syslogd is the Linux system logging utility that take care of filling up your files in /var/log when it is asked to.

On a standard system, logging is only done on the local drive. But syslog can be configured to receive logging from a remote client, or to send logging to a remote syslog server.

Some of the use cases could be:

• A machine which filesystem goes read-only
• Log replication

this tutorial will explain how to set up both the server, to receive message from a remote client, and the client to emit messages to a syslogd server.

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3. Forwarding Internet traffic with IPtables

IPtables is both used to act as a firewall, but it is also the one passing packets from one network to another.

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2. DHCP server

In order to provide an IP address to the other machines in the network, we need to use a DHCP server.
This DHCP server will provide the host with all the information needed to connect to any other accessible host. i.e, the IP, netmask, gateway, domain name server.
The DHCP server will also update bind with a nt set of hostname and IP when the client is requesting a specific hostname.

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1. DNS server

As a DNS server we are going to use bind9, it will be configured to resolve the names of the host for our network lan.debuntu.local.

The DNS server will also accept dynamic DNS update from the local DHCP server.

In this tutorial, I will be using the Dynamic DNS feature of bind.

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Linux is a perfect platform to act as a router/gateway.

In this tutorial, I will explain how to set up a Linux box to operate as a network router. The box will provide the following services:

• DHCP server to provide the ip addresses to the machines in the LAN
• DNS server to resolve domain names
• Gateway with IP tables to give access to the Internet.
• Firewall with IP tables.

The resulting machine will have quite a small footprint: about 600M, and except if your network is intensively used, a low spec computer can be recycled to do the job.

As the machine is going to operate as a router/firewall

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When copying files over the network, the files informations can be modified.

When using cp, one can avoid this issue by using the -a which will do the copy in archive mode, meaning that it will keep the links, preserve mode, ownership and timestamps and the copy is recursive.

the solution to this over the network is rsync alongside with ssh.

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In the 2 previous articles, I explained how to set up a serial console on Ubuntu and Debian.

This tutorial will now show how to connect to those serial console using another machine using a software called minicom.

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This tutorial will go over the steps to go through in order to set up a serial console on Debian Linux.

Debian uses sysvinit to handle the booting process, amongst the different task, and as such, there is a few differences between most of the tutorial that you might find on the internet regarding how to set up a serial console.

A Serial Console becomes handy when running a headless server (i.e no keyboard and screen) or if you cannot connect a a server because of a network issue.

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This tutorial will go over the steps to go through in order to set up a serial console on Ubuntu Linux.

Unlike most other distros, Ubuntu uses upstart instead of sysvinit and as such, there is a few differences between most of the tutorial that you might find on the internet regarding how to set up a serial console.

A Serial Console becomes handy when running a headless server (i.e no keyboard and screen) or if you cannot connect a a server because of a network issue.

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SSH is great. There is so many thing you can do with it other than just a remote secure shell like X forwarding, port forwarding, authenticate using a private/public key, compress the transmitted stream….

If you have different account that you use on an every day basis, it becomes quickly cumbersome to type those lengthly command lines.

One could work around this by using aliases, the right way would be to use ~/.ssh/config

This tutorial will show some customization examples that should cover most ssh use cases.

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