instance is running.+
  
  
  
 + 
  
  
-==== Scenario ==== 
  
-**Entering default data to the system and sending them to the field officers** 
  
-  -  The system administrator install Sahana in the main server at the head office. 
-  -  Then he enters all the location details and the other default data in to the system ( It is recommended to use main server's location details in configuring field level implementation of the systems. This is not a must, how ever this will reduce mismatch among different server instances. See here for more details [[doc:locationmore:english]]). 
-  -  Then the administrator will take an export from the system using the Synchronization module export facility. This export file will contain all the default data and the location details. 
-  -  Then a Data carrying officer can deliver that file to the field officers. The most easy way is to use a USB disk or if the connectivity is there they can e-mail the file to the field officers. Also if the field officers have access to the central server they can get a data dump (a special file containing tables and data from a database for back up and restoration purposes) by themselves. 
-  -  Once field officers have the default data dump they can set up a Sahana instance ( Field instance) in their computer and upload the default data dump to that instance. To upload a data dump use the import facility provided in the synchronization module. 
-  -  Now the default data and the locations will be available in the field instances. Further more, field offices can add more sub locations (see here [[doc:locationmore:english]] ) and default data to meet their requirements.  
-  -  Then field officers can collect data in to their Sahana Instances. 
  
-**Gathering collected data on the field in to the main server.** 
  
-  - After collecting data, the field officers can get a data dump and send the dump file to Headquarters to upload to the main Sahana Server. 
-  - Further more field officers can use the same instances to collect more data and to update the existing data in them. 
-  - Once they get an opportunity they can get a dump of updated and new data and send them to the Headquarters. 
-  - When you upload a dump containing an updated data the system will update the database with the new values in the dump file. Also if there are new records the system will insert them to the database.  
  
-**__Scenario Example __** 
  
-The following picture shows an example of a data exchange scenario. 
  
-{{doc:sync:synchronization_scenario.png|Sync Scenario}}+ 

Navigation
QR Code
QR Code doc:sync:english (generated for current page)