Basic iptables howto

Iptables is a firewall, installed by default on all official Ubuntu distributions (Ubuntu, Kubuntu, Xubuntu). When you install Ubuntu, iptables is there, but it allows all traffic by default. Ubuntu 8.04 Comes with ufw - a program for managing the iptables firewall easily. There is a wealth of information available about iptables, but much of it is fairly complex, and if you want to do a few basic things, this How To is for you. Basic Commands Typing sudo iptables -Llists your current rules in iptables. If you have just set up your server, ...

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Routing for multiple uplinks/providers

A common configuration is the following, in which there are two providers that connect a local network (or even a single machine) to the big Internet. ________ +------------+ / | | | +-------------+ Provider 1 +------- __ | | | / ___/ \_ +------+-------+ +------------+ | _/ ...

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Cum poti accesa de la distanta computerul tau - Chrome Remote Desktop - Teamviewer

Daca doriti sa accesati de la distanta computerul dvs. puteti folosi Google Chrome Remote Desktop. De la inceput se anunta ca un adversar de temut al lui Temaviewer. Google Chrome Remote Desktop permite sa accesati de la distanta computerul  dvs. sau un alt calculator  prin instalarea unei extensii pentru browserul dvs. Google Chrome. Pentru cei familiarizati cu Remote Assistance ,Google Chrome Remote Desktop a introdus o sectiune dedicata care permite sa acordati suport tehnic prin facilitatea user-to-user screen sharing. Pentru ...

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Running Additional Programs at Boot Time in CentOS

The /etc/rc.d/rc.local script is executed by the init command at boot time or when changing runlevels. Adding commands to the bottom of this script is an easy way to perform necessary tasks like starting special services or initialize devices without writing complex initialization scripts in the/etc/rc.d/init.d/ directory and creating symbolic links. The /etc/rc.serial script is used if serial ports must be setup at boot time. This script runs setserialcommands to configure the system's serial ports. Refer to the setserial man page for more information. ...

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Centos iptables FORWARD and NAT Rules

Most organizations are allotted a limited number of publicly routable IP addresses from their ISP. Due to this limited allowance, administrators must find creative ways to share access to Internet services without giving limited public IP addresses to every node on the LAN. Using private IP address is the common way to allow all nodes on a LAN to properly access internal and external network services. Edge routers (such as firewalls) can receive incoming transmissions from the Internet and route the packets to the intended LAN node. At the same ...

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How to enable IP Forwarding

By default any modern Linux distributions will have IP Forwarding disabled. This is normally a good idea, as most peoples will not need IP Forwarding, but if we are setting up a Linux router/gateway or maybe a VPN server (pptp or ipsec) or just a plain dial-in server then we will need to enable forwarding. This can be done in several ways that I will present bellow. Check if IP Forwarding is enabled We have to query the sysctl kernel value net.ipv4.ip_forward to see if forwarding is enabled or not: Using sysctl: sysctl net.ipv4.ip_forward ...

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How To Add Static Routes In CentOS

There are numerous ways to add static routes in Linux (CentOS). The easiest way is via the terminal by using one of the following examples. How to add a static route for a specific host in Linux. route add -host 192.168.1.47 gw 192.168.10.1 route del -host 192.168.1.47 gw 192.168.10.1 How to add a static route for a specific network in Linux. route add -net 192.168.1.0/24 gw 192.168.10.1 route del -net 192.168.1.0/24 gw 192.168.10.1 How to add a default gateway. route add default gw 192.168.10.1 route del default gw 192.168.10.1 ...

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Cum dai access la internet la alt calculator din casa sau Cum configurezi Windows 7 pentru Internet Connection Sharing

Daca vrei sa dai access la un alt calculator din casa prin calculatorul tau poti folosi  Internet Connection Sharing .Dureaza 2 minute pana configurezi. Trebuie sa ai doua placi de retea pe calculatorul tau(una care se va conecta la providerul de internet si cealalta pe computerul care il vreti conectat la internet). Aveti nevoie de un cablu crossover pentru a interconecta cele doua calculatoare. Cum configurezi  Internet Conection Sharing ? 1. Right-click pe icoana Network Configuration din System Tray. 2. Click Open Network ...

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How to properly issue a certificate for Forefront TMG Standalone Arrays in a workgroup

Hello, Due to the problems and pain we have encountered in making Forefront TMG 2010 Standalone Array in a workgroup to work on VMware ESX 3.5 Update 5 I will detail the steps for creating and importing certificates to TMG certificates store and point out to the problems with TMG Control service dependencies. This is the environment we had: · Two Forefront TMG 2010 Enterprise Servers in a workgroup configured in Standalone Array with one TMG configured as Array Manager and another configured as Array Member · Windows Server 2008 R2 Standard ...

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0×80094801 – the request contains no certificate template information

On my Windows 2008 (AD) Certificate services console I get this error message when I try to add a Web Server Certificate Request file. 0×80094801 – the request contains no certificate template information The solution is to import the Certificate Request in command line with CertReq tool.  Use the following command to import your Certificate Request file. certreq -submit -attrib "CertificateTemplate:WebServer" <Cert Request.req> If the template is different, find the correct template name in “Certificate Authority” console. If ...

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