LABS

During the Red Hat exams, the tasks will be presented electronically. Therefore, this book presents most of the labs electronically as well. For more information, see the Lab Questions section toward the end of Chapter 15. Most of the labs for this chapter are straightforward and require a very few commands or changes to one or two configuration files.

Lab 1: Install and Start Samba

In this lab, you'll install and set up Samba just for basic operation. If possible, use a system where Samba isn't already installed.

1. Ensure that appropriate Samba packages are correctly installed. What RPMs did you install and how did you install them?

2. Make sure the samba-client, samba-winbind, samba-doc, and samba-swat packages are also installed. There's no need to install Samba version 4 packages.

3. Make sure any local firewall supports access to the local Samba server. Make sure that the firewall on any clients supports the use of Samba client software.

4. Use one of the available service management tools to ensure that the Samba services are configured to start correctly when you boot Linux. What tool did you use?

5. Start Samba services now. You can use either the service management script located directly in /etc/init.d or the service command.

6. Verify that Samba services are running. How did you do this?

Lab 2: Review Samba Documentation

During an exam, or perhaps a trip to a remote site where Internet access is not possible, you may need to rely on the Samba documentation available with the installed packages.

1. Open the man page for the Samba configuration file, smb.conf.

2. Make sure that you know how to search for key directives, such as hosts allow and invalid users.

3. Open a Web browser, and navigate to file:///usr/share/doc/samba-doc-3.5.4/htmldocs/. Depending on the installation, the version number of the documentation may vary.

4. Select the Samba3-ByExample link. If a list of files appear, select the index.html link.

5. Scroll toward the bottom of the file. You'll see an entry with a "List Of Examples." Select a desired example.

6. Scroll through the examples. You'll see a number of examples of stanzas with shared directories. Review the examples. You'll learn more about Samba.

Lab 3: Configure Samba Global Settings

Before starting this lab, it's important to back up the /etc/samba/smb.conf file. Unless you do so, it may be difficult to proceed with additional labs in this chapter.

1. Use the SWAT web-based tool to configure the Samba service. Start this tool. If you didn't log in as the root user, did something happen before the tool started? Be sure to back up the current version of the /etc/samba/smb.conf file.

2. Configure Samba global settings to provide workgroup services to local users. Set the workgroup name to something appropriate for a local organization.

3. Can you limit access to a corporate domain name (such as example.com) through this tool? If you have to edit the Samba configuration file directly, what do you have to do?

4. Can you prevent access to one specific host or IP address through this tool? If you have to edit the Samba configuration file directly, what do you have to do? Do so for one host on the local network. If you've already run Lab 1, this task may already be complete.

5. Commit your changes. What do you need to do to make Samba reread the configuration file?

6. Test the result, first from the prohibited host specified in Step 4, and then from a second host on the local network.

7. Bonus lab: take the steps required to reinstall Samba and the associated original version of the smb.conf configuration file.

Lab 4: Configure a Share to a Home Directory

In this lab, you'll customize the default [homes] share for specific user-based security requirements. You'll need one common user on both the local Samba server and a remote Samba client.

1. Open the main Samba configuration file.

2. Navigate to the predefined [homes] share.

3. Ensure that the [homes] share is available only to hosts on the local example.com network. Alternatively, you can allow access to all systems on a local network, except for one IP address.

4. Ensure that the share is writable to one authenticated user.

5. Commit changes to the main Samba configuration file.

6. Set up that one user in the Samba password database.

7. Test the result from a remote system. If possible, test the result from systems both within the example.com network and outside that network. Alternatively, make the tests from systems that are supposed to be allowed and denied as configured in Step 3.

Lab 5: Configure a Share to a Public Directory

In this lab, you'll go a step further and create a public share accessible to all users.

1. Create a new share called [public].

2. Change the path to the public share to /home/public.

3. Configure the public share so that anyone in the local example.com domain can access the share.

4. Create the /home/public directory as required. Change the permissions to this directory to 1777.

5. What is the advantage of 1777 permissions?

6. Commit your changes.

7. Test the result from a remote system. What happens if you write a file to that shared directory?

Lab 6: Configure a Shared Network Directory, Limited to a Group

In this lab, you'll go even further and create a shared directory, with access limited to a group of two users. The basic steps are the same as Lab 5; however, you'll need to create a directory with SGID permissions, along with full permissions to the group owner of that directory. The basic steps to create that shared directory are the same as that created in Chapter 8.

Lab 7: Persistency Check

It is important for a server that any changes made are persistent. This means that changes should be active when you reboot Linux. Perform an orderly reboot of the local server now and verify that Samba starts when you boot Linux.

1. How did you make your changes persistent?

2. What command did you use to perform an orderly shutdown?

3. What changes to SELinux settings should you verify?