How to Troubleshoot the Directory Server System Tuning Analysis Warning and Notice in CentOS

Share this Article :

Before we proceed to install and configure the directory server, we must check for minimum operating requirements. This checking and scanning task can be done by using the linux or unix dsktune command utility. The dsktune utility will help you to scans the system for potential problems, required patches and dependencies and then provide the report of the items found that need to be addressed before running this software in a production environment.

This are the example of my server dsktune report

    [[email protected] ~]# dsktune
    CentOS Directory Server system tuning analysis version 10-AUGUST-2007.
    
    NOTICE : System is i686-unknown-linux2.6.18-194.el5 (1 processor).
    
    WARNING: 590MB 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.
    

1. WARNING:
590MB of physical memory is available on the system. 1024MB is recommended for best performance on large production system.

Also Read :   How to Install and Configure 389 LDAP Directory Server on CentOS 6.4

To address this issue, we have to upgrade the physical memory to at least 1024MB

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

To address this issue, we have to decrease the time default value for tcp_keepalive_time connection. Edit the /etc/sysctl.conf file and add the following lines on line number 6:

    [[email protected] ~]# vi /etc/sysctl.conf
          1 # Kernel sysctl configuration file for Red Hat Linux
          2 #
          3 # For binary values, 0 is disabled, 1 is enabled.  See sysctl(8) and
          4 # sysctl.conf(5) for more details.
          5 #Decrease the time default value for tcp_keepalive_time connection
          6 net.ipv4.tcp_keepalive_time = 300
          7

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

Also Read :   Ldapsearch Examples for 389 Directory

To address this issue, we have to add two parameter at the bottom of limits.conf configuration file as below:

    [[email protected] ~]#  vi /etc/security/limits.conf
         50 # End of file
         51 * soft nofile 524288
         52 * hard nofile 524288
    

Please reboot the server to take effect.


Leave a Reply