Getting Started

• If you are just getting started with configuring your firewall.
• Most of the rules that are described here assume that your iptables is set to drop incoming traffic, through the default input policy, and you want to selectively allow traffic in.
• Use whichever subsequent sections are applicable to what you are trying to achieve. Most sections are not predicated on any other, so you can use the examples below independently.
• Use the Contents menu on the right side of this page (at wide page widths) or your browser’s find function to locate the sections you need.
• Copy and paste the command-line examples given, substituting the values in red with your own values.

Keep in mind that the order of your rules matter. All of these iptables commands use the -A option to append the new rule to the end of a chain. If you want to put it somewhere else in the chain, you can use the -I option which allows you to specify the position of the new rule (or simply place it at the beginning of the chain by not specifying a rule number).

Allow Loopback Connections

The loopback interface, also referred to as lo, is what a computer uses to for network connections to itself. For example, if you run ping localhost or ping 127.0.0.1, your server will ping itself using the loopback. The loopback interface is also used if you configure your application server to connect to a database server with a “localhost” address. As such, you will want to be sure that your firewall is allowing these connections.

Nam eu est ac metus posuere rutrum. Curabitur elementum ac velit nec scelerisque. Proin turpis purus, maximus a dolor ac, rhoncus sagittis nisi. Sed sapien lacus, elementum sit amet nisl et, bibendum volutpat eros. Aliquam tempor eros mattis felis cursus ultricies. Vivamus quis hendrerit purus, vel gravida diam. Quisque placerat posuere tortor bibendum pretium. Ut tincidunt, ipsum non pretium pellentesque, nunc nisl auctor nibh, ac molestie est ipsum a urna. Cras ac erat a urna pretium vulputate at ut sem. In velit enim, hendrerit sed sapien id, sodales luctus nisl. Nunc sagittis non augue at vestibulum. Vestibulum sit amet pretium felis, sed varius justo. Nam at mi est. Cras eu consequat dolor. Phasellus non vestibulum nibh, vitae scelerisque tortor.

Basic Configuration

Integer at lectus augue. Ut feugiat odio felis. Nullam aliquet diam vel elit tempus aliquet. Phasellus mattis nec neque eu porta. Sed purus risus, tincidunt a mauris nec, placerat dapibus ipsum. Suspendisse facilisis convallis orci nec tincidunt. Nam posuere quis ipsum in tempus.

Duis volutpat a massa eu egestas. Duis ac lectus sollicitudin, bibendum augue sit amet, sollicitudin augue. Maecenas accumsan egestas dolor, non cursus massa imperdiet et. Praesent euismod nec dolor sit amet condimentum. Fusce vulputate sed enim sed egestas. Donec porta risus vulputate, sodales massa vitae, tempor purus. Aenean mattis bibendum elit, sit amet consequat dolor vitae.

Conclusion

That should cover many of the commands that are commonly used when configuring a firewall. Of course, iptables is a very flexible tool so feel free to mix and match the commands with different options to match your specific needs if they aren’t covered. Continue reading this guide at Digital Ocean. This article has been used as an example of an Ecko WordPress theme. This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

The post Essentials: Common Firewall Rules and Commands appeared first on EckoThemes.

I don’t believe you have to be better than everybody else. I believe you have to be better than you ever thought you could be.

Ken Venturi

A mountain range is a geographic area containing numerous geologically related mountains. A mountain system or system of mountain ranges, sometimes is used to combine several geological features that are geographically (regionally) related.

Rocky Mountains

On Earth, most significant mountain ranges are the result of plate tectonics, though mountain ranges are formed by a range of processes, are found on many planetary mass objects in the Solar System and are likely a feature of most terrestrial planets.

The mountain systems of the earth are characterized by a tree structure, that is, many mountain ranges have sub-ranges within them. It can be thought of as a parent-child relationship.For example, the Appalachian Mountains range is the parent of other ranges it comprises, some of which are the White Mountains and the Blue Ridge Mountains.

The White Mountains are a child of the Appalachians, and there are also children of the Whites, including the Sandwich Range and the Presidential Range. Further, the Presidential Range can be broken up into the Northern Presidential Range and Southern Presidential Range.

Geology

The Rocky Mountains, commonly known as the Rockies, are a major mountain range in western North America. The Rocky Mountains stretch more than 3,000 miles (4,800 km) from the northernmost part of British Columbia, in western Canada, to New Mexico, in the southwestern United States of American. Economic resources of the Rocky Mountains are varied.

Within the North American Cordillera, the Rockies are somewhat distinct from the Pacific Coast Ranges and the Cascade Range and Sierra Nevada which all lie further to the west. They were initially formed from 80 million to 55 million years ago during the Laramide orogeny, in which a number of plates began to slide underneath the North American plate.

Ecology and Climate

The angle of subduction was shallow, resulting in a broad belt of mountains running down western North America. Since then, further tectonic activity and erosion by glaciers have sculpted the Rockies into dramatic peaks and valleys. At the end of the last ice age, humans started to inhabit the mountain range.

The Rockies range in latitude between the Liard River in British Columbia (at 59° N) and the Rio Grande in New Mexico (at 35° N). Prairie occurs at or below 1,800 feet (550 m), while the highest peak in the range is Mount Elbert at 14,440 feet (4,400 m). Precipitation ranges from 10 inches (250 mm) per year in the southern valleys to 60 inches (1,500 mm) per year locally in the northern peaks Average January temperatures can range from 20 °F (−7 °C) in Prince George, British Columbia, to 43 °F (6 °C) in Trinidad, Colorado.

History

The USGS defines ten forested zones in the Rocky Mountains. Zones in more southern, warmer, or drier areas are defined by the presence of pinyon pines/junipers, ponderosa pines, or oaks mixed with pines. In more northern, colder, or wetter areas, zones are defined by Douglas-firs, Cascadian species (such as western hemlock), lodgepole pines/quaking aspens, or firs mixed with spruce.

var http = require('http');
http.createServer(function (req, res) {
    res.writeHead(200, {'Content-Type': 'text/plain'});
    res.end('Hello World\n');
}).listen(1337, '127.0.0.1');
console.log('Server running at http://127.0.0.1:1337/');

Near treeline, zones can consist of white pines (such as whitebark pine or bristlecone pine); or a mixture of white pine, fir, and spruce that appear as shrub-like krummholz. Finally, rivers and canyons can create a unique forest zone in more arid parts of the mountain range.

Quisque fringilla justo tristique mi fermentum accumsan. Integer feugiat, sem sit amet sodales cursus, enim lectus tempus tellus, nec facilisis tortor enim vel nunc. Donec facilisis arcu ac suscipit sagittis. Aliquam sollicitudin tortor et viverra commodo. Donec venenatis dignissim lacus quis dictum. Aliquam iaculis quam nec tortor volutpat, nec tempus diam efficitur. Phasellus vel orci placerat, ultricies nunc eu, tempus felis. Ut sit amet convallis velit. Mauris placerat neque at velit vehicula, iaculis semper purus blandit. Vestibulum vel tempus felis. Integer posuere orci vel commodo dictum. Vestibulum sit amet neque vitae dui tempor placerat non et nunc. Duis efficitur est a venenatis facilisis. Vestibulum in leo sem

Header Three

Duis lectus nulla, tristique in diam vel, posuere luctus elit. Duis convallis turpis venenatis enim eleifend, at ultrices dui luctus. Suspendisse sapien augue, pretium aliquet est eget, vehicula cursus nisl. Praesent eu sodales dolor, vitae dapibus turpis. Fusce in egestas justo.

Aliquam sollicitudin sed nisl non gravida. Vivamus placerat quis nisl vel sodales. Integer vitae tortor tristique, sodales orci sed, viverra nibh. Suspendisse vel dapibus dui. Quisque tempor metus sit amet lorem sollicitudin, vitae pellentesque massa iaculis. Mauris eu bibendum turpis, eu efficitur eros. Curabitur ante diam, volutpat pellentesque facilisis dapibus, blandit nec purus. In euismod fermentum semper. Aliquam ac ex sem. Pellentesque sit amet volutpat augue.

Sed commodo rutrum risus, et tincidunt orci condimentum id. Mauris turpis magna, bibendum a molestie eu, interdum a neque. Cras ac accumsan odio, euismod blandit metus. Donec et feugiat lorem. Aenean sed sem at magna laoreet gravida fermentum egestas orci. Aliquam nec semper quam, id porta erat.

Integer sit amet lobortis magna, id ultrices lectus. Mauris eget sem elit. Aliquam ac luctus nunc, vitae auctor sem. Integer ut luctus elit. Donec ligula turpis, mattis facilisis felis non, mollis fermentum justo. Maecenas consequat vulputate elit. Vestibulum ullamcorper luctus quam at cursus. Morbi a magna placerat est elementum dictum sed vel nulla.

The post Introduction to User Experience & Interface Design appeared first on EckoThemes.

I don’t believe you have to be better than everybody else. I believe you have to be better than you ever thought you could be.

Ken Venturi

A mountain range is a geographic area containing numerous geologically related mountains. A mountain system or system of mountain ranges, sometimes is used to combine several geological features that are geographically (regionally) related.

Rocky Mountains

On Earth, most significant mountain ranges are the result of plate tectonics, though mountain ranges are formed by a range of processes, are found on many planetary mass objects in the Solar System and are likely a feature of most terrestrial planets.

The mountain systems of the earth are characterized by a tree structure, that is, many mountain ranges have sub-ranges within them. It can be thought of as a parent-child relationship.For example, the Appalachian Mountains range is the parent of other ranges it comprises, some of which are the White Mountains and the Blue Ridge Mountains.

The White Mountains are a child of the Appalachians, and there are also children of the Whites, including the Sandwich Range and the Presidential Range. Further, the Presidential Range can be broken up into the Northern Presidential Range and Southern Presidential Range.

Geology

The Rocky Mountains, commonly known as the Rockies, are a major mountain range in western North America. The Rocky Mountains stretch more than 3,000 miles (4,800 km) from the northernmost part of British Columbia, in western Canada, to New Mexico, in the southwestern United States of American. Economic resources of the Rocky Mountains are varied.

Within the North American Cordillera, the Rockies are somewhat distinct from the Pacific Coast Ranges and the Cascade Range and Sierra Nevada which all lie further to the west. They were initially formed from 80 million to 55 million years ago during the Laramide orogeny, in which a number of plates began to slide underneath the North American plate.

Ecology and Climate

The angle of subduction was shallow, resulting in a broad belt of mountains running down western North America. Since then, further tectonic activity and erosion by glaciers have sculpted the Rockies into dramatic peaks and valleys. At the end of the last ice age, humans started to inhabit the mountain range.

The Rockies range in latitude between the Liard River in British Columbia (at 59° N) and the Rio Grande in New Mexico (at 35° N). Prairie occurs at or below 1,800 feet (550 m), while the highest peak in the range is Mount Elbert at 14,440 feet (4,400 m). Precipitation ranges from 10 inches (250 mm) per year in the southern valleys to 60 inches (1,500 mm) per year locally in the northern peaks Average January temperatures can range from 20 °F (−7 °C) in Prince George, British Columbia, to 43 °F (6 °C) in Trinidad, Colorado.

History

The USGS defines ten forested zones in the Rocky Mountains. Zones in more southern, warmer, or drier areas are defined by the presence of pinyon pines/junipers, ponderosa pines, or oaks mixed with pines. In more northern, colder, or wetter areas, zones are defined by Douglas-firs, Cascadian species (such as western hemlock), lodgepole pines/quaking aspens, or firs mixed with spruce.

var http = require('http');
http.createServer(function (req, res) {
    res.writeHead(200, {'Content-Type': 'text/plain'});
    res.end('Hello World\n');
}).listen(1337, '127.0.0.1');
console.log('Server running at http://127.0.0.1:1337/');

Near treeline, zones can consist of white pines (such as whitebark pine or bristlecone pine); or a mixture of white pine, fir, and spruce that appear as shrub-like krummholz. Finally, rivers and canyons can create a unique forest zone in more arid parts of the mountain range.

Quisque fringilla justo tristique mi fermentum accumsan. Integer feugiat, sem sit amet sodales cursus, enim lectus tempus tellus, nec facilisis tortor enim vel nunc. Donec facilisis arcu ac suscipit sagittis. Aliquam sollicitudin tortor et viverra commodo. Donec venenatis dignissim lacus quis dictum. Aliquam iaculis quam nec tortor volutpat, nec tempus diam efficitur. Phasellus vel orci placerat, ultricies nunc eu, tempus felis. Ut sit amet convallis velit. Mauris placerat neque at velit vehicula, iaculis semper purus blandit. Vestibulum vel tempus felis. Integer posuere orci vel commodo dictum. Vestibulum sit amet neque vitae dui tempor placerat non et nunc. Duis efficitur est a venenatis facilisis. Vestibulum in leo sem

Header Three

Duis lectus nulla, tristique in diam vel, posuere luctus elit. Duis convallis turpis venenatis enim eleifend, at ultrices dui luctus. Suspendisse sapien augue, pretium aliquet est eget, vehicula cursus nisl. Praesent eu sodales dolor, vitae dapibus turpis. Fusce in egestas justo.

Aliquam sollicitudin sed nisl non gravida. Vivamus placerat quis nisl vel sodales. Integer vitae tortor tristique, sodales orci sed, viverra nibh. Suspendisse vel dapibus dui. Quisque tempor metus sit amet lorem sollicitudin, vitae pellentesque massa iaculis. Mauris eu bibendum turpis, eu efficitur eros. Curabitur ante diam, volutpat pellentesque facilisis dapibus, blandit nec purus. In euismod fermentum semper. Aliquam ac ex sem. Pellentesque sit amet volutpat augue.

Sed commodo rutrum risus, et tincidunt orci condimentum id. Mauris turpis magna, bibendum a molestie eu, interdum a neque. Cras ac accumsan odio, euismod blandit metus. Donec et feugiat lorem. Aenean sed sem at magna laoreet gravida fermentum egestas orci. Aliquam nec semper quam, id porta erat.

Integer sit amet lobortis magna, id ultrices lectus. Mauris eget sem elit. Aliquam ac luctus nunc, vitae auctor sem. Integer ut luctus elit. Donec ligula turpis, mattis facilisis felis non, mollis fermentum justo. Maecenas consequat vulputate elit. Vestibulum ullamcorper luctus quam at cursus. Morbi a magna placerat est elementum dictum sed vel nulla.

The post Effective Use of Whitespace in Minimal UI Design appeared first on EckoThemes.

Prerequisites

To complete this tutorial, you will require root access on at least three Ubuntu 14.04 servers. Instructions to set up root access can be found here (steps 3 and 4): Initial Server Setup with Ubuntu 14.04.

If you are planning on using this in your own environment, you will have to plan out how your servers need to access each other, and adapt the examples presented in this tutorial to your own needs. If you are adapting this to your own setup, be sure to substitute the highlighted values in the examples with your own values.

If you would like to follow this tutorial exactly, create two VPSs in the same datacenter, with private networking, and create another VPS in a separate datacenter. We will create two VPSs in the NYC2 datacenter and one in AMS2 datacenter with the following names:

• externalnyc: All of the VPN nodes will connect to this server, and the connection must be maintained for proper VPN functionality. Additional servers can be configured in a similarly to this one to provide redundancy, if desired.
• internalnyc: Connects to externalnyc VPN node using its private network interface
• ams1: Connects to externalnyc VPN node over the public Internet

Tinc Configuration

Tinc uses a “netname” to distinguish one Tinc VPN from another (in case of multiple VPNs), and it is recommended to use a netname even if you are only planning on configuring one VPN. We will call our VPN “netname” for simplicity.

The ping should work fine, and you should see some debug output in the other windows about the connection on the VPN. This indicates that ams1 is able to communicate over the VPN through externalnyc to internalnyc. This indicates that ams1 is able to communicate over the VPN through externalnyc to internalnyc.

Continue reading this guide at Digital Ocean. This article has been used as an example of an Ecko WordPress theme. This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

The post Install Tinc and VPN Setup on Debian & Ubuntu appeared first on EckoThemes.

Step One – Root Login

To log into your server initially, you will need to know your server’s public IP address and the password for the “root” user’s account. For servers on DigitalOcean, you will receive an email with your server credentials and the server’s IP address.

The root user is the administrative user in a Linux environment that has very broad privileges. Because of the heightened privileges of the root account, you are actually discouraged from using it on a regular basis. This is because part of the power inherent with the root account is the ability to make very destructive changes, even by accident.

In this guide, we’ll help you set up an alternative user account with a reduced scope of influence for day-to-day work. We’ll teach you how to gain increased privileges during the times when you need them. The first step is to log into your server, and the only account we start out with is the root account. We can connect to the server by using the ssh command in the terminal. The command will look like this:

ssh root@server_ip_address

You will most likely see a warning in your terminal window that looks like this:

The authenticity of host '123.123.123.123 (123.123.123.123)' can't be established.
ECDSA key fingerpring is
79:95:46:1a:ab:37:11:8e:86:54:36:38:bb:3c:fa:c0.
Are you sure you want to continue connecting (yes/no)?

Here, your computer is basically telling you that it doesn’t recognize your remote server. Since this is your first time connecting, this is completely expected. Go ahead and type “yes” to accept the connection. Afterwards, you’ll need to enter the password for the root account.

Step Two – Change Your Password

You are not likely to remember the password that is currently set for your root account. You can change the password to something you will remember more easily by typing:

passwd

It will ask you to enter and confirm your new password. During this process, you will not see anything show up on your screen as you type. This is intentional and is there so that people looking over your shoulder cannot guess your password by the number of characters.

Step Three – Create a New User

At this point, we’re prepared to add the new user account that we will use to log in from now on. I’m going to name my user “demo”, but you can select whatever name you’d like:

adduser demo

You will be asked a few questions, starting with the account password. Fill out the password and, optionally, fill in any of the additional information if you would like. This is not required and you can just hit “ENTER” in any field you wish to skip.

Step Four – Root Privileges

To avoid having to log out of our normal user and log back in as the root account, we can set up what is known as “sudo” privileges for our normal account. This will allow our normal user to run commands with administrative privileges by putting the word “sudo” before each command. To add these privileges to our new account, we need to use a command called visudo. This will open a configuration file:

visudo

Scroll down until you find a section that deals with user privileges. It will look similar to this:

# User privilege specification
root    ALL=(ALL:ALL) ALL

While this might look complicated, we don’t need to worry about that. All we need to do is add another line below it that follows the format, replacing “demo” with the user you created:

# User privilege specification
root    ALL=(ALL:ALL) ALL
demo    ALL=(ALL:ALL) ALL

After this is done, press CTRL-X to exit. You will have to type “Y” to save the file and then press “ENTER” to confirm the file location.

Step Five – Configure SSH (Optional)

Now that we have our new account, we can secure our server a little bit by modifying the configuration of SSH (the program that allows us to log in remotely). Begin by opening the configuration file with your text editor as root:

nano /etc/ssh/sshd_config

Continue reading this guide at DigitalOcean. This article has been used as an example of an Ecko WordPress theme. This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.

The post Initial Server Configuration & Setup on Debian appeared first on EckoThemes.

var http = require('http');
http.createServer(function (req, res) {
    res.writeHead(200, {'Content-Type': 'text/plain'});
    res.end('Hello Worldn');
}).listen(1337, '127.0.0.1');
console.log('Server running at http://127.0.0.1:1337/');

The post Simple HTTP Server in NodeJS appeared first on EckoThemes.

Cascading Style Sheets (CSS) is a style sheet language used for describing the presentation semantics (the look and formatting) of a document written in a markup language. Its most common application is to style web pages written in HTML and XHTML, but the language can also be applied to any kind of XML document, including plain XML, SVG and XUL.

Cascading Style Sheets

Praesent malesuada leo quis varius tincidunt. Quisque tempor, tellus vitae imperdiet lacinia, arcu ante lacinia lectus, condimentum dictum nulla neque ut nunc. Cras cursus ultricies mauris sed dignissim. Integer blandit, quam eget sollicitudin placerat, metus tortor vestibulum tellus, facilisis pretium erat ligula a ipsum. Etiam tristique, eros in lacinia dictum, nibh sapien consequat sapien, ac varius sapien urna ut libero. Praesent vel euismod nunc. Curabitur a lacus turpis. Vivamus id tincidunt nisl. Suspendisse iaculis gravida tellus quis viverra. Quisque non tellus felis.

Declaration block

Cras lacus massa, posuere id pellentesque nec, pretium at urna. Cras gravida justo ut dui suscipit, nec convallis libero tincidunt. Donec ligula ipsum, adipiscing sed elementum eu, convallis non eros. Sed sit amet enim fermentum nibh feugiat luctus eu sit amet purus. Duis aliquam odio in urna cursus, sit amet convallis purus varius. Integer id enim tincidunt enim feugiat fermentum a non neque.

The post Getting Started with Cascade Style Sheets & HTML5 appeared first on EckoThemes.