Kernel tuning on a production server shouldn’t be taken lightly, because the wrong parameters could cause your system to fail to boot, software to malfunction, or hardware peripherals to become unavailable. Always practice on a test system and keep a backup copy of your old kernel. Whenever possible, hire a consultant with kernel experience to help, and use this chapter and other references as a guide to prepare you for what to expect.
We will use an example based approach to examine the various iptables commands. In this first example, we will create a very simple set of rules to set up a Stateful Packet Inspection (SPI) firewall that will allow all outgoing connections but block all unwanted incoming connections:
Â xinetd, the eXtended InterNET Daemon, is an open-source daemon which runs on many Linux and Unix systems and manages Internet-based connectivity. It offers a more secure extension to or version of inetd, the Internet daemon. xinetd performs the same function as inetd: it starts programs that provide Internet services. Instead of having such servers started [...]
Each instance of SQL Server consists of a distinct set of services that have specific settings for collations and other options The directory structure, registry structure, and service names all reflect the instance name and a specific instance ID created during SQL Server Setup. An instance is either the default instance or a named instance. [...]
It includes an attractive web interface for users, admins, and clients to access and update their DNS zone data as well as a rich API for provisioning systems to interact with. All zone data is stored in MySQL and is extracted by export scripts to the DNS server of choice (tinydns, BIND, PowerDNS). Updates are [...]
GRUB is one of the more common boot loaders in use on GNU/Linux systems today. I have GRUB installed on both my boxen, on one to facilitate dual-booting between Windows XP Home (for Kelly, not for me) and on the other to facilitate booting between kernels. GRUB is controlled by a file called menu.lst which [...]
If you are looking for a way to speed up your PHP pages on Apache, this is the software you want to install. Huge performance gains can be had when using this software to precompile and cache your PHP pages, and it is very simple to install.
Websense Express installs with Windows NT Directory as its default directory service. If your network uses Active Directory, you cannot assign policies to users until you reconfigure the directory service settings in Websense Manager. Filtering can occur with the wrong directory service selected, but user data is logged incorrectly. In addition, user-based policies cannot be [...]
Subversion depends on a number of third party tools and libraries.Some of them are only required to run a Subversion server; others are necessary just for a Subversion client. This section explains what other tools and libraries will be required so that Subversion can be built with the set of features you want
Let say you are on an expensive satellite link that can barely provide enough bandwidth for your company’s Internet Access and you will want to do whatever you can to get as much as possible out of this link. Moreover, occassionally you loose power from the utility company, long enough for your UPS to run [...]
Red Hat Linux provides a utility calledÂ diskcheckÂ that monitors the amount of free disk space on the system. Based on the configuration file, it will send email to the system administrator when one or more disk drives reach a specified capacity. To use this utility, you must have theÂ diskcheckÂ RPM package installed. This utility is run as [...]