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Thursday, April 28, 2016

Make Money While You Sleep

There are a lot of apps for making money with your smartphone or tablet. It doesn't matter whether you use iOS or Android. Money Making Apps are almost everywhere. Today I want to tell you about an app called Swagbucks TV from Swagbucks. The Swagbucks TV app which pays you for watching videos and is available on both iOS or Android.

Well how does it work?
In order to start earning money you need to signup for an account with Swagbucks. You can use the app to to create an account, but I would sign up for an account on the Swagbucks website, because it is easier. The app plays an ad and then plays a video. This continues until you stop the player. The app sometimes puts a cap on how much you can earn a day or in one sitting. After you're signed in your account you select a category and start a video. The categories are Featured Videos, Recipes (cooking), Entertainment, Fashion, Health, Home and Garden, Music, News, Travel, and Celebrity. If you like any the watching videos for the above mentioned, great enjoy making little money with this app.

How do you make money while sleeping?
Before you go to sleep start playing videos with the app. Turn off the sound and turn down the screen brightness. When you wake up you earned some coin. You can also play some videos on your computer from the Swagbucks website as well, if you really want to milk this thing.

Links to apps

Swagbuck TV for iOS
Swagbuck for iOS


Swagbuck TV at Google Play
Swagbuck app at Google Play



Wednesday, April 27, 2016

How to install or upgrade Java in Linux (Updated)

In this blog post I show how to install or update Java from Oracle on a Linux server. Many Linux distros use the OpenJDK version of Java in their operating systems and in their repository. Although the instructions below will still work to install OpenJDK, the focus is on Oracle's version of Java.

When using the Java provided by Oracle, you can download it from Oracle's website or from java.com. From there they give you a choice of downloading rpm or tar files. I prefer to use Red Hat Package Manager (RPM) files instead of the tar files when installing any program.

You can download Java here: www.java.com

Find Java on the system.
root@earth> find / -name java -type f
/usr/java/jre1.7.0_101/bin/java

Note - If you use which or java -version commands to find Java on your system. This will only show your the system's main java. You may have additional versions installed.

Now take each line of output and paste it at the end of the rpm -qf command. This gives you the name of the rpm package that installed that instance of Java.

root@earth> rpm -qf   /usr/java/jre1.7.0_101/bin/java
jre-1.7.0_101s

If the Java found on the system was not installed via a package, then Java was installed via a tar file. At this point you must decide whether to install the new version of Java with an rpm or a tar file. I recommend the use of the rpm packages to install any programs. If you are installing with a rpm then go to the section titled Installing Java using RPM. If you are use the tar file then skip to the section titled Install Java using a tar file.

Installing Java using RPM
The rpm command can either update an existing package or install a new one.

The documentation on the Java website says to remove/uninstall the old version of Java and then install the new one. I prefer to install or upgrade though. This is because if there are any symlinks or application settings that use the systems' Java, will be updated to use the newer Java. Then you can remove the old version if needed after the fact. Otherwise you would have to recreate these items after the install.

Updating Java using RPM 
If you update Java as shown below then you will not need to remove the old version. Unless you are installing a different version of Java. For exampe If you have Java 7 installed and then you install Java 8
root@earth> rpm  -Uvh   jre-7u111-linux-x64.rpm

You can alternately install Java instead.
root@earth> rpm  -ivh   jre-7u111-linux-x64.rpm

Uninstall the old package.
Take the output from the last command and use the rpm command with the -e option to remove the package.
root@earth> rpm -e  jre-1.7.0_65cs

Note- Do not run the above command for java that is part of an application. If the file was in /usr/bin/ you should be fine.

Install Java using a tar file
Change directory to where Java is going to be installed. Usually it will be /user/java.
root@earth> cd  /usr/java

Note - If your upgrading Java with a tar file, it is advised to backup the old installation and to remove the previous version. If the old version was installed via a tar then remove the directory. If it was installed with a rpm file use the rpm or yum command to remove the package. 

Move the tar file to /usr/java and unpack the tarball to install Java
root@earth> tar  zxvf   jre-7u111-linux-i586.tar.gz

Delete the tar file after you test Java and your done.

Reference:
Java.com

Related posts on this Blog
How to install or upgrade Java in Linux
How to install Java 7 & 8 on Solaris
Access the Java Control Panel
Updating Java on Solaris

If you have any questions or comments please post them below.

Tuesday, April 26, 2016

Manually Update Plugins for your PVS

I had an issue the other day with one of my Passive Vulnerability Scanners (PVS) which is being managed by Security Center. In Security Center the status of one of the PVS scanners showed "Plugin Out of Sync". I tried to push the plugins to the PVS scanner from the Security Center, but I was getting a status error of "Connection timed out".  So basically I was getting a latency issue on the connection. The PVS scanner and the Security Center are in different states, so this may be why there is so much latency. I just built this PVS scanner, so there were just too many plugins to be pushed over the wire by Security Center. To fix this issue, I just manually copied the plugins to the PVS scanner. Then I manually loaded the plugins into the PVS scanner. After I did this, I have not had this issue again.

Follow the instructions below to manually install plugins for the PVS scanner.

1. Login to the PVS scanner.
root@earth> ssh pvs

2. Stop the PVS service.
root@nessus> service pvs stop

3. Load the plugins into PVS.
root@nessus> /opt/pvs/var/pvs --update-plugins  plugins_file.tar.gz 

4. Start the PVS service
root@nessus> service pvs start

5. Login with an admin account to the web interface for the Security Center and check the status of the PVS.

You're done.

If you have any questions or comments please post them below.

Related post on this Blog
Manually Update Plugins on a Nessus Scanner
Reset Admin account on Security Center
How to Reset a Nessus Scanner

Friday, April 22, 2016

Linux User Account Creation & Customization

A Systems Administrator must be able to manage user accounts by adding users, removing users, modifying accounts and setting passwords. In this tutorial, I will be giving you instructions on how to properly create user accounts on Linux operating systems. Creating a user account can be simple, but there are a few complexities to note. As opposed to a graphical user interface (GUI), these instructions use the command line to create the user accounts.

The command line provides an ideal method for account management, because it provides faster account creation, especially when you are creating several accounts on one more computers. The graphical user interface or GUI on Linux Systems can vary greatly from system to system, but the one constancy on all Linux operating systems is the command line. The command line (CLI) is a text based user interface used for entering commands for the operating system to decipher. So I will be showing the use of the useradd command which creates the user accounts, and the passswd command which sets or changes the user accounts password.

Typographical conventions.
The typographic convection section is meant to help readers better understand what it is their seeing. Please carefully read the instructions before continuing.

The courier font is used for names of commands, files, directories, user names, and on-screen computer output; for example:
Use the useradd command to add users to the computer.

The courier bold font is used for characters and numbers you type; for example:
whoami

Courier bold italic is used to represent variables that can change; for example:
passwd bob


Instructions
After each line you type into the command line press the enter key. As explained in the above typographical conventions section, anything displayed in courier bold is typed in the command line and if it is displayed in courier it is the output of the line above. To follow this tutorial open the terminal or xterm program to access the command line. Please refer to the Command & Term Reference guide, for information on commands and terms.

Note - If you don't have access to a Linux computer you can still follow along, using the Linux emulator at, "http://www.tutorialspoint.com/execute_bash_online.php" . Type the commands into the green box on the right.


Method One: Create a user, using default settings.
If you are creating a user account on just one computer, the steps below will work, but if you are creating a user account on more than one computer, use method two or three instead. If the Linux computer is not connected to any other Linux computers on the network then the method shown below will work. This the best method to of users who are novices at using the command line.

Follow the steps below to create a user account for Bob.
1) Create user account for bob
useradd bob

2) Create a password for user account bob.
passwd bob
passwd: Changing password for bob
New Password:
Re-enter new Password:
passwd: password successfully changed for bob

The passwd command sets user account passwords. In the example above it sets the password for user account bob.

Note - If you don't set the password, the user will not have a password and will not be able to log in.

3) Test user account by logging into the computer with the new user account.
su – bob

The su command stands for switch user, and it is used to switch from one user account to another. The is an option used with the su command, it allows you to fully switch to the new user account. In order to fully test the newly created user account you must use the su command with the option, as shown.

4) Verify you are logged in as new user.
whoami
bob

The whoami command displays the name of user currently logged in on the command line. The result of the command should be bob as shown above.

Fun Fact: The whoami command also works on Windows computers.

Creating a user account using this method was pretty easy right? This method is perfect for home users who want to add user accounts to their home PC, for their family and friends. This method is not the way to add users on a corporate network.

Method Two: Creating a user with custom setting.
This method is all about control, and is used when creating user accounts on corporate networks. One positive thing about this method is that you know exactly what is being set. The downside to the method is the high probability of making a typo. This method can be too complicated for less knowledgeable users.

1) Create the user account.
Type the entire line out before you press enter.
useradd -u 900 -g users -G video  -c “user account, Jill” -m -d /export/home/jill -s /bin/bash jill

Command Options Explained
-u        Sets user’s UID (Unique Identification Number) to 900
-g        Sets user’s primary group to users
-G        Sets user’s secondary groups to video
-c        Sets a comment for the user. Puts a comment into the /etc/passwd file.
-m        Makes the user’s home directory
-d        Sets the path to the user’s home directory
-s        Sets the user’s shell

One reason to use useradd with all the options listed above is because computers see user accounts as numbers. When we created Jill’s user account we see the account’s name as being jill, but the computer sees the account’s name as 900 or UID (Unique Identification Number) 900. Unless you set the UID by using the –u option the computer will assign the next available UID number which could result in a user having different UID numbers on different computers. This can cause issues with permissions, for example if user Bob has UID 900 on PC number one and Jill has the same UID on PC number two. Jill creates a document and stores it on the network. PC one will see that file is owned by UID 900 and so it will show Bob as the owner. Then Bob can do anything he wants to Jill’s document, including deleting it.

Note: For more information on the useradd command and it options, type man useradd into the command line. To exit the man page


2) Set Jill’s password. 
echo jillspassword | passwd -e jill –stdin

In the above series of commands, the echo command sends the word jillsmypassword to the passwd command, then the passwd command sets the user’s password to jillsmypassword. The –e shown in the above example, expires the user’s password, making the user have to change their password when they attempt to login.

Why set the password in this way, the way shown in Method one was easier? This method is a more advanced way to set a user’s password. For example, let’s say you need create ten user accounts. If you do what we did in Method one, you will need to type the new user’s password in twenty times, two times for each user. On the other hand if you use the method show here, then you only need to change the username ten times. To save on typing, the rest of the command shown above can be pasted into the command line. This method can also be used in a script, since it doesn’t require any additional input from you after you run the command.

3) Repeat steps 3 &4 from Method one to test the account.

Method Three: Configuring system settings for easier user creation.
In Method three, I will be combining the ease of use of the first method and the completeness of the second. In Method one we ran the useradd command with no options set. The Linux system still used many of the options used in Method two, but set them using system defined defaults. To see these defaults for the useradd command with the –D option; for example:
useradd -D
GROUP=2001
HOME=/home
INACTIVE=35
EXPIRE=
SHELL=/bin/bash
SKEL=/etc/skel
CREATE_MAIL_SPOOL=yes

To change the default system setting run useradd –D followed by the setting you want to change. In the example below, the default shell is being changed to /bin/ksh from /bin/bash.
useradd –D –s /bin/ksh

To see if the changes took effect, run the useradd –D command again.

Note: The most common things to set is the home directory, and the shell.

1) Create user account for Sam
useradd -u 1010 -G 10 -c “user account, Sam” -m sam

Here we have the best of both words, the less typing of Method 1 and the precise settings from Method two. Setting the system defaults will allow much less of a chance of making mistakes. Now only the setting that are unique to the user will have to be set.

2) Set Sam’s password, choose the approach used in Method one or Method two.

3) Repeat steps 3 & 4 from Method one to test the account.

I showed you three variations, on using the passwd command to create user accounts. For new users on Linux, I suggest they use Method one. Intermediate to advance users should use Method two or three, though Method three is the preferred method. I hope this tutorial was informative and you learned something new.

Command & Term Reference Guide

Commands
useradd – command used to create user accounts.
passwd – command used to set user account passwords.
whoami – informs user who they are logged in as. Can also use the command id to do the same thing.
su – stands for switch user, and is used to switch between users.
man – stands for manual, used to view system manuals. The manuals are referred to as man pages.
echo – displays whatever you type on the next line.
|  - This is called a pipe, it takes the output of the command on the left and sends (pipes) it to the input of the command on the right.

Terms
Terminal and xterm: are programs that display the command line. The terms xterm, terminal and command line can, for the most part, be interchangeable.
Shell: is a customized command line environment. Examples of shells are BASH, SH, KSH and CSH.

Conclusion
Well what did you think? This post is written at a lower level than most of my other posts, because this was originally a paper I wrote for a college class. Method 3 needs a little more info, so I will write a follow on post with a little more detail on how to set the system defaults. Anyway let me know what you think and if you have any questions by posting below.

Related posts on this Blog
Adding a new user to a UNIX based system

References
Man pages: useradd, passwd
My Collage paper
The Ultimate Guide to Create Users in Linux / Unix


Tuesday, April 12, 2016

A Better Way to Setup SSH Keys

Note - I have a newer version of this how-to. Please click here 

This is a guide on setting up SSH Keys for a Linux based user account. Why set up SSH keys, why not just use your password? SSH Keys are considered more secure than using passwords to access systems, because user accounts are authenticated by the server without ever having to send your password over the network. If the passwords are not transmitted then they can't be intercepted. This works by identifying yourself to an SSH server using public-key cryptography and challenge-response authentication. Not to mention if you set up a SSH agent then the agent will handle the challenge-response authentication for you.

This guide is not for installing or setting up a SSH server. You must have sshd service running on your servers in order to get your SSH to work. All the examples are take from a Red Hat or Suse servers. The ssh-copy-id command will not work on Solaris servers but all other commands should work file.

Create you key pair
The ssh-keygen command will generate a public and private keypair. The keys will be stored at ~/.ssh.The basic command looks like this: ssh-keygen -t [dsa|rsa]  The -t sets the type of keys used. In the example below I create a rsa key pair.
man@earth> ssh-keygen -t rsa
Enter file in which to save the key (/home/man/.ssh/id_rsa): Press [Enter] key
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/man/.ssh/id_rsa.
Your public key has been saved in /home/man/.ssh/id_rsa.pub.
The key fingerprint is:dfhjodfnk
04:be:15:ca:1d:0a:1e:e2:a7:e5:de:98:4f:b1:a6:01

Make sure you don't use a blank passphrase. Doing this is very insecure. Having a blank passphrase defeats the purpose of having having the extra security of a key exchange setup. It is also import to never give out your private key, which also compromises security of your account.


The old way of transferring the public key to the remote sytem.
man@earth> scp ~/.ssh/id_rsa.pub moon:~/.ssh/authorized_keys

New way
man@earth> ssh-copy-id user@moon
Now try logging into the machine, with "ssh 'remote-host'", and check in:

.ssh/authorized_keys

to make sure we haven't added extra keys that you weren't expecting.
The reason the new way is better then the old way is that the ssh-copy-id appends the public key to the authorized_keys file. Where as the old way overwrites the authorized_keys file. This allows the account to use keys from more than one server.

Note- This method will not work on Solaris 10


If your home directory automounts across a lot of servers. You can copy it over with the cat command.
man@earth> cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys


You can also use this method if the ssh-copy-id command is not available to you.
man@earth> cat ~/.ssh/id_rsa.pub | ssh man@moon "mkdir -p ~/.ssh  &&  cat   >>  ~/.ssh/authorized_keys"

Setting up the SSH Agent.

man@earth> eval `ssh-agent`
man@earth> ssh-add
Enter passphrase for /home/man/.ssh/id_rsa:
Identity added: /home/man/.ssh/id_dsa (/home/man/.ssh/id_rsa)

Note- Add these commands to the .bashrc file to start an agent automatically when you login to a server. 

There are other ways to set up the agent, such as using the gnome GUI for example. If you use VNC, just start your VNC server session in the same terminal you used to starting your agent. This way all your terminals launched in your VNC session, will use the same agent.

SSH Agent Management
One issue with agents is that sometimes you end up running a lot of agents. Run the command below and kill any agents that you are not using.

man@earth> ps aux | grep agent
If there is more than one agent running then you should kill the additional ssh-agent.

man@earth> pkill ssh-agent
This will only kill agents owned by the user running the command in.

One way to kill your ssh-agents is to add a kill statement to the .bash_logout file.

Reference Section
Manpage ssh-copy-id

Related posts on this site.
How to setup SSH Keys
http://rich-notes.blogspot.com/2013/09/how-to-setup-ssh-keys.html

If you have any questions or comments please post below.