Quality Open Source Calendaring / Scheduling?

Jim R. Wilson writes "In past jobs, I've used Microsoft Outlook/Exchange, Novell Groupwise, and Google Calendar for handling business appointments. I'm sorry to say it, but I have yet to see a rival to Microsoft's scheduling features. On Slashdot I have occasionally read rumblings that there are better open source email and calendaring solutions out there. Can anyone substantiate this claim? What are the OSS alternatives? Can any compete with Microsoft's resource scheduling?"

no

[Anonymous Coward]

no

Haven't found much

[cbreaker]

I haven't found much, either. It's either some half-done web-based solution or it's got seriously missing features.

Evolution works great with Exchange; all they need now is to create their own back-end =)

PS. Public folders have gone away in Exchange 2007; big mistake if you ask me. It was a selling point for Exchange.

Citadel is the best i know of:

[guysmilee]

Citadel is the best i know of: http://www.citadel.org/doku.php [citadel.org]

Could you help us help you?

[narrowhouse]

Jim,

I hate to say this, but unless you give us a few reasons why some of the solutions you have looked at are not sufficient I doubt you will get any meaningful response.It's a pretty common problem when people ask for an open source replacement for a program they have used and were reasonably happy with.

Without some starting point for comparison you will just get dozens of stories about how product X works fine for them.

Kontact

[padonak]

Try Kontact [kde.org] (part of KDE Personal Information Manager).

Re:.....or

[disasm]

opengroupware has a plugin for working with outlook. I haven't used that one in a while though.

Sam

CalDav

[jlittle]

CalDav is the wave of the future, with most calendaring clients supporting it (but not MS), and many servers commercial and otherwise also supporting it (Zimbra). The real coming out party was the commercial release of both OSX Server 10.5 and the client, which have both ends. But guess what, the server is open source: calendar server [macosforge.org] can be gotten and put on any platform. If you want something today, Zimbra or OSX Server are there for the taking. RedHat has a Messenging product coming out based on Zimbra for this exact purpose.

What about Darwin Calendar Server?

[SuperKendall]

Apple provides a nice calendar server [ittoolbox.com] with Leopard server - but it works with Linux (any anything else running Python) as well...

Not really

[initdeep]

Zimbra http://www.zimbra.com/ [zimbra.com]

Scalix http://www.scalix.com/ [scalix.com]

are the two closest, but honestly, neither is a perfect replacement.

No callenders?

[tristian_was_here]

Mozilla has an active callender project with Sunbird and Lightening

http://www.mozilla.org/projects/calendar/ [mozilla.org]

Re:.....or

[Anonymous Coward]

Scalix

Re:Haven't found much

[Anonymous Coward]

Sure about public folders?

http://www.microsoft.com/exchange/evaluation/topquestions.mspx?wt.svl=overview [microsoft.com]

Q. What is happening with Public Folders?
A.

Public Folders are included and supported in Exchange Server 2007. Microsoft has communicated that future releases of Exchange Server may not include public folders. If you use Public Folders, read the Exchange Team Blog on the topic of public folders for more guidance.

Re:What features?

[jimbojw]

In other words, what features do you use in MS products that you haven't found in the free/open source applications?

Sorry I wasn't clear enough in my initial question. What really impresses me about Outlook/Exchange is when you go to schedule a meeting, it allows you to see when all the participants, rooms and resources (like projectors) are available in a horizontal chart of sorts. People who are busy are marked off in blue, out of office is purple, etc. To find a time that works for everyone, you just scan across until you see a vertical bar of white (everyone free), or try to minimize conflicts.

I don't know of MS holds a patent on the UI, but I haven't seen it anywhere else. Also, with respect to calendaring, in Outlook you can open up several calendars (yours and others) side-by-side in order to see who's free when. It's a pretty simple bit of eye candy, but nonetheless, I've only seen it in Outlook.

Re:Haven't found much

[ibi]

It's worth looking at Chandler (fat client) and Cosmo (server) from

http://www.osafoundation.org/ [osafoundation.org]

It's been a long time coming, but it's finally approaching a useable release and it's quite interesting. I think it will be a real choice in 2008...

iCal Server

[HiredMan]

Apple's iCal Server is Open Source PHP (with Twisted Framework) and based on the new CalDAV open standard. Everyone (with the possible exception of Microsoft) is moving to CalDAV as the open standard. Many big companies (Oracle, IBM, Google) are involved with the committee and hopefully the holy grail of inter-operable calendaring systems - including free/busy, invitations etc - is finally on the horizon.

The server just officially went gold with Leopard but has actually been done for a while now. Apple's iCal Server and (closed source) Client are currently the most polished products but now that there is a solid CalDAV server I expect that the various clients with gain alot of polish and other CalDAV servers should start to roll out as well.

Check out the CALCONNECT standards body for more information: http://www.calconnect.org/ [calconnect.org]

=tkk

PS Microsoft is finally a member but their commitment level is not that of the other partners.

Re:iCal Server

[Erskin]

Apple's iCal Server is Open Source Python (with Twisted Framework) and based on the new CalDAV open standard.

(It's probably an innocent slip of the brain, but figured I'd mention it for anybody unfamiliar with the tech so they don't get confused.)

Re:Haven't found much

[sharkey]

Public folders have gone away in Exchange 2007

They are in there, just disabled by default. If you use Outlook 2003 or older they are required, so Exchange 2007 includes them.

Re:What features?

[99BottlesOfBeerInMyF]

I don't know of MS holds a patent on the UI, but I haven't seen it anywhere else.

This function is available with the CalDav server standard and that particular feature is available in the implementations in the open source Zimbra client/server and the 10.5 version Apple's iCal server/client. I don't know about other implementations, but I imagine most other ones either include this or will soon, as Caldav has really taken of in adoption by major projects. Zimbra even offers that feature via the Web interface to their server.

Also, with respect to calendaring, in Outlook you can open up several calendars (yours and others) side-by-side in order to see who's free when.

I think Evolution has an interface like this (works with CalDav), but if I recall Zimbra allows you to overlap as many calendars as you want in one window, making the comparison quite a bit easier IMHO.

I'd definitely look at Zimbra if you're serious about a OSS solution with lots of features and compatibility with both standards and proprietary interfaces (they have a full featured Exchange plug-in so users can still use Exchange as their client if they want). The server will run on all the popular Linux distros, OS X, and as a VMWare appliance.

Re:Haven't found much

[samkass]

The best candidate I've seen for the full calendaring "infrastructure" is the open CalDAV [wikipedia.org] spec, but it's only really used commercially by Apple at this point. But since Apple has released their reference implementation as open source [wikipedia.org], perhaps we'll get more implementations and a snowball effect of support.

Re:Zimbra

[myowntrueself]

Zimbra is, arguably, not Open Source.

It comes under an 'attribution license' and hence cannot be forked. Its 'badgeware'.

Ie: you cannot take the source code of Zimbra and produce your own version *without* the Zimbra logos.

Re:iCal Server

[MouseR]

It should be noted that

- Apple's Calendar Server is indeed open source [royhooper.ca], unlike mentioned above.
- Apple's current implementation of recurring events in their CalDav server has some issues.

Disclaimer:
It should also be noted that I work for Oracle in the very same division responsible for the calendaring stuff and that my intent is not to diminish Apple's offering. Oracle aims for full interoperability with other CalDAV-compliant offerings, including that of Apple.

Re:.....or

[ahodgson]

I'm sure if Microsoft ever allows outside software to properly interoperate with Exchange, that will happen. But they don't.

Shocking, I know.

But of course... Citadel..

[wizard of aahz]

So you want something that's truly open source? You don't want to have to pay for the commercial version. You want something that's not new on the block and looking for funding. How about a software package where the leadership is devoted to the open source mindset, beliefs and methodologies?

Software that actually works. It's in use. It's actively being maintained. As new technology is released, there's a proven track record of it being incorporated into the software.

Then you're really making a mistake if you don't look at citadel.

Email, Calendaring, Contacts, multiple interfaces, multiple standards compliant protocols, instant messaging and it all can run on one server. But wait.. It scales! So if you want to run multiple servers and have them communicate, go ahead. It's built right in.

Visit http://citadel.org/ [citadel.org] for more information and to download or there's even a vmware appliance, all set up and ready to go. All you need to do is download and run. Try http://www.vmware.com/appliances/directory/723 [vmware.com]. -

Sun's JES is worth evaluating

[Arrogant-Bastard]

It makes my short list, along with ZImbra, Scalix, and Openchange (so far).

The nice things about JES are (a) it's rock-solid (b) it works well with many mail clients, even horribly broken ones like Outlook (c) while it doesn't have every possible calendar feature in the world, it has all of the ones that people actually use (d) it scales amazingly well -- it's really no problem to get it to support millions of users (e) because it's been around for a while (including a prior incarnation as a Netscape product) there's a pretty solid support community for it (in addition to Sun) (f) it's flexible enough to support integration with other products.

The bad things about JES are (a) the install is complicated, even if you're very accustomed to complex installs (b) the documentation, like much of Sun's documentation, is poorly written, verbose, uses opaque terminology, and lacks cohesion (c) the log files are inscrutable (d) it's somewhat bloated (somebody needs to trim all the legacy code out of it) (e) it's overkill for anyone who just needs a mail server (i.e., no calendaring).

But...given that you get mail, calendaring, LDAP, all rolled up in one package -- it's at least worth looking at. I'm aware of any number of places that have migrated from Exchange to JES, so at least their requirements were met.

Re:Citadel is *the* solution

[IGnatius T Foobar]

I've looked at Citadel myself. I think it looks good, but I also think that when you say "shared calendars" to most middle and upper management, it gets interpreted as "Outlook + Exchange".

Sadly, there is quite a bit of truth to that statement. Fortunately, there is an Outlook connector for Citadel currently in beta test. It's quite nice -- while most non-Microsoft Outlook connectors merely do synchronization, this one implements a full store (i.e. the equivalent of what you get when you connect to Exchange). Outlook and non-Outlook clients will *both* be first class citizens on a Citadel system. We'll have this out within the next couple of months, and it'll be very useful.

Re:Haven't found much

[maetenloch]

In other news, NASA spends 1 million on a pen that writes in space. Because, you know, pencils are so lower class.

It would be funny if it were true, but it's not according to Snopes. Space Pen [snopes.com]

Zimbra!

[alexborges]

Zimbra does it, does it very well and can be made compatible with full fledged outlook.

You dweebs cant even do a google search before just saying "no", can you?

Re:Haven't found much

[greginnj]

Pencils are dangerous in space.

1. They are more pointed than pens, and thus more likely to puncture things that shouldn't be punctured.

2. They create dust, which is a no-no on space missions. Wood pencils (obviously) from sharpening. Mechanical pencils are prone to have their leads break off, and float about. More to the point, the operating mechanism of both kinds of pencil is to rub off graphite dust onto paper. Some of this dust may be released by smudging.

Remember that graphite, and thus graphite dust, is conductive. Do you want to take the risk of conductive graphite dust causing a component to short out?

Why do you want NASA missions to fail???? ( oblig bit o funny )

Re:Zimbra!

[stacey7165]

Zimbra is a great alternative to Exchange. I have also used Doodle http://www.doodle.ch/main.html [doodle.ch] to schedule/suggest meeting times that work for people through a poll mechanism, however it doesn't integrate to your calendar to remind you that you have the meeting...

...shameless plug: if you're looking for open source monitoring software either your Exchange or Zimbra installation, you should check out Hyperic. Its open source and manages both of them right out of the box. :)
Stacey Schneider
http://www.hyperic.com/ [hyperic.com]

Re:no

[jdparkinson]

Jim, take a look at Thunderbrid with Lighting or Sunbird. http://www.mozilla.org/projects/calendar/lightning/ [mozilla.org] The community is making great progress. It may not be everything you want but I think you will find it to be pretty good and getting better all the time. Your input will also help make it better.

Re:Citadel is *the* solution

[WebCowboy]

I expect that MS-Exchange connectivity will be licensed under GPLv3, just as the rest of the citadel and webcit projects are presently licensed.


Sadly it looks like the connector is being developed by a closed source developer rather than within the Citadel project itself so my prediction isn't quite true. Still it would make a great alternative to Exchange, and fortunately for me Exchange compatibility is not an issue.

I quite enthusiastically plug Citadel wherever I can, not only because it performs extremely well and is easy to administer, but because the project is very open (the citadel.org site has a LOT of info on protocols and other technical developer stuff) and the more people that are aware of it the more likely people will get involved in developing it and moving it forward (eventually, perhaps, leading to a Free exchange connector ;-). I'm still amazed that software of this quality, with a 20 year history of development, continues to fly under the radar with much of the Free software community.

Re:Power Failure Resistant:

[Anonymous Coward]

Pencil has persistence and data corruption issues.

Re:Zimbra!

[lazybeam]

I used to work at a church where the previous IT guy had setup a standard Fedora box as a server. Everyone used Outlook with POP3 mail over the LAN. It was only a Celeron 600 that also did file serving, spam/virus scanning and web filtering. With 35 users it was seriously underpowered.

I upgraded them to two servers: RHEL with Zimbra for everything mail-related and CentOS for fileserving. They were even considering Evolution for the client, which I found funny for a church! Anyway, they've been like this for over a year and there has been no major problems. The new servers even had Gigabit cards so people could get full speed from the gigabit switch!

They were a little against Exchange because their neighbouring retirement village used Exchange on SBS and had no end to problems. Last I heard they linked networks and migrated the retirement village accounts to their Zimbra server.