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Get PHPwiki up and running with mysql

Ran into some difficulty installing the wiki with mysql backend as the documentation wasn't upto-date.

Below are some notes and customization done during the process:

  1. Download the latest tarball from SourceForge
  2. Extract all files.
  3. Copy 'config/config-dist.ini' to 'config/config.ini' and edit the settings.
  4. Make sure to set the value of 'DEBUG' to either 1 or 0 and do not comment it out. The install process complains if the DEBUG value is not found.
  5. Upload the "passencrypt.php" to the web-server and access it via browser to encrypt password.

Nepali Meta Search Engine : www.metalnepal.com

Quoting the site : ..."metanepal.com is Nepal's first metasearch engine. metanepal uses innovative metasearch technology to search the Internet's top search engines, including Google, msn, kanoodle and nepal specific search engines such as explorenepal.com"

Also by the way they also provide a "News Search" feature. Even though this search engine parses the results of different search engines, it still is a valuable tool for web searchers looking esp. at Nepali sites.

MRTG Performance Monitoring Extensions

MRTG is awesome, but by default it’s limited to SNMP metrics.

The MRTG extension packages allow for the monitoring of performance analysis metrics over SSH or locally, and they’re easy to set up, configure and maintain. With these extensions installed, it's possible to monitor UNIX performance metrics such as CPU and memory utilization, as well as paging, swapping and process statistics. Plus, since you don’t need to have an SNMP daemon running, your system is more secure.

Load test your web application with OpenLoad

OpenLoad is a tool for load testing web applications. It aims to be easy to use and providing near real-time performance measurements of the application under test. This is particulary useful when you are doing optimization as you can see the impact of your changes almost immediately.

OpenSource Tomcat Book

Tomcat is the reference implementation of the Java Server Pages(JSP) and Java Servlet specifications. This means it is the most standards compliant Java server available.

Despite Tomcat's popularity, it suffers from a common shortcoming among open source projects: lack of complete documentation. There is documentation distributed with Tomcat mirrored at jakarta.apache.org. However, there is also an open source effort to write a Tomcat book at tomcatbook.sourceforge.net

Sync hardware clock with current system date and time

There are two main clocks in a Linux system:

The Hardware Clock: This is a clock that runs independently of any control program running in the CPU and even when the machine is powered off.

The System Time: This is the time kept by a clock inside the Linux kernel and driven by a timer interrupt. It has meaning only while Linux is running on the machine.

Often-times, it happens that when you reboot, your clock does not reflect the correct date and time. You may be forgetting to sync the hardware clock with the current system time. Here is how:

First check and set the current system date and time.

# date
# date -s 'Wed May 28 11:35:00 EST 2003'

Then sync your hardware clock with the system time.

# hwclock --show
# hwclock --systohc

man date and hwclock for more info...

speedy NMAP scans

Nmap (http://www.insecure.org/nmap) is the most popular network scanner widely used and misused. Most people tend to ignore the various "switches (options)" and only use the default parameters. It is possible to prioritize SPEED or STEALTH in nmap scans but i'll mainly be talking about maximizing SPEED.

I'll demonstrate this by scanning localhost i.e. my own computer via loopback address. (127.0.0.1) via a non root user :

[d00m@localhost d00m]$ nmap -v 127.0.0.1
 
Starting nmap 3.50 ( http://www.insecure.org/nmap/ ) at 2004-11-21 23:44 EST
Host localhost.localdomain (127.0.0.1) appears to be up ... good.

Partitioning, formating and mounting the Ximeta 120GB External (NDAS) HDD

The NetDisk™ by Ximeta is the first external hard drive that can be connected to either your Local Area Network (LAN) or directly to any PC via USB 2.0. Multiple PCs can simultaneously access any data on the NetDisk™ without sacrificing performance.

If you are connecting it to your network, drivers for some of the popular Linux distros are available on their website. However, it is built against older kernels. Hopefully they will come out supporting the latest kernels.

If you are connecting locally via USB, then it should be picked up as a SCSI hard-drive ( /dev/sda ) automatically.

Using Fedora Core's up2date with Fedora Legacy

The Fedora Core up2date program is, by default, only configured to update from the Red Hat servers. Once your Fedora Core version reaches End of Life, you will want to reconfigure it to use the Fedora Legacy repository so that you can continue to receive updates.

Step 1: Preliminaries: Install up2date

This document assumes you have already installed and are using up2date on your system. If not, it is perhaps better to use yum instead; please see "Keeping Fedora upto date with Yum !" for information on how to install and use yum on your machine. Official documentation can also be reached at: fedoralegacy.org.

How to allow write permissions to mounted partitions...

Open up "/etc/fstab" in your favorite text editor, and add or edit the mounted partition line to be:

/dev/hda1 /mnt/dos1 vfat users,owner,rw,noauto 0 0

Meanings:
/dev/hda1 = hard drive partition
/mnt/dos1 = mount point where you want the disk mounted
vfat = filesystem type
users,owner,rw,noauto = options to mount

users => allow users to mount
owner => allow device owner to mount
rw => read and write permissions
noauto => do not mount at boot (otherwise will mount as root)
0 0 => backup option (to dump, don't dump) and fsck option (don't fsck)

Once you do this, any user can do:

$ mount /mnt/dos1

... and this will mount the filesystem.

Check the man on "fstab" and "mount" for more help.

If you want to get deeper into administration, you could set up an
automounter.

See:
Automount mini-Howto at TLDP.org

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