Linux boffs: Remote access, calendar/address book sharing?

[Farren]

I've got a client using MS Outlook to access mail from a Debian box running Postfix. They took this route because of the cost implications of a groupware package like MS Exchange and Server 2003, but they're getting increasingly demanding.

First they wanted external access. Not wanting an open relay or complicated configuration if one of their users was in an Internet cafe in Hong Kong, I implemented webmail (Squirrelmail).

Almost immediately after that they asked for a solution to share address books between London, Johannesburg and New York. I implemented a short term fix in the form of a VBA macro on their Outlook which runs on startup and imports to a global address book from a spreadsheet on the server, which they can update or share with other cities.

I know the right solution for this is actually LDAP, but I'm not 100% sure how easy it is to implement and whether there are special considerations when several offices are using it across the internet. Can someone shine a little light on it for me before I have to do a whole lot of reading?

My second query is about calendar sharing. My understanding is that you can't do this via LDAP, but someone I spoke to said I should look into OpenExchange. Is this the right route to go? Are there any others. I'm looking for the simplest, most hassle-free route.

[squian]

At some point, commercial software is worth paying for. When I was running the servers for a startup some years back, I got sick of solving all the integration headaches myself and demanded we move up to CommuniGate Pro. It has everything we needed from IMAP and WebMail to decent spam filtering. Today it also has Calendaring and could be a good choice for your users. Of course, cost may still be a problem.

I just set up OpenLDAP for my local network. In general, it is the standard for directories such as address books; however, different applications think different information should be in an address book. Specifically, Outlook has a schema that it expects. So as you go through setting up LDAP, make sure you include the right schema (the OpenLDAP FAQ is useful for this). Once installed and populated, it is pretty easy to connect Outlook users to the LDAP directory.

There are many security options. For my home use, I did not even bother with SSL -- it's all behind my Internet router. For you SSL may be useful -- you may or may not want to allow public access to the directory. Also, you can control which users have access to which data. Typically, you want people to only update their own entries.

The issue of calendar sharing can be very complex. I urge you to find out more about what the end-users are trying to accomplish. In some cases, not even Exchange is sufficient. A couple years ago, I had to build a custom web application to support resource scheduling because Outlook could not show me the right information. Eventually, my company consolidated Exchange servers and we decided to forgo the advanced functionality in favor of tighter integration.

You might consider a hosted solution. Let someone else deal with the headache of web-based views and Outlook integration. But then we are getting back to solutions that have a cost.

Hope that helps.

[Farren]

Thanks a ton Squian. That is really helpful