Difference between revisions of "NAD710 Lab 2 Answers"

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To re-enable ARP on a network interface named 'ethxxx', one would use a command of the form 'ifconfig ethxxx arp'.
 
To re-enable ARP on a network interface named 'ethxxx', one would use a command of the form 'ifconfig ethxxx arp'.
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'''4. What is the consequence of disabling ARP on a network interface?'''
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Answer:
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If ARP has been disabled on a network interface, ARP packets recieved by that interface will be dropped. This prevents the machine from either resolving the corresponding MAC address for a particular IP address or from responding to a requestion for such resolution.

Revision as of 16:48, 11 September 2008

1. What is the effect of the first "ifconfig ethxx down" command on the system's ARP cache ?

Answer:

The arp table becomes empty after the first "ifconfig eth1 down"

[root@localhost ~]# arp -n
Address                  HWtype  HWaddress           Flags Mask    Iface
142.204.141.131          ether   00:0E:7F:3C:A8:F3   C             eth1
142.204.141.129          ether   00:0E:0C:4B:31:5C   C             eth1
[root@localhost ~]# ifconfig eth1 down
[root@localhost ~]# arp -n
[root@localhost ~]# ifconfig eth1 up
[root@localhost ~]# arp -n

2. What command disable ARP on a network interface?

Answer:

To disable ARP on a network interface named 'ethxxx', one would use a command of the form 'ifconfing ethxxx -arp'.


3. How do you enable ARP on a network interface if it has been disabled?

Answer:

To re-enable ARP on a network interface named 'ethxxx', one would use a command of the form 'ifconfig ethxxx arp'.

4. What is the consequence of disabling ARP on a network interface?

Answer:

If ARP has been disabled on a network interface, ARP packets recieved by that interface will be dropped. This prevents the machine from either resolving the corresponding MAC address for a particular IP address or from responding to a requestion for such resolution.