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 6.
If you've run the exercises while reading the chapter, it's best to use a different virtual machine. If one is not available, the first thing you should do is delete any logical volumes, volume groups, and physical volumes created during the chapter. To that end, the lvremove, vgremove, and pvremove commands should prove helpful.
Next, delete the partitions created during the chapter. If you used the spare hard drives created for the virtual machines specified in Chapter 2, those would be in the /dev/sda and /dev/sdb hard drive device files.
Lab 1
This lab assumes you have a new hard disk (or at least empty space on a current hard drive where you can add a new partition). You can simulate a new hard disk by adding appropriate settings to a KVM or VMware virtual machine. In this lab, you'll create one new partition using parted, format it to the ext4 filesystem, and configure it on the /test1 directory in /etc/fstab so that the new partition is properly mounted the next time you boot Linux. You'll also create a second new partition using fdisk, format it, and configure as additional swap space /etc/fstab so that space is also used the next time you boot Linux. Oh yes, use the UUIDs in /etc/fstab.
Lab 2
In this lab, you'll set up a formatted logical volume, based on partitions appropriately configured. If you use the partitions created in Lab 1, don't forget to delete or at least comment out any associated settings in the /etc/fstab file.
Once you create a VG, don't use it all. For example, if you've set up a VG of 1000MB, configure 900 MB as a LV. Mount the resulting logical volume on the /test2 directory, and confirm the result with the mount and df commands. Name the VG volgroup1 and the LV logvol1.
Set it up on the /test2 directory in the /etc/fstab file, formatted to the ext4 filesystem. Use the UUID for the associated logical volume device in /etc/fstab.
Lab 3
In this lab, you'll continue the work done in Lab 2, expanding the space available to the formatted LV closer to the capacity of the VG. For example, if you were able to follow the size guidelines in Lab 2, use appropriate commands to increase the space available to the LV from 900MB to 950MB. Set it up on the /test3 directory in the /etc/fstab file, formatted to the ext4 filesystem. Use the UUID for the associated logical volume device in /etc/fstab.
Don't forget to delete or at least comment out any settings from previous labs in the /etc/fstab file. Just one hint: it's far too easy to skip steps during the process.
Lab 4
In this lab, you'll set up a filesystem formatted with LUKS encryption. It's appropriate to use either the partition created in Lab 1 or the logical volume created in Lab 2. In fact, it would be helpful to practice creating such encryption in both ways.
Of course, there are risks with any sort of encryption, especially if the passphrase is lost. For the purpose of this lab, write down the passphrase you choose! There is no requirement to first prepare the filesystem with random data. Confirm the result.
Lab 5
In this lab, you'll set up the LUKS-encrypted volume set up in Lab 4 in the /etc/fstab configuration file. Try it with the /dev/mapper device file, as well as the associated UUID. Be sure to select the correct UUID.
Lab 6
In this lab, you'll configure the automounter to automatically read an installed CD/DVD. While NFS services are covered in Chapter 17, the Red Hat RHCSA prep course does suggest that you need to know how to use the automounter to connect to a shared NFS directory. So the steps included in this lab are designed to help you set up a simple shared NFS directory on one system, with connections allowed from a second system. If you've set up the systems described in Chapter 2, the first system would be server1.example.com, and the second system would be tester1.example.com. If you're using RHEL 6, it assumes that you have a connection to the Red Hat Network. If you're using a rebuild distribution such as Scientific Linux 6, it assumes you have a connection to the standard repositories for that distribution as discussed in Chapter 7. You should not need to read that chapter. As long as networking is configured and connected to the Internet as discussed in Chapter 3, a connection to such repositories is enabled by default.
1. On the first system, back up your current /etc/auto.master and /etc/auto.net configuration files.
2. Install NFS server configuration files with the following command:
# yum install nfs-utils
3. If you're working with the baseline virtual system configured in Chapter 2, this NFS and related packages should already be installed.
4. Share the /tmp directory by adding the following line to /etc/exports. Be careful; don't include extra spaces:
/tmp *(ro)
5. Activate the NFS service, and disable any current iptables-based firewall with the following commands. (Firewalls are described in Chapter 4.)
#
/etc/init.d/nfs restart
# iptables -F
Bonus: it's best if you can use the Firewall Configuration tool or iptables commands to support access through a firewall, as it is a RHCSA skill.
6. Record the IP address of the local system, as shown by the ifconfig command. If it's the server1.example.com system described in Chapter 2, it should be 192.168.122.50; but another IP address is OK okay too.
7. Go to another RHEL 6 system, such as the tester1.example.com system described in Chapter 2. The following command should confirm a good connection to the remote NFS server; substitute the IP address of the remote system for remote_ipaddr.
# showmount -e remote_ipaddr
8. Now you can configure the local automounter for both a connection to a CD/DVD and a shared NFS directory, using the techniques described in the chapter.