In planning a Linux client migration for mobile (laptop based) users, you can 

expect that selection of a Linux based messaging client to replace a MS 

Windows based client will be the single most important design decision in your 

mobile desktop application migration strategy. The challenge of providing for a 

functionally equivalent (or acceptable) messaging application that supports 

offline use is another reason that inclusion of notebook based users can 

increase the complexity of a migration. (See the  Planning Tip  in 4.6,  Desktop 

vs. notebook considerations  on page 76.) 

There are Linux based messaging client options that provide for offline access 

modes. Mozilla Thunderbird is one example. Thunderbird supports both POP 

and IMAP protocols. More information about Thunderbird can be found here:

http://www.mozilla.org

Although Thunderbird will support offline messaging modes, it does not provide a 

way to integrate calendaring and scheduling functionality into the messaging 

client the way systems such as MS Exchange/Outlook and IBM Lotus 

Domino/Notes do. For this reason, we choose to demonstrate use of Novell's 

Exchange Connector 2000 combined with the Novell Ximian Evolution e mail 

client in Chapter 6,  Client migration scenario  on page 113. Extending the 

example migration scenario in Chapter 7,  Integration how tos  on page 133, for 

the notebook user means that you will also have to test and evaluate the offline 

capabilities of that Novell based solution.

Offline files

As every user to some extent creates and manages her own files and folders, it 

follows that the notebook user should be able to access copies of her files in 

offline/disconnected mode. And the primary storage location for those same files 

should be a regularly backed up and highly available server.

For example, Microsoft provides methods for automatic synchronization of files 

between servers and mobile clients. One of these methods uses the 

Briefcase

, a 

special folder in which one had to put the files that should be synchronized. A 

second method was provided with the launch of Windows 2000/XP, where a new 

function called 

offline files

 was implemented. This mechanism is able to 

synchronize whole folders, and while the notebook is offline, the files are fully 

accessible. Changes are retransmitted after connecting to the network 

automatically. 

In Linux, there is no direct equivalent for this kind of server to client file 

synchronization built into the operating system itself. Instead, the task of 

developing and supporting Linux based file synchronization services between 

client and server is left to ISVs. For example, Novell is offering a new solution for 

taking files offline and sharing them with other users. The product is called 

80 

Linux Client Migration Cookbook   A Practical Planning and Implementation Guide for Migrating to Desktop Linux