Installation guide
2.3.2. Red Hat Enterprise Linux System Configuration
After verifying the system's kernel and glibc configuration and installing any required modules and
patches, fine-tune the Red Hat Enterprise Linux system to work with Directory Server. For the best
performance, configure the host server before configuring the Directory Server instance by running the
setup-ds-adm in.pl script.
Section 2.3.2.1, “Perl Prerequisites”
Section 2.3.2.2, “File Descriptors”
Section 2.3.2.3, “DNS Requirements”
2.3.2.1. Perl Prerequisit es
For Red Hat Enterprise Linux systems, use the Perl version that is installed with the operating system in
/usr/bin/perl for both 32-bit and 64-bit versions of Red Hat Directory Server.
2.3.2.2. File Descriptors
Editing the number of file descriptors on the Linux system can help Directory Server access files more
efficiently. Editing the maximum number of file descriptors the kernel can allocate can also improve file
access speeds.
1. First, check the current limit for file descriptors:
cat /proc/sys/fs/file-m ax
2. If the setting is lower than 64000, edit the /etc/sysctl.conf file, and reset the fs.file-max
parameter:
fs.file-max = 64000
3. T hen increase the maximum number of open files on the system by editing the
/etc/security/limits.conf configuration file. Add the following entry:
* - nofile 8192
4. Edit the /etc/pam.d/system -auth, and add this entry:
session required /lib/security/$ISA/pam_limits.so
5. Reboot the Linux machine to apply the changes.
2.3.2.3. DNS Requirements
It is very important that DNS and reverse DNS be working correctly on the host machine, especially if you
are using T LS/SSL or Kerberos with Directory Server.
Configure the DNS resolver and the NIS domain name by the modifying the /etc/resolv.conf,
/etc/nsswitch.conf, and /etc/netconfig files, and set the DNS resolver for name resolution.
Edit the /etc/defaultdom ain file to include the NIS domain name. T his ensures that the fully-
qualified host and domain names used for the Directory Server resolve to a valid IP address and that
that IP address resolves back to the correct hostname.
Reboot the Red Hat Enterprise Linux machine to apply these changes.
Chapter 2. System Requirements
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