Who uses Zimbra Collaboration Suite and why? [closed]

I deployed the Network Edition of Zimbra about 15 months ago where I work. Zimbra was chosen shortly before I started so I wasn't involved in the evaluation and decision but they were looking for a solution that provided shared calendaring and mobile sync, in addition to email. And a major driving factor was that it wasn't Microsoft. I'm not sure why there is that culture here but for better or for worst I don't think Exchange was even considered due to perceived cost. Zimbra is a very good solution and we just renewed our license for another year.

Pros:

• Calendaring and resource scheduling works well.
• With active sync it is able to push and sync email, contacts, and calendars to our phones.

Cons:

• Task management is not to the level of Exchange/Outlook
• Dealing with attachments from a web client is not as well integrated into your OS like Outlook, so no drag and drop, etc. Their is a zimlet, Zimbra plugin, and Firefox addon that's supposed to allow for drag and drop with attachments but I have not had time to test it yet.
• Web interface only shows 50 emails at a time and that can be a bit annoying. But the advanced search is good and it's fast.
• Some end user training is required or users will to over look functionality that will make the transition easier like advanced search.

Another quick note.
Due to the heavy use of Java and default aggressive MySQL caching settings in Zimbra I would recommend using a system with 4GB of ram even for small deployments like ours. We serve about 50 mailboxes and we originally deployed it with 2GB of ram. In this configuration it was using about 1GB of swap and occasionally the system load would spike and the web client would display an error message saying that the server wasn't responding. Then a minute or so later things would start working again. Upgrading the server to 4GB of ram sorted out the problem.

From research it seems as though the ram requirements do not scale linearly with the number of mailboxes you're trying to serve and that you can easily serve 1000's of mailboxes with 4GB of ram. If you're doing a large deployment then I would talk with the engineers at Zimbra about what the system requirements are for your situation. You can run the different components on different servers and they would be able to help you plan and size the necessary hardware.

I'm glad this question came up because it made me check my server to see what it's uptime and memory use is. It's uptime is 206 days, not bad. But it is using about 1GB of swap currently but without the spikes in the system load or complaints from users of issues. I think I'll wait until I upgrade to 6.0, which is due out any day, to schedule the maintenance and just do a quick reboot before bringing it back online.

We have a pretty large Zimbra (Network edition) setup consisting of a multi-server, multi-site setup with 4 mailbox servers 2 MTAs and an LDAP master which supports about 30,000 users. We also have done our setup entirely on VMware. We also make use of the mobile addon for Windows phone and have the Zimbra connector for Blackberry setup on BES for Blackberry devices.

All-in-all things work very well. Some pros

• One of our primary reasons for using it is to centralize all the data so that users don't have mail floating around on their desktops.
• As a linux administrator, the level of things that we can script on the admin side is fantastic.
• Setup and upgrades are easy, and we have never had an issue arise out of an update

Coming from groupwise, there are some enterprise-type features that are missing (delegating appointments, delayed send, message recall). We also had issues with the migration tool from GW->Zimbra, but that was over a year ago and we are pretty sure at least one of the issues we saw with it was from groupwise's goofy way of doing things. The biggest issue we have come up with is that people in our organization were used to using a "fat" client. When using a web client, there is a different usage pattern and people perceive things as being slower.

There have been a few bugs along the way. Nothing that has been a show-stopper, but annoyances. Their support has been good, but does leave room for some improvement. We started our installation w/ version 4.5 and have kept our installation current. After a year and a half of experience ourselves, we typically end up fixing the problems before support has an answer. On the occasions where we have been completely stuck, support has come through.

We had a custom Courier/Exim setup, but most of our employees use either Outlook 2003 or 2007, and they wanted a shared environment for mail, calendars, and address books. The obvious answer was Exchange, but my boss has had some bad experiences with Exchange, and didn't relish the idea of paying that much for its functionality.

We're running ZCS 6.04 Network Edition for around 60 people, and the transition has been very smooth. Since there aren't a lot of users, I'm doing the migration myself. Installing the Outlook connector, importing items from old PSTs, and using imapsync to copy email from the old Courier server to Zimbra.

Once people start exploring what they can do, they get excited. Finally, they can use their mail, calendar, contacts, and tasks from anywhere, including mobile devices.