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IP Masquerade is a networking function in Linux similar to the one-to-many (1:Many) NAT (Network Address Translation) servers found in many commercial firewalls and network routers. For example, if a Linux host is connected to the Internet via PPP, Ethernet, etc., the IP Masquerade feature allows other "internal" computers connected to this Linux box (via PPP, Ethernet, etc.) to also reach the Internet as well. Linux IP Masquerading allows for this functionality even though these internal machines don't have an officially assigned IP address . MASQ allows a set of machines to invisibly access the Internet via the MASQ gateway. To other machines on the Internet, the outgoing traffic will appear to be from the IP MASQ Linux server itself. In addition to the added functionality, IP Masquerade provides the foundation to create a HEAVILY secured networking environment. With a well built firewall, breaking the security of a well configured masquerading sys...

this is tutorial to install nvidia display driver on enterprise linux *all of the command must be executed as root user  1. check the nvidia product type lspci -nn | grep VGA here you will have the infomation what proprietary driver you should download from www.nvidia.com site. 2. install the Development Tools group packages, kernel headers, kernel devel, and dkms yum groupinstall "Development Tools" yum install dkms kerne-devel kernel-headers 3. disable the nouveau driver using your text editor vim /etc/modprobe.d/blacklist.conf #add this line blacklist nouveau 4. go to /boot directory make a copy of initramfs file cd /boot mv initramfs-$(uname -r).img initramfs-$(uname -r).img.bak 5. proceed to create new initramfs file dracut -v initramfs-$(uname -r).img $(uname -r) 6. change inittab to start the system with no X11 vim /etc/inittab change runlevel to 3 7. restart the system reboot 8. login in command line as root, run the script to install t...

in our tour of duty, we are facing another case where the ethernet device on motherboard didn't recognize by linux kernel. here are the specification : motherboard  : GIGABYTE G41MT-S2PT linux operating system :   Scientific Linux 6.0 another enterprise-based linux (centos, oracle linux) will works (i hope). we have try with fedora 14 , but it didn't recognize the device and the driver is not available yet. fortunate we have found the driver in binary (RPM package). first download the package file from the following links : i386 driver : kmod-atl1e-1.0.1.14-1.el6.elrepo.i686.rpm x86_64 driver : kmod-atl1e-1.0.1.14-1.el6.elrepo.x86_64.rpm step 1 install the package by typing  (as root) rpm -ivh kmod-atl1e... .rpm step 2 change directory to /etc/sysconfig/, please check whether there is a file called network, if there isn't create new file with your favourite text editor. cd /etc/sysconfig/ vim network the content of network file : NETWORKING=...

systemd does not use /etc/inittab file to change the default runlevel. systemd uses symlinks to point to the default runlevel. You have to delete the existing symlink first before creating a new one. # rm /etc/systemd/system/default.target example to switch to runlevel 3 : # ln -sf /lib/systemd/system/multi-user.target /etc/systemd/system/default.target next example if you want to switch to run level 5 : # ln -sf /lib/systemd/system/graphical.target /etc/systemd/system/default.target another options that may apply : poweroff.target --> runlevel 0 rescue.target    --> runlevel 1 multi.user.target --> runlevel 2,3,4 graphical.target --> runlevel 5 reboot.target --> runlevel 6 source: http://fedoraproject.org/wiki/Systemd

basic usage to access the remote server $ rdesktop (serveraddr) example to access the computer on 192.168.1.1 $ rdesktop 192.168.1.1 to enable full screen mode $ rdesktop -f 192.168.1.1 to set spesific windows size $ rdesktop -g 800x600 192.168.1.1 (some common screen resolution can be use: 800x600, 1024x768, 1280x1024) sharing files to share a local directory with windows os remote server $ rdesktop -r disk:(sharename)=(path) (serveraddr) example to access the remote server on 192.168.1.1 and the sharing directory /home/vadya/pub/ using network share name "sharing" $ rdesktop -r disk:sharing=/home/vadya/pub 192.168.1.1 optimizing speed enabling compression (-z) and disabling mouse events (-m) will reduce network bandwidth and can make the connection much more responsive.  $ rdesktop -z -m 192.168.1.1 using a smaller color palette helps reduce network bandwidth $ rdesktop -a 16 192.168.1.1 source: http://wiki.rrc.uic.edu/wiki/RRC-SCS:_Using_rd...

Openfire is a powerful instant messaging (IM) and chat server that implements the XMPP protocol. This document will guide you through installing Openfire. For a full list of features and more information, please visit the Openfire website: http://www.igniterealtime.org/projects/openfire/ A. INSTALLATIONS first download the binary package from : http://www.igniterealtime.org/openfire-3.8.1-1.i386.rpm then r un it using your package manager to install Openfire to /opt/openfire (as root): rpm -ivh openfire_3_0_0.rpm Note: if you are using the .tar.gz build, it does not contain a bundled Java runtime (JRE). Therefore, you must have JDK or JRE 1.5.0 (Java 5) or later installed on your system. You can check your java version by typing "java -version" at the command line and (if necessary) upgrade your Java installation by visiting http://java.sun.com. B. SETUP the database In the Openfire setup tool, use the following values: driver: com.mysql.jdbc...

here are examples of the systemctl version of a few common chkconfig and service commands. 1. to list processes # chkconfig --list # systemctl list-units 2. to enable a service # chkconfig (servicename) on # systemctl enable (servicename).service 3. to disable a service # chkconfig (servicename) off # systemctl disable(servicename).service 4. to start a service # service (servicename) start # systemctl start (servicename).service 5. to stop a service # service (servicename) stop # systemctl stop (servicename).service 6. to see the status of a service # service (servicename) status # systemctl status (servicename).service or # systemctl is-active (servicename).service source: http://fedoraproject.org/wiki/SysVinit_to_Systemd_Cheatsheet