1. Gather/Setup the Internal IP addresses on all the computers that you will be networking.

On the system tray, right click on the Network Manager icon and select “Connection Information”. Depending on your connection type, the network manager icon might display an icon with a pair of linked computer (for cable connection) or an icon with the wireless status (for wireless connection). This window will show you all of the network information you will need for the device, including its IP address.

Setup a static IP or reserve addresses

Since most PC’s and routers use DHCP by default to get internal IP addresses automatically, there is a chance that the IP address for a device may change if it is rebooted or if the lease is renewed. This can cause the network share to disconnect. There are two ways to resolve this:

• In your router settings, you can set a reserved IP address for a specific physical address (MAC address)
• You can create a static IP for the network interface.

I use static IP’s for my devices and will show that procedure in this article. If you want to reserve IP addresses in the router, you will need to check your particular router’s settings. Each router is different but should have a setting to reserve a specific IP address for a specific MAC address.

To set up a static IP in Linux Mint, right-click on the network manager icon in the system tray and select “Edit Connections”. Choose the “Wired” tab if the PC is connected via network cable or “Wireless” if connected by wireless. Highlight the correct interface or wireless network and click “Edit”.

In the “Edit” window, select the IPv4 tab. Click the drop-down and select “manual”. Then edit the IP address, NetMask, and Gateway information. You need to make sure the IP address for each device is unique. I normally just use the current IP that was given via DHCP and make sure it becomes the static IP. You can use any numbering scheme you like as long as they are unique. After all the information is entered, click Apply and from that moment forward that device will always have the IP address that you manually typed in.

2. Install the SSH Server on each device.

SSH is secure and easy to use. The SSH client software is installed by default, but the server is not. If you want to be able to connect to a specific device, that device must have SSH Server installed. If you never want to connect to a specific device you can skip this step. You’ll be able to connect from that device to another device in that case (client to server).

To install OpenSSH Server, open your terminal and type:

sudo apt-get install openssh-server

Type in your sudo password and the SSH server will install. That’s all there is to it!

3. Configure the Firewall settings on each Device

You will need to set the Firewall settings on each device to allow traffic to come in from the other devices. Go to the “Menu -> All Applications -> Firewall Configuration” or at a command line, type:

gufw

This will bring up the GUI frontend to the ufw firewall. Click “Add” and click the Advanced tab. In the “From” box, type in the IP address of the device that will be connecting to this device, and in the “To” box, type in the address of this device (the device whose firewall settings you are now configuring). Click “Add” and you will see the rule in the main window. In this example, IP 192.168.1.104/tcp is the computer that I am setting the firewall configuration on and the rule is allowing traffic from the device at 192.168.1.109.

Add rules for any other devices that will need to connect/share with this device to ensure the firewall will accept traffic and file sharing.

4. Connect to Each Device/Desktop/Laptop.

After SSH is installed and all firewall settings are correctly configured, it’s the moment of truth; now we will create connections via SSH to the device that we want to share with.

Let’s say that the device on 192.168.1.109 is a laptop and we’re connecting it to 192.168.1.104 which is a desktop.

1. On the laptop, open the Nautilus file manager.
2. Click on “File -> Connect to Server”.
3. In the “service type” drop-down, select SSH.
4. Type in the IP Address of the device you wish to connect to, in this example: 192.168.1.104. Then click Connect. If it finds to device correctly, you will see a login window. Type in your username and password for the device you are connecting to and select “Remember forever”.

5. Linux Mint will then mount a folder directory to the computer at the IP address you named and a File Directory window will open allowing you to browse the networked computer’s folders and files.

5. Create a Folder Shortcut.

Once you have access to the remote/networked computer, you can create a shortcut folder in the left sidebar of the File Manager window. Simply drag a folder into the left sidebar (I normally drag the “Home” folder from the remote computer). You can then rename the folder to something meaningful, such as “Desktop_Home”. Now anytime you click on this folder, it will connect to the networked computer and you can access its directory. Since you saved the password, you will not need to login again, unless the password is changed in the future.

6. Rinse and Repeat

Now you can simply repeat the process on the other devices and create the shortcut folder on each one. Whenever you want to share across device, you can connect via the shared folder shortcut (providing the other device is on, of course!).

Though it involves a few steps, I found this is one of the easier ways to access folders and files amongst my desktops and laptops at home that are all running Linux Mint. What other ways do you use to create a home network?

Image credit: By Lars P.

The post Setting Up a Home Network with Linux Mint appeared first on Make Tech Easier.

Installation

To install sysstat on a RedHat based variant using yum:

yum -y install sysstat

To install on a Debian based variant using apt:

apt-get install sysstat

If you are using a Ubuntu-based distro, you should be able to find sysstat in the software manager.

After the installation, you will need to edit the configuration file to run the daemon.

In the terminal:

gksu gedit /etc/default/sysstat

and set the “sadc” variable to true by changing the line to ENABLED="true".

Save and close the file. Finally, start the daemon:

/etc/init.d/sysstat start

Common usage of Sysstat

The sysstat suite is obviously a collection of very extensive and detailed application. Here are some basic ways to use the tools in order to gain a feel for its troubleshooting guidance.

Check CPU usage

To check CPU usage stats for the current day (by default sar tracks the data every 10 minutes):

sar -u

To display real-time CPU usage for a given amount of time, you can specify the intervals in seconds followed by how many entries you want to report. For example: the following will report total CPU usage every 2 seconds for a total of 10 times:

sar -u 2 10

Most PCs have multiple cores nowadays. To view the activity of each specific core use the “-P ALL” flag. The following shows a real-time snapshot of the 4 cores in my PC (same intervals and output parameters apply, below is 1 second 1 time):

sar -P ALL 1 1

Want to see how much memory is currently being used? Use sar -r as follows to show real-time memory usage every 2 seconds for 10 times:

sar -r 2 10

Display device report

To display a device report showing transfers per second (tps) and data read and write stats, showing data in real-time every 2 seconds, for 10 reports, type:

iostat -d 2 10

Note:

• tps = transfers per second
• Blk_read/s = amount of data read in blocks per second
• Blk_wrtn/s = amount of data written in blocks per second
• Blk_read = total blocks read
• Blk_wrtn = total blocks written

For extended I/O stats:

iostat -x 2 5

Get information regarding running process

Use pidstat to report information regarding running process. The -d flag will list all processes on the machine:

pidstat -d

To see real-time results of running processes, you can use the following, where like the above examples, the first number is the second interval and the second number is how many times to report:

pidstat - d 2 5

Another useful command is to use pidstat with the -r flag to analyze memory usage with particular processes:

pidstat -r 2 5

Conclusion

Sysstat is a very powerful monitoring tool for Linux and it is particularly useful in a server environment where there is no GUI available. The above mentioned only touch the surface of what sysstat is capable. If you have used sysstat in your PC/server, feel free to share with us the various ways you use it to monitor your system performance.

The post How to Monitor Your Linux Performance With Sysstat appeared first on Make Tech Easier.

• 10 annual license: $139.00
• 50 Annual License: $199.00
• 100 Annual license: $299.00
• 250 annual license: $399.00
• Unlimited: $499.00
• Unlimited Lifetime: $999.00

The Virtualmin download page list the steps to install Virtualmin on your server.

Note that Virtualmin has a setup script that makes installation easier, but it will only work with certain operating systems (Virtualmin calls them grade A):

• CentOS 5 and 6 on i386 or x86_64
• RHEL 5 and 6 on i386 and x86_64
• Scientific Linux 6 on i386 and x86_64
• Debian 6 on i386 or amd64
• Ubuntu 8.04 LTS and 10.04 LTS on i386 or amd64

You can use Virtualmin with other server OS’s, but the script will probably not work, which makes installing a bit more of a hassle. There is a way to “fake” the install script to thinking it’s installing on a grade A OS. For example, if you want to install Virtualmin on Ubuntu 11.10, a simple change will make the install.sh script think it’s being installed on versions 10.04 LTS. (no guarantees that this will work with every system)

nano /etc/issue

replace “Ubuntu 11.10 \n \l” with “Ubuntu 10.04.02 LTS”

Save the file (Ctrl + o) and exit (Ctrl + x)

Note: The Ubuntu LTS (long term support ) releases are considered grade A by VirtualMin, but as of this writing Ubuntu’s 12.04 LTS is not listed.

Install Virtualmin

Download the script:

wget http://software.virtualmin.com/gpl/scripts/install.sh

or

curl http://software.virtualmin.com/gpl/scripts/install.sh

Make the script executable:

chmod u+x install.sh

Run the install script:

/bin/sh install.sh

As long as you have a grade A system (or at least fake that you have one), the script will handle the entire install process. When it’s finished, all you need to do is open a browser and go to port 10000 on that server:

https://yourdomain.com:10000

What can you do with Virtualmin? Pretty much everything. There is a dashboard where you can see all the running processes and services. You can customize it to show you the data you want to see. An administrator can easily use Virtualmin’s interface to do almost every task imaginable: Modify DNS settings, configure email settings, schedule backups for all of your virtual servers, manage plugins and applications, manage services, and much more.

Screenshots

Try Virtualmin yourself by using the free online demo.

The post Virtualmin Review: A Free Web Server Control Panel appeared first on Make Tech Easier.

There are other GUI apps built to easily edit cron, such as Gnome-Schedule. However, if you don’t want to install any new apps Corntab is a great web based solution, especially if you are setting up a cron job on a computer that doesn’t have Gnome-Schedule, or isn’t compatible with it.

The uses for cron are pretty obvious, anything from scheduling backups to running custom scripts at specific times, to opening programs on a schedule, cron is the way to get it done.

Let’s start with scheduling a task that simply creates a timestamp every minute to a log file, first using the shell/command line. Then we’ll run through the same steps using Corntab, so you can see how easy it is to use. Creating a timestamp or any output to a log file is a great way to test that your settings in cron are working, and of course to monitor your schedule going forward.

Open a terminal. Before we start, it is best to know where to go for information. The manual for crontab can be found by typing:

man crontab

Sure, you can Google and find other tutorials and probably the manual pages online, but it’s always good to know your way around the command line!

The syntax for cron is as follow:

crontab [ -u user ] file
crontab [ -u user ] [ -i ] { -e | -l | -r } [-s]

• -l option causes the current crontab to be displayed on standard output.
• -r option causes the current crontab to be removed.
• -e option is used to edit the current crontab using an editor specified by the VISUAL or EDITOR environment variables.
• -u option specifies the name of the user whose crontab is to be tweaked. If this option is not given, crontab will use the current user who is executing the command.
• -s option appends the current SELinux security context string as an MLS_LEVEL setting to the crontab file before editing / replacement occurs (see the documentation of MLS_LEVEL in crontab. This is not used in all variations of Linux/cron).

Note that some programs need to be executed with root privileges.  When this is the case, you will need to change to the root user with the su command, or the sudo command which should work in most Linux variations (Debian, Ubuntu, Fedora).

To edit your crontab type:

crontab -e

or

sudo crontab -e

Some ground rules for cron

• A field may be an asterisk (*), which always stands for “first-last”.
• m -minute (0-59)
• h -hour (0-23)
• dom -day of the month (1-31)
• mon -month of the year (1-12)
• dow -day of the week (0-6 with 0=Sunday)
• command -application, script, etc

Advanced Short codes:

string         meaning
——         ——-
@reboot        Run once, at startup.
@yearly        Run once a year, “0 0 1 1 *”.
@annually      (same as @yearly)
@monthly       Run once a month, “0 0 1 * *”.
@weekly        Run once a week, “0 0 * * 0″.
@daily         Run once a day, “0 0 * * *”.
@midnight      (same as @daily)
@hourly        Run once an hour, “0 * * * *”

Comma-separated values can be used to run more than one instance of a particular command within a time period.

Dash-separated values can be used to run a command continuously.

Let’s set up our cronjob.

If you are first entering crontab you will probably be given a choice of editor to use. Feel free to choose any, but I normally stick with nano since it is simple, clean, and gets the job done.

To accomplish our original task, simply type:

* * * * * echo "The current minute is: $(date)" >> /tmp/minute.log

“Control-x” will prompt to save, then enter will confirm. You should see that cron was successfully updated. The job will print the current date/time every minute to a file called minute.log in the /tmp directory.

Here’s the automatic output for 6 minutes:

Let’s get fancy, how about printing the date every 2 minutes…

*/2 * * * * echo “The current minute is: $(date)” >> /tmp/minute.log

Using */n where n is a positive integer will say every n minute, or every n hours.

How about printing the date at 5:30am every Monday and Friday:

30 5 * * 1,5 echo "The current minute is: $(date)" >> /tmp/minute.log

Feel free to play around with scheduling simple “echo” to logfiles. Then move up to scripts and applications.

Playing with Corntab

Now let’s try out CornTab, the web based cron editor that will take care of the syntax while we just click the options.

Here’s a step by step to create a crontab that will print the current date/time every two minutes, only in January, February, March, and April, on Thursday’s and Friday’s.

First, click “every n minutes” and move the slider to 2 minutes.

Next, click to expand month, click to select “each selected month” and select Jan, Feb, Mar, Apr.

Next, click to expand Day of Week, select “each selected day of the week” and select Thu and Fri.

Finally, click to expand Command and type in the code/script. Then you can copy the full cron code from Corntab and paste it into your crontab by using the steps at the beginning of this article.

References and more information about Cron:

http://www.pantz.org/software/cron/croninfo.html
http://www.computerhope.com/unix/ucrontab.htm
https://help.ubuntu.com/community/CronHowto

The post How to Schedule Tasks with Cron and CornTab [Linux] appeared first on Make Tech Easier.