2.2. Operating System Requirements

Directory Server is supported on these operating systems: Red Hat Enterprise Linux 4 and 5 (x86 and x86_64), HP-UX 11i (IA 64), and Sun Solaris 9 (sparc 64-bit). The specific operating system requirements and kernel settings, patches, and libraries are listed for each.
Along with meeting the required operating system patches and platforms, system settings, like the number of file descriptors and TCP information, should be reconfigured to optimize the Directory Server performance.
Directory Server includes a tool, dsktune, which simplifies configuring your system settings. This section describes what settings to change on the machine on which Directory Server is installed.

2.2.1. Using dsktune

After the packages for Directory Server are installed there is tool called dsktune which can scan a system to check for required and installed patches, memory, system configuration, and other settings required by Directory Server. The dsktune utility even returns information required for tuning the host server's kernel parameters.

NOTE

The setup program also runs dsktune, reports the findings, and asks you if you want to continue with the setup procedure every time a Directory Server instance is configured.
Red Hat recommends running dsktune before beginning to set up the Directory Server instances so that you can properly configure your kernel settings and install any missing patches. On Red Hat Enterprise Linux and Solaris, the dsktune utility is in the /usr/bin directory; on HP-UX, it is in /opt/dirsrv/bin. To run it, simply use the appropriate command:
/usr/bin/dsktune

Red Hat Directory Server system tuning analysis version 10-AUGUST-2007.

NOTICE : System is i686-unknown-linux2.6.9-34.EL (1 processor).

WARNING: 1011MB of physical memory is available on the system. 
1024MB is recommended for best performance on large production system.

NOTICE : The net.ipv4.tcp_keepalive_time is set to 7200000 milliseconds
(120 minutes).  This may cause temporary server congestion from lost
client connections.

WARNING: There are only 1024 file descriptors (hard limit) available, which
limit the number of simultaneous connections.

WARNING: There are only 1024 file descriptors (soft limit) available, which
limit the number of simultaneous connections.

NOTE

dsktune is run every time the Directory Server configuration script, setup-ds-admin, is run.