Server Admin is the full-featured administration tool now included with the OS X server; it includes a few new options that are in line with the added services provided in OS X Server 10.5. Most notably, there is true tiered and distributed administration capability, which allows a super administrator to distribute rights to servers, services and users -- not just services and users as was the case in prior releases.
Other features that Leopard Server users will appreciate are a dashboard widget for monitoring the server at a glance and an adaptive firewall. That second one is a big deal. Firewall rules are notoriously complex for most administrators, and responding to attacks while still providing service can be quite a resource drain. The adaptive firewall will activate the ports required for services that are active on the server. It will also do things like monitor authentication challenges and SSH attempts. If a threshold is reached, the firewall will automatically put a rule-blocking service on that port. After a set period, it will remove that rule and check for continued offending behavior. Furthermore, it will make log entries and alert an administrator.
This is a boon to anyone without extensive security resources -- in other words, most of us -- and is helpful to anyone who is not monitoring his network interface cards at some point in a 24-hour period (again -- most of us).
Finally on the administration front is the most important administrative tool on any server: the backup system. Leopard Server will incorporate Apple's Time Machine software as its backup system, enabling an administrator to easily configure, backup and restore files. Moreover, it will include a backup feature so that after a catastrophic failure involving the operating system drive, a backup can be restored to the desired point in time during the operating system build process -- not as a postbuild action. That makes restoration a less complex and time-consuming process, something any admin who is sweating his way through restoring a crashed system will appreciate.
New services, odds and ends