Recitation 5 (R5)

CT 320: Network and Systems Administration
Group Project

Network Setup Lab

The purpose of this assignment is to experiment with the setup of networking and network-based programs. This lab will be documented in Assignment 5.

Part 1 – Setup Networking

NOTE: This lab requires you to have root privileges throughout!

Make sure that the system host name is ct320x with domain name ct320.net. The TA will allocate host names from ct3200 to ct3208.

    # hostname ct320x

Turn off and disable the Network Manager as follows:

    # service NetworkManager stop
    # chkconfig NetworkManager off

Edit /etc/sysconfig/network-script/ifcfg-em1 as follows:

    UUID="<uuid>"
    HWADDR="<macid>"
    NM_CONTROLLED=no
    BOOTPROTO=none
    DEVICE=em1
    ONBOOT=yes
    IPADDR=10.1.1.4x // where x is the last digit of ct320x
    NETMASK=255.255.255.0
    GATEWAY=10.1.1.1
    IPV6INIT=no

Edit /etc/resolv.conf to add a single name server:

    nameserver 129.82.45.181

You will have to use IP addresses throughout the rest of this lab instead of host names, see Part 6 for an explanation.

Part 2 – Test Networking

Make sure you can access the Internet and Domain Name Service (DNS) by typing the commands shown below.

    # dig www.google.com
    # yum search dhcp

If the dig command returns a valid address, and the yum search works, bring up the Firefox browser to use for the remainder of the lab. Otherwise troubleshoot the problem with the help of the TA.

Part 3 – Network File System (NFS)

Install the NFS related packages, which you can find be searching with yum.

SERVER

Create a directory with the path name /export and populate it with several directories and files. Figure out how to export the file system by adding an entry to /etc/exports, and add an entry to /etc/hosts.allow for your neighbor’s system. Make sure that the appropriate daemons are running and document their names. Now restart the NFS service and verify that your neighbors can access the exported file system. Remove the entry from /etc/hosts.allow and add an entry to /etc/hosts.deny. Restart the NFS service and verify that your neighbor cannot mount the driver, then restore access.

CLIENT

Create a directory with the path name /import and use the mount command below to mount /export from their system to yours:

    # mount 10.1.1.4x:/export /import

Make sure you can browse the imported file system. Now add an entry to /etc/fstab to automate the mounting of your neighbor’s exported file system. Reboot and verify that you still have access to their files. At this point you should be able to access your neighbor’s exported file system and they should be able access to yours.

Part 4 – Secure Shell (SSH)

Make sure that the sshd daemon is running. Use the ssh command to gain access to the ct320 account on your neighbor system and have them do the same. Use the scp command to copy files between the systems. Is this equivalent functionality to the NFS exercise in Part 3? What are the advantages or disadvantages or each method. How can you control ssh access, without disabling the sshd daemon?

Part 5 – Dynamic Host Configuration Protocol (DHCP)

This is a group exercise for the entire recitation. Install the DHCP server on one system in the lab using yum. Bring up the DHCP server on this system by editing the associated configuration file. Now reenable the Network Manager and use it to convertall other systems to dynamic addressing. Change the Network Manager setting to DHCP (and remove the static IP address). See if the system will automatically get a DHCP assigned IP address. Find where DHCP server messages are logged and examine it. Make sure that you get a copy of the DHCP configuration file for your report. What other information can be transmitted to clients by the DHCP server? Please restore the systems to their original static IP address and disable the DHCP server after completing this exercise. Make sure that your system has Internet connectivity before leaving.

Part 6 – Extra Credit

The department name servers do not know about the systems in the lab, and therefore cannot map host names to IP address for these systems. Extra credit will be given to students that figure out how to enable use of host names instead of IP addresses. You must explain your methodology and show the TA that host names are working to get extra points!

Part 7 – Checkin

The checkin for this recitation will be added to Assignment 5, so save your notes and documents from the lab. There will not be a drop box on RamCT for this recitation.