Hands-On Lab
215
2.
The t will keep the ping running. Go to the 1900 switch and perform
a shut and no shut on int e0/4, then notice how long it takes before
the pings resume. This could be up to 50 seconds (although, if you
have a small network, it may resume faster).
3.
Leave the pings running. Go to int e0/4 and type spantree start-
forwarding
, which turns on PortFast for that port.
4.
Go to the 1900 switch and perform a shut, then a no shut on e0/4.
The pings will time out but should resume after only a few seconds.
5.
Leave the Ping program running. Type show spantree 1 and notice
which port is forwarding and which port is blocking.
6.
Leave the Ping program running. Perform a shutdown on the forward-
ing interface. Notice that the pings have timed out, but they should
resume after a few seconds.
7.
Type show spantree 1 and notice which port is forwarding.
8.
Perform a no shutdown on the port you originally shut down. Notice
that the pings have timed out again, but the pings should resume after
a few moments.
9.
Turn on UplinkFast on your 1900 forwarding port by typing uplink-
fast
from global configuration mode.
10.
Perform steps 5 through 8 again and notice that the ping's time-out
and resume cycle was shorter. UplinkFast demonstrated an almost
immediate transition to the second trunk link when the forwarding
link was shut down.
11.
Configure the 5000 series switch as the STP root switch by typing set
spantree root 1-4 dia 2
from the enable mode of the switch. The
diameter of the network is determined by counting the switches con-
nected to the root, including the root, which in this case is 2. The
VLANs configured are 14.
12.
Verify the configuration by typing show spantree 1. Notice the root
designation.
13.
Make sure your links are trunked by typing show trunk on the 5000
series switch.
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