Cisco 2511 - Router - EN Instrukcja Użytkownika Pobierz pdf (Strona 22)

Notice the success rate is 100 % meaning you successfully reached the

destination router. Congratulations! If you have anything below 100% the

router has difficulty with making a network connection to the other router.

Finding the Point of Failure – traceroute

The traceroute command is used to find the actual path that packets took to

reach its destination. Instead of testing just end-to-end connectivity, as ping,

traceroute is used to check each link along the packet route.

Experiment with the traceroute command as we did with ping, starting with

the line command:

r1# traceroute IP address of destination

The trace command terminates when the destination responds, when the

maximum TTL is exceeded, or when the user interrupts the trace with the

escape sequence. To invoke the escape sequence, simultaneously press and

release the Ctrl, Shift, and 6 keys, and then press the X key.

8. Investigating the Hold Timers

EXERCISE 9: Viewing the Hold Timers____________________________

Hold timers specify the amount of time a receiving device should hold the

information sent by your device before discarding it. The default time

value for hold timers is 180 seconds. Let’s see how this works. While

connected to r1 change the hostname to a different router name.

Then telnet to r3, and enter:

r3# sh cdp neighbors

Repeat the sh cdp neighbors command for a few times as the hold timers

count down from 180 seconds. Notice that almost immediately the router

detects the new hostname and updates it in the cdp neighboring table. Also

notice that after 180 seconds time period elapses the old hostname for the

router was flushed out of the cdp neighbor table. Your results should be

similar to the ones as shown in the following window:

1 2 ... 17 18 19 20 21 22 23 24

Brak uwag

Cisco 2511 - Router - EN Instrukcja Użytkownika Strona 22