VMware Zimbra vs. Microsoft Exchange

Introduction

In this post I would like to propose the idea that VMware Zimbra Collaboration Server can serve as a drop-in replacement for Microsoft Exchange in Enterprise environments of all sizes. I would also propose that Zimbra is better suited for multi-tenant ISP deployments than Exchange. Let's discuss the pros and cons of Zimbra and give you the background to consider Zimbra for your next e-mail deployment or customer engagement.

Background

Technically, VMware Zimbra is part of VMware's End-user Computing catalog, but I would also consider it as a good example of a Tier-1 application, once deployed. E-mail is becoming so critical to the operations of any size business that it needs to be designed, implemented and maintained with the same level of care as any other Tier-1 app.

Benefits Overview

That said, the ease with which backup and restore can be performed in Zimbra far outweighs the capabilities of Exchange. A good backup/restore strategy is one of the cornerstones of any Tier-1 app deployment worth its salt. Add to that the fact that Zimbra has orders of magnitude better scaling capabilities than Exchange, all at about 50% of the price, on average.

Storage Benefits

Combine Zimbra with NetApp storage platforms and technologies and you will see even more efficiences around the storage required for backup, attachments, etc. (using NetApp's deduplication technology) in addition to ease of management. Snapshot technologies allow quick backups of e-mail and attachment data resulting in quick restoration when you run into issues. Cloning technologies (FlexClone) will allow you to reduce time required for upgrades by allowing staff to test upgrades with a live copy of recent production data. Replication technologies (SnapMirror) will allow you to move data backups to remote locations for disaster recovery or remote backup facilities for compliance purposes.

General Comparisons

Here are some other comparisons that can be drawn between the 2 platforms:

Key Features	Exchange 2010	ZCS 7.x
Platform Architecture	Core architecture "Extensible Storage Engine (ESE)" is over 20y old and is a non-modular .edb file which doesn't separate message and metadata, so is not conducive to tuning. Database availability group (DAG) uses components with a DNA based on Windows failover clustering, but has yet to be proven for large deployments.	Modular architecture offers Web 2.0 features and cloud scalability. Message and metadata are separated to allow granular tuning and optimization flexibility.
Platform Reliability & Robustness	Microsoft is considering moving the storage engine to SQL Server. Microsoft has yet to prove the robustness of the new architecture.	ZCS leverages a Linux-based operating environment for greater levels of robustness using proven open source components. Uptime measured in years instead of weeks.
Platform Scalability	Exchange doesn't support the use of tiered storage, so adding more users is more costly than in Zimbra.	ZCS supports storage tiers and can scale to millions of users at lower cost.
High Availability	DAG only provides mailbox protection, not protection for the Exchange infrastructure. DAG has a learning curve and only applies to Exchange.	ZCS in conjunction with SRM is a proven, scalable and effective high availability solution. Companies can leverage their existing HA/DR solution with ZCS.
Platform Extensibility	Recommendation is to use Microsoft's proprietary shell. SOAP API has limited server access. Outlook add-ins require significant developer effort and are difficult to support.	SOAP API allows server access. Uses the web services framework for client access and Zimlets for integration with 3rd-party services.
Platform Openess	Microsoft is a closed ecosystem. Developers cannot change or extend platform or APIs.	Based on open source code and extensible using open source programming languages.
Support of Open Standard Protocols	Limited support for the SOAP protocol. No support for REST, CalDAV, CardDAV and ICS.	Support of open standard protocols such as SOAP, REST, CalDAV, CardDAV and ICS.
Rebranding	Outlook Web Access has only a single theme in Exchange 2010, so users cannot switch between themes.	Complete re-branding of the client is possible. Ajax web client has feature parity with the desktop client.
Web-client End-user Access	Limited browser support for OWA.	Rich Ajax/HTML web client is supported on a broad range of browsers and platforms.
Mac Desktop	Parity with Outlook.	Zimbra's desktop client is supported with Mac OS X and has feature parity with the web client.
Linux Desktop & Server	No Outlook client for Linux. No Exchange server for Linux.	Zimbra desktop functions on Linux and has complete feature parity. ZCS server components love the Linux platform.
Mobile Support	Fully supports push using Microsoft's ActiveSync technology.	Supports ActiveSync push for calendaring and e-mail.

vSamurai's Take

Zimbra has been a passion of mine since I started using it back in 2006-2007. My previous company had evaluated implementing Exchange, Zimbra and a couple of other solutions. Due to our IT management and staff being huge proponents of Open Source, we decided on the Zimbra solution. I am very glad that we did. To be honest, despite the fact that we had users who were used to the Outlook client, we didn't have much pushback when we moved to Zimbra as it has full feature parity with Exchange. I expect that your results may be the similar if Zimbra is given a serious look for new e-mail implementations or during hardware/software upgrade cycles in pre-existing implementations of Exchange.

Expect to hear more soon about the ins and outs of deploying Zimbra in your or your customer's environment. SaaS is here and this is just one part of VMware's End-user computing strategy, so look for more in the future from them as well.

Update on Wednesday, February 29, 2012 at 6:04PM by Christopher Wells

Thanks go out to Jim Millard who had a good point on Twitter, which is that I forgot to compare ActiveSync capabilities between Exchange and Zimbra. Well, the good news is that Zimbra Network Edition fully supports ActiveSync capabilities for push of e-mail and calendar appointments.

I use it everyday, in fact, between a Zimbra e-mail account I have set-up in 01.com's zMailCloud and my iPhone 4. You configure it just as you would an Exchange account on the iPhone (see here). I receive meeting requests that can easily be added to my calendar with automatic reminders as well. You can also deploy Zimbra to work with Blackberry Enterprise Server.

To be sure, these features are only available with the paid Network Edition of Zimbra, however, they are still much less costly than Exchange. Based on my experience, I believe the mobile functionality to at least match that of Exchange, however, I recommend that you look at doing a PoC and ultimately make that decision on your own as your results (as with everything) may vary.

Comments

[Arjan]

Hi Christopher,

Great post! Sadly most of the time in my working experience the only Zimbra I've seen was on the MacBooks of the VMware PSO consultants ;-)

I think your comparison is an eye opener, and I'll shout out to this post as quick as I hear anyone thinking about an upgrade/replacement for Exchange.

Greetz,

Arjan

[Josh Atwell]

Great post as usual! You forgot the most important category though! PowerShell integration! Going to Zimbra doesn't mean you have to let go of managing your email environment with PowerShell! :)

http://gallery.zimbra.com/type/extra/zimbrapowershell

[Christopher Wells]

@Arjan

Thanks for the comment. I hope this will help to jump-start the conversation regarding the merits of Zimbra. Good luck!

[Christopher Wells]

@Josh

My section on API integration is probably a bit dated, but to be honest I hadn't checked about integrations with PowerShell, but it figures they'd have something thanks for letting me know and getting the word out!

[Jenu]

Just a point on Platform Scalability: With Exchange 2010, you can deploy it on lower end drives because the IOPS requirements are much lower than the previous versions of Exchange. So there isn't a need to introduce a tiered storage architecture; you can deploy it on higher density, lower end cheaper drives.

[Roberto]

I did a Groupwise to Zimbra migration last summer. Overall, I rellay like the product, their support is where I was turned off. Anytime I had an issue, I'd have to go through a web portal and wait 2 days before hearing from support. This would be totally unacceptable in an Enterprise environment and is why I prefer Exchange.

Maybe if VMware can improve the support process I will consider presenting it to my customers as another option.

[Lauren]

I can see where Zimbra is well-suited for ISPs, but in the enterprise, it's just harder to administer. With exchange you can just do everything via Active Directory and it takes triple the amount of steps to do that with Zimbra. Maybe things are changing in the newer versions, though.

[Christopher Wells]

@Lauren

With Zimbra you can fully integrate with an external AD for authentication and can import objects from AD for user procurement. Can you specify where your pain points are so that we can discuss and/or help VMware to make improvements?

[Lauren]

Things like specifying groups that are allowed to send email to "all employees" are more difficult to administer. For instance, in Exchange, you just pick the groups that are allowed to. It doesn't seem to be that easy in Zimbra.

[James]

the sad thing is that Outlook is so many light years ahead of Zimbra desktop, so you can't ditch Microsoft completely from your office.

[Roberto]

Don't get me wrong, I think Zimbra is a good platform and will get the features to compete with any other email solution. My sticking point is support, until you actually try getting it, you have no idea how bad it is. In my opinion, they make Exchange really shine in this area. I know I can get help with any Exchange issue that same day, not the case with Zimbra.
Like I said earlier, VMware will clean this up. I talked to VMware about this very issue, they said they were working on it, we'll see...

[Christopher Wells]

@James

I would agree with you that if your users are used to using Outlook that changing to Zimbra desktop as their mail user agent will be a bit of an adjustment. The good thing is that most users already have licenses for Office and thus already have a copy of Outlook. The nice thing is that the functionality that Zimbra provides on the back-end is indistinguishable from Exchange, and I guess that was the main point I was trying to get across in this post. Thanks for your comment!

[Christopher Wells]

@Roberto

I have heard that there are a few issues with Zimbra support and I believe, as you stated, that that is something they are working on improving. It is discussions like this, in a public forum that will hopefully help to affect change within VMware and Zimbra to make the necessary improvements to open up Zimbra to a wider market. Let's give them the benefit of the doubt to see how things improve over the next 12 months. I suspect some changes are coming!

[Christopher Wells]

@Lauren

Thanks for the specifics. That's helpful. I suspect that might be an edge case, but I do see the validity of your request. I suspect that VMware/Zimbra is open to feedback to add that kind of functionality to the Zimbra admin console. Knowing VMware's history with user feedback, if it's something that's possible, it's only a matter of time for it to be implemented. In addition, if you were to manually dig into the Postfix configuration files, you could probably perform that setting, albeit much more manual than with Exchange. So I definitely see your point. I will be more interested to see where they go with the product over the next 12 months. Thanks again for the comment!

[Shane Williford]

Hey Chris...
I've always been curious as to how Zimbra will compare to Exchange. I'm still 'iffy' about giving it serious consideration in my org though. I would like to know about public folder capability since we use those often (public calendars mostly). Any demos you know of for this?

Thanks!

[Christopher Wells]

@Shane

Very interesting question. I am not sure about public folders for calendar sharing actually, but when referring to public folders for document sharing and collaboration, the idea will be to integrate Zimbra with Octopus to enable this functionality. I am not sure how closely the two will be linked, however, I am trying to get my hands on the BETA to get a look at the inner workings of Octopus and how it will integrate. I plan to blog about this as soon as I have something to report, so stay tuned and thanks for your question!

[Svyatoslav Pidgorny]

It's ironic to see Exchange being critiqued for using both old (implying: outdated and obsolete) underlying technology - ESE, and new one (implying: unproven and bug-ridden) - DAGs. Heads, we win, tails, you lose.

And there's one other thing: what is "drop-in" replacement? No-cost migration?

[Christopher Wells]

@Svyatoslav

What I am referring to when speaking about drop-in replacement is the fact that Zimbra has all of the same functionality as Exchange. In other words, it's a collaboration suite, not just another e-mail server.

Thanks for the comment!

[Svyatoslav Pidgorny]

Christopher - thanks for clarification re. drop-in. Full functionality of Exchange would be great achievement. How's Zimbra's UM functionality and is there anything like Outlook Voice Access and speech-to-text capability? From alternative product I've seen so far, only Communicate offered comparable functionality.