Configure Trunks on S$1,$ S$2,$ and S$3.$

Dynamic trunking protocol $($DTP$)$ manages the trunk links between Cisco switches. Currently, all the switchports are in the default trunking mode, which is dynamic auto. In this step, you will change the trunking mode to dynamic desirable for the link between switches S$1$ and S$2.$ The link between switches S$1$ and S$3$ will be set as a static trunk. Use VLAN $999$ as the native VLAN in this topology.

a$.$ On switch S$1,$ configure the trunk link to dynamic desirable on the GigabitEthernet $0/1$ interface. The configuration of S$1$ is shown below.

S$1($config$)$# interface g$0/1$

S$1($config$-$if$)$# switchport mode dynamic desirable

Question:

What will be the result of trunk negotiation between S$1$ and S$2?\_$In Trucking Operation$\_\_\_\_\_\_\_\_\_\_\_$

Type your answers here.

b$.$ On switch S$2,$ verify that the trunk has been negotiated by entering the show interfaces trunk command.

Interface GigabitEthernet $0/1$ should appear in the output.

Question:

What is the mode and status for this port? $\_\_$Mode $$ Auto, Status$-$ Trunking$\_\_\_\_\_\_\_\_\_\_\_$

Type your answers here.

c$.$ For the trunk link between S$1$ and S$3,$ configure interface GigabitEthernet $0/2$ as a static trunk link on S$1.$ In addition, disable DTP negotiation on interface G$0/2$ on S$1.$

S$1($config$)$# interface g$0/2$

S$1($config$-$if$)$# switchport mode trunk

S$1($config$-$if$)$# switchport nonegotiate

d$.$ Use the show dtp command to verify the status of DTP$.$

S$1$# show dtp

Global DTP information

Sending DTP Hello packets every $30$ seconds

Dynamic Trunk timeout is $300$ seconds

$1$ interfaces using DTP

e$.$ Verify trunking is enabled on all the switches using the show interfaces trunk command.

S$1$# show interfaces trunk

Port Mode Encapsulation Status Native vlan

Gig$0/1$ desirable n$-802\mathrm{.}1$q trunking $1$

Gig$0/2$ on $802\mathrm{.}1$q trunking $1$

Port Vlans allowed on trunk

Gig$0/11-1005$

Gig$0/21-1005$

Port Vlans allowed and active in management domain

Gig$0/11,99,999$

Gig$0/21,99,999$

Port Vlans in spanning tree forwarding state and not pruned

Gig$0/11,99,999$

Gig$0/21,99,999$

Question:

What is the native VLAN for these trunks currently? $\_\_$VLAN $1\_\_\_\_\_\_\_\_\_\_\_\_$

Type your answers here.

f$.$ Configure VLAN $999$ as the native VLAN for the trunk links on S$1.$

S$1($config$)$# interface range g$0/1-2$

S$1($config$-$if$-$range$)$# switchport trunk native vlan $999$

Question:

What messages did you receive on S$1?$ How would you correct it$?$ GigabitEthernet $0/1$ is blocked on VLAN$999$ due to Inconsistent local Vlan.