Computing 205/406 & IT8

Tutorial #15

1. What information can the network manager obtain from the ping command? What does ping actually do?

2. What does the traceroute command do? How does it do it?

3. In the lecture, it was claimed that the OBJECT IDENTIFIERS

   { 1 3 6 1 }, and
   { internet }
   

   were equivalent (ie: referred to the same object). How is this?

4. The following are some (highly edited) entries from the standard Unix MIB definition, in file /etc/mib.txt.

   ipForwarding OBJECT-TYPE ::= { ip 1 }
   icmpInEchos OBJECT-TYPE ::= { icmp 8 }
   tcpMaxConn OBJECT-TYPE ::= { tcp 4 }
   

   What are the numeric OBJECT IDENTIFIERS of the objects ipForwarding, icmpInEchoes and tcpMaxConn.

5. Marshall T. Rose[1] espouses the fundamental axiom of network management, which is: The impact of adding management to managed nodes must be minimal, reflecting a lowest common denominator Discuss.

Practical Exercises:

• Use the ping[2] command to check reachability of various hosts at Bendigo and elsewhere. Now investigate the command line options of ping. Be sure to to try it on both the Indys and redgum.

• The traceroute command is available on redgum. Use traceroute (judiciously - see the man page). Now have a look at ntping on the SGI systems (Indys, ironbark).