Online Access Free 640-821 Practice Test
| Exam Code: | 640-821 |
| Exam Name: | Introduction to Cisco Networking Technologies |
| Certification Provider: | Cisco |
| Free Question Number: | 91 |
| Posted: | Oct 12, 2026 |
The routers in the diagram are being used to prototype a WAN. The two routers are interconnected with back-to-back cables between their serial interfaces. How should the serial interface of the Test1 router be configured to establish Layer 3 connectivity between the two routers?
Refer to the exhibit. A person is trying to send a file from a host on Network A of the JAX
Company to a server on Network Z of the XYZ Company. The file transfer fails. The host on Network A can communicate with other hosts on Network A.
Which command, issued
from router RTA, would be the most useful for troubleshooting this problem?

