A new feature in the latest update to OS X Server is a caching server. This is designed to cache files in setups with multiple users so files only need to be downloaded once from the internet (or from the Mac App Store, iTunes Store, etc.). Files are cached locally, so users can save time getting downloads.
Apple has published a technical note explaining how to configure the caching server. You can set a limit to the amount of disk space used for the cache, you can choose a location for the cache, set the number of concurrent clients accessing it and much more.
This looks like a valuable feature for any organization running OS X Server.
Apple has published a technical document explaining how to set message size limits for the mail server in OS X Server. By default, messages are limited to 10 MB, but you can change this from the command line using the serveradmin command:
sudo serveradmin settings mail:postfix:message_size_limit = number
See Apple's technical document for more information, and how to specify the number in the command above.
Apple recently published a technical note explaining how to enable the adaptive firewall in OS X Server. This is a type of firewall that automatically creates temporary rules according to certain events. For example, a number of failed login attempts will cause the adaptive firewall to create a temporary rule to block the IP address attempting to log in.
To do this, run the following commands as an administrative user:
If you use Lion Server, and its wiki server, you may find it useful to use custom URL protocols for internal documents and links. Apple has published a technical note explaining how to do this. This document explains how to create the necessary configuration file - /etc/collabd/filter_whitelist.plist - for any custom URL protocol you wish to use.
I have had nothing but trouble with SMB (Windows Sharing) services in Mac OS X Server 10.7. These problems were supposedly solved in 10.7.3, but my particular issues seem to still be there in several cases (Windows XP name browsing not working, Guest access not working, performance issues, dropped connections), and may be related to the Windows XP (versus Windows Vista/7) clients I'm dealing with. All of these were working fine with Mac OS X Server 10.5.8 when a string of hardware failures required replacement with the current version, which is working well for the Mac OS X clients.
I have found that replacing the Apple supplied services with the open source Samba version (dropped by Apple in Mac OS X Lion for apparent licensing issues) has solved these problems, and provided faster performance. Unfortunately setup isn't well documented, takes a while, and has no GUI tool (SharePoints I miss you!).
In hopes that I can give someone a head start for doing this if they need to, I've cobbled together a recipe from various sources. There are likely some flaws, and it is probably missing some details and options. Please feel free to add or update in the comments.
If you plan to update your OS X Server to 10.7.2 be sure to restart your machine and stop all server services, especially iCal Server and Address book server before applying the update.
It happened to me yesterday that I applied the OS X 10.7.2 update to my Mac mini server without closing any apps. I just ran it. After the update it turned out, this was a big mistake. All calendar entries of the past three weeks and many contacts were lost.
I was not able to recover anything from time machine. Lion server keeps the CalDAV and CardDAV data in a PostgreSQL database which is apparently not backed up by TimeMachine. Also, the PostgreSQL uses transactions which need to be 'closed' before they end up being permanently written into the DB tables.
What I found from reviewing the postgres log file (/Library/Logs/PostgreSQL.log) is that the 10.7.2 server update will apply a whole bunch of database structure updates to PostgreSQL but without committing the latest transaction. Given that CalDAV entries a quite small, the transaction log may contain a lot of data which is then lost.
So, be aware to make sure you have your transaction log committed before you run the update. I assume a proper server shutdown (or reboot) and stopping of the server processes will do just this. Afterwards it should be safe to update.
Alternatively (and this is my weekend-fun-duty) have a client with all up to date calendars off-line and aside which servers as a backup.
[crarko adds: I haven't tested this one. In fact, I haven't had the chance to try Lion Server at all yet. I'd be interested to hear if others have experienced issues like the one described here.]
I ran into a problem recently where I was unable to boot into any of the images I had made from any Mac. I have NetRestore and one NetBoot image, but not one of my Macs could get to it. After many failed attempts, I finally tricked it into letting me boot. Here's how.
The problem actually has to do with the way that NetBoot filters computers. It used to be that you could turn filtering on and off, but now, it is not so simple. In the Image Properties window, you have the option to either all model types, or just the ones selected from a given list.
However, MAC filtering is different, you can't simply say allow all. The default selection is to allow only only those computers with the matching MAC addresses in the list below and deny others. This is what is preventing computers from being able to boot. And unless you are interested in manually entering in every new MAC address, it is impractical.
The second option is to deny only those computers in the list below and allow all others. It would be easy to select the second option, however, Lion Server has a bug that prevents you from selecting Deny Only if the list is empty. If you simply select it and save, it reverts to the default allow only option.
To get around this bug, enter in a MAC address of 00:00:00:00:00:00 and then select the Deny Only option. Save the changes and now all of your computers should be able to boot to any images you have.
Note: you'll have to make this change for every image.