Changes

{{Admon/caution|Draft LabTHIS IS AN OLD VERSION OF THE LAB|'''This lab has NOT been released for regular distributionis an archived version. When the lab is ready to be released, Do not use this caution banner will disappearin your OPS235 course.'''}}

{{Admon/note | Use the f17host c6host | Complete the following steps on your '''f17hostc6host''' computer system.}}

# On Turn off your '''f17host''' machine start virtual machines# Start Virtual Machine Manager

<li value="15">Now we need to add reconfigure our 3 VMs to use our new virtual network '''network1''' to the 3 VM's

<li value="1">Select the '''fedora1centos1''' VM and edit the '''Virtual Machine Details'''<br />(Note: the Virtual Machine window will appear - do not start virtual machine)</li>

<li>Click on the '''Remove''' button at the bottom right-side of the dialog box.</li> <li>Click on '''Add Hardware''' on the bottom left-side of the dialog box and add a new network</li> <li>For the host device, locate and select Change it to '''Virtual Network network1''' : NAT</li> <li>Click finish to exit the Virtual Machine Details dialog box.</li>

{{Admon/note | Use fedora2 centos2 | Complete this investigation on your fedora2 centos2 VM.}}# Start '''fedora2centos2''' VM and login# On your '''fedora centos host''' run <code>ifconfig</code> and make note of the IP address assigned to the <code>virbr1</code> interface. This will be your the default gateway and DNS server for your Vm'sVMs.[[Image:new_network_dialog.png|thumb|350px]]# Make certain to return to your fedora2 VM.# To configure a new interface on fedora2 go to '''Applications'''->'''Other'''->'''Network Connections'''.# Make certain there are no '''"Wired"''' connections (even if you have to click on Edit the connection name and click the '''Delete''' button.# Create a new existing wired connection, with the "Connection Name" at the top to read '''eth1'''# Click on the '''Add''' button, and select In the '''IPv4 Settings''' tab.# Change change the method from "Automatic (DHCP)" to '''"Manual"'''.

#: Default Gateway '''192.168.235.1''' (The IP address of <code>virbr1</code> on your fedora centos host.)# Click on the '''DNS''' field and add '''192The IP address of <code>virbr1</code> on your centos host.168.235.1''' as the primary DNS server.# Click '''Save''' to Finish, and exit the Network Connections dialog box.# Your network connection may take a couple of minutes to reconfigure connect (view the Network Manager applet in the gnome panel at the top of the screen). If there is no connection after a few minutes, you should be able to right-click on the applet and click "eth1" to connect.# You should be able to use the systemctl command service commands to restart your network.#'''Restart your network''' on fedora2 by issuing the commands:#*<code>systemctl service network stop NetworkManager.service</code>#*<code>systemctl service network start NetworkManager.service</code>

# To verify that fedora2 centos2 has the correct default gateway configured, enter use the command: commands <code>route -n</code># Verify the network by using: , <code>ifconfig</code>, <code>nslookup</code>, and <code>ping 192.168.235.1</code>

{{Admon/note | Use fedora1 centos1 | Complete this investigation on your fedora1 centos1 VM.}}

# Start the '''fedora1centos1''' VM and login# Before we configure fedora1 centos1 we should create a timestamp file that can be used to see which files have changed as a result of using the GUI tool.

# Run the network configuration tool and enter the following static configuration in the same way that you configured '''fedora2centos2'''.

# Restart You may have to restart the NetworkManager servicenetwork using the correct command.# Verify the configuration by pinging fedora centos host ('''192.168.235.1''') and fedora2 centos2 ('''192.168.235.12''')# To verify that fedora1 has the correct default gateway configured, enter the command <code>route -n</code>

Previously, you created a file called <code>/tmp/timestamp</code> that just contains the current date and time prior to running the network configuration toool for fedora2.centos1. Any files that were modified by the GUI network configuration program should have a timestamp later (or newer) than the "timestamp" file you created. All the Linux TCP/IP configuration files are stored under the '''/etc''' directory or its sub-directories. The <code>find</code> command (using the correct options) can be used to only list those files that have been recently created since the timestamp date contained in the <code>/tmp/timestamp</code> file.|}}

{{Admon/note | Use fedora3 centos3 | Complete this investigation on your fedora3 centos3 VM.}}# Start '''fedora3centos3''' VM and login as root

#* <code>ping</code> your other VM's and fedora centos host.

# Restart the <code>fedora3centos3</code> VM, or just wait a few minutes.

#* Change to the <code>/etc/sysconfig/network-scripts</code> directory on <code>fedora3</code>

#* look Look for the config file for your original interface, it should be named <code>ifcfg-eth0</code>#* Copy that Make a backup of this file to <code>ifcfg-eth<b>N</b></code> where <b>N</b> relates to your current eth interface number (we will use <b>eth1</b> as an example)for later reference.#* Edit the new file for you interface and give it the following settings(or create a brand new file, might be easier than editing the old one):#**DEVICE="eth1eth0" <-- '''or the interface name YOU have '''

#**HWADDR="52:54:00:3f:5c:fa" <-- '''use the HWADDR MAC address for YOUR interface

# Save the file and then restart the network connection by issuing the commands: <code>ifdown eth1</code> and then <code>ifup eth1</code><br /><br ><b>NOTE: </b>If there are errors, check that the hardware address in the config file matches the hardware address of the device its configuring<br /><br />

# Finally the kickstart file used to install this VM did not set the hostname. Edit the file <code>/etc/sysconfig/network</code> and set the hostname to <code>fedora3</code># Restart the <code>fedora3centos3</code> VM.

{{Admon/note | Use each machine | Complete this investigation on all of your VM's and the Fedora centos host.}}

{{Admon/note | Hosts files vs. the Domain Name System | On large public networks like the Internet or even large private networks we use a network service called [http://en.wikipedia.org/wiki/Domain_Name_System Domain Name System (DNS)] to resolve the human friendly hostnames like '''fedoraprojectcentos.org''' to the numeric addresses used by the IP protocol. On smaller networks we can use the <code>/etc/hosts</code> on each system to resolve names to addresses.}}

# Use the <code>hostname</code> and <code>ifconfig</code> commands on your fedora centos host and all 3 VM's to gather the information needed to configure the <code>/etc/hosts</code> file on the fedora centos host and the 3 VM's.# Edit the <code>/etc/hosts</code> file on <u>each</u> of the '''virtual machines and the fedora centos host'''. Refer to the table below for information to enter in the <code>/etc/hosts</code> file.

# hostname fedora1 centos1 added to /etc/hosts by anaconda127.0.0.1 localhost.localdomain localhost fedora1centos1::1 localhost6.localdomain6 localhost6 fedora1centos1

192.168.235.1 f17hostc6host192.168.235.11 fedora1centos1192.168.235.12 fedora2centos2192.168.235.13 fedora3centos3

{{Admon/note | Use your Fedora CentOS Host | Complete this investigation on your Fedora CentOS host.}}

{{Admon/note | Obtaining Remote MAC Addresses| The term '''MAC''' address stands for '''Media Access Control''' address, which provides a unique ID to prevent confusion among computer systems within a network. While we use '''32bit IP addresse'''s to communicate over an internetworkinternet, on the local ethernet network packets are delivered to a '''48bit hardware address''' (sometimes called a MAC address). The '''ARP''' protocol resolves 32bit IP addresses to 48bit MAC addresses by using a broadcast and caching the results. We can examine the ARP cache to get the MAC addresses of other computers on our local network.<br /><br />Being able to determine remote MAC address information is useful from troubleshooting networking programs to using '''WOL''' (Wake up on Lan) to automatically boot remote workstations via the network. In this investigation, you will learn how to obtain MAC address information for various network cards.}}

# On the fedora centos host <code>ping</code> each of your VM's

# What was the difference in output? For what other command did -n have a similar effect?

=== Investigation 7: How can I see what network services or ports are active {{Admon/note | Use All Machines | Complete this investigation on my Fedora system? ===all of your VM's and the CentOS host.}}

{{Admon/note | Use Network Ports | When our CentOS system provides any services on a network, those services are accessible through a port number. All Machines | Complete this investigation network services are configured to be accessed on a particular port number. By examining which ports are active on all our system we can know what services (and points of your VM's attack) are available on our system. The ability to examine this information is important for troubleshooting network services and securing our systems. One great tool for this is the Fedora host<code>netstat</code> command.}}

{{Admon/note | Network Ports | When our Fedora system provides any services on a network, those services are accessible through a port number. All network services are configured to be accessed on a particular port number. By examining which ports are active on our system we can know what services (and points of attack) are available on our system. The ability to examine this information is important for troubleshooting network services and securing our systems. One great tool for this is the <code>netstat</code> command.}} # On your fedora CentOS host execute the command: <code>netstat -at</code>

# On the fedora CentOS host rerun the command and in addition to the LISTEN port it should list a 2nd entry with a state of ESTABLISHED. This shows that there is a current connection to your ssh server.# Exit your ssh connection from the VM and rerun the command on the fedora CentOS host. Instead of ESTABLISHED it should now show a state of CLOSE_WAIT. Indicating that the TCP connection is being closed.# On your fedora CentOS host try the command <code>netstat -atn</code>. How is this output different?

{{Admon/note | Use the f17host c6host | Complete the following steps on your '''f17hostc6host''' computer systemmachine.}}

{{Admon/note | | [http://en.wikipedia.org/wiki/Iptables Iptables] is the built-in firewall for LINUX. While this program can be controlled by different GUI'sGUIs, we are going to investigate the powerful command line interface for this program to choose what data is allowed into, out of and through our computer.

# As root on the fedora CentOS host enter the following commands at the prompt:

# Now insert a rule on the fedora CentOS host that would ACCEPT connections from the fedora2 centos2 VM only.

<li>Write a short bash script to add a rule allowing the fedora1 centos1 and fedora3 centos3 VM's to connect to <code>ssh</code> on the fedora CentOS host.</li>

[[Image:new-network-config2config.png]] * '''Fedora host''' has 1 active network interface (probably <code>'''em1'''</code>)that receives IP configuration from the School's DHCP server.* '''Fedora host''' has 1 active network interface (<code>'''virbr1'''</code>) that has a static default configuration of '''192.168.235.1/255.255.255.0'''* '''Fedora1''' VM has 1 active interface (<code>'''eth1'''</code>) that has a static configuration of '''192.168.235.11/255.255.255.0'''* '''Fedora2''' VM has 1 active interface (<code>'''eth1'''</code>) that has a static configuration of '''192.168.235.12/255.255.255.0'''* '''Fedora3''' VM has 1 active interface (<code>'''eth1'''</code>) that has a static configuration of '''192.168.235.13/255.255.255.0'''

# A list <code>ifconfig</code> from all 3 VM's# The contents of your <code>iptables/etc/hosts</code> rules.on each machine

# <code>ssh</code> from fedora2 centos2 to fedora the CentOS host.# <code>ifconfig</code> from all 3 VM's