MS Exchange functionality on Linux? Zimbra ties it all together.

The never-ending quest to put a bullet in the Microsoft Exchange server has just chambered another live-round in the form something called Zimbra. To be fair, the Exchange server I manage is very stable, and runs great. I just loath the price of licenses and dread the obscure solutions to seemingly easy tasks.

I don’t know where this product has been hiding, but it caught my eye last week as a result of a Stumble! click. It seems Yahoo! has spent some coin and bought out Zimbra but is continuing to offer the code and binaries under a variety of licensing models. This is all good news for IT departments and service providers everywhere!

There are a number of How-To documents on the Internet that describe implementing various services to support an Exchange’esque environment. I’ve tried it, it works, but it’s ugly and a devil to maintain. Zimbra provides all the necessary technologies in one suite and centralizes the configuration in a uniform interface. The clever folks at Zimbra did it RIGHT. Both the authentication and directory Services are user configurable and 3rd party supported. This means that Zimbra can leverage your existing directory systems such as Active Directory or any other LDAP server for that matter.

I needed to see this in action and judge for myself.

This was a perfect opportunity to use VMWare to stage an image and play around with the basics. I created a 10GB virtual disk and installed Fedora Core 7 x86 while I was downloading the Zimbra 4.5.8GA Binaries for Fedora Core 5 x86 (yes, for FC5). FC7 was installed with minimal options as the Zimbra docs state that services such as httpd, mysqld, slapd, and a few others be either un-installed or disabled. I wasn’t in the mood to fight, so I complied.

Once done, I copied the Zimbra tarball over to the fresh VM, untarred and ran the ./install.sh script. This script does a great job of telling you what you’re missing; in my case I had to add some symlinks for version compatibility in /usr/local for libcurl and libidn. Fetchmail, curl and libstdc++ needed to be installed as well.

I also configured a A and MX record for the DHCP provisioned VM that resolved to private LAN address; all for testing purposes of course. I managed to get Zimbra installed without too much mucking about and went with the default values for the most part. It completed the install and launched the Zimbra services.

Web Client

The web-client is pretty slick, it’s by far the best looking one I’ve yet to see!

It has everything you’d expect in a webclient including a handy search-launch across the top for both internal/Google searches, and built in shared Wiki style document manager. Users can manage multiple identities, POP accounts, Address books… there are lots of variables and settings!

Comparing functionality with that of the Exchange Web client, I don’t notice anything missing, in fact, there’s way more in Zimbra. Even with all the playing around and trying all sorts of options it never hung or crashed my browser; it just plowed through it all.

Web Admin

Like the webclient, the web administration is top-shelf. It offers a ton of configurable items that are often annoying or impossible to do under MS Exchange. For example, under Exchange getting a Resource to auto accept an available booking for something like a meeting room or projector is nuisance; last I checked a Micro$oft DLL was required to hook certain Exchange message and action the resource via script. This functionality is build right into Zimbra.

Spam and AV control; yep. Built right in too.

Separately it would be like managing OpenLDAP, Postfix, Spamassassin, Anomy, ClamAV, stats package, webserver, database, spell-check, CA, and an IMAP server (and more I’m sure)!

Migrating from Exchange seems to be straight-forward. I didn’t get the chance to try, but there are included tools that facilitate the process, mapping MAPI accounts to Zimbra accounts. The tools claim to migrate everything, and based on what I’ve seen so far, there is no reason to doubt this product either.

Given the opportunity (hardware) , I’d love to dedicate an environment to test Zimbra at the office to get an idea of what the day to day operation and maintenance is like and report back on the overall stability and workload.

The system requirements:

Evaluation and Testing
• Intel/AMD 32-bit or 64-bit CPU 1.5 GHz
• 1 GB RAM
• 5 GB free disk space for software and logs
• Temp file space for installs and upgrades*
• Additional disk space for mail storage

Production environments
• Intel/AMD CPU 32-bit 2.0 GHZ+. or large deployments (more than 2000 users), 64-bit OS is recommended.
• Minimum - 2 GB RAM Recommend - 4 GB
• Temp file space for installs and upgrades*
• 10 GB free disk space for software and logs (SATA or SCSI for performance, and RAID / Mirroring for redundancy)
• Additional disk space for mail storage

This is a great product, truly well done, congratulations to all involved!

- Paul