300-410 ENARSI: Implementing Cisco Enterprise Advanced Routing and ServicesDemo

Question

An administrator tries to download the .pack NBAR2 file with TFTP from the CPE router to another device through the Gi0/0 interface. The CPE has the following configuration:

hostname CPE  
!  
ip access-list extended WAN  
&lt;`¦&gt;  
remark =&gt; All UDP rules below for WAN ID: S421T18E58F90  
permit udp any eq domain any  
permit udp any any eq tftp  
deny udp any any  
!  
interface GigabitEthernet0/0  
&lt;`¦&gt;  
ip access-group WAN in  
&lt;`¦&gt;  
!  
tftp-server flash:pp-adv-csr1000v-1612.1a-37-53.0.0.pack

The transfer fails. What action resolves the issue?

A Make the permit udp any eq tftp any entry the last entry in the WAN ACL
B Shorten the file name to the 8+3 naming convention
C Change the WAN ACL to permit the entire UDP destination port range
D Change the WAN ACL to permit the UDP port 69 to allow TFTP

Explanation

TFTP sends its initial request to UDP port 69, but the file-transfer session subsequently uses dynamically assigned UDP ports. An ACL that allows only destination port 69 and then denies all UDP blocks the negotiated data traffic; allowing the full UDP destination-port range permits the transfer.

Learn more

Cisco: ACLs on WLCs — Rules, Limitations, and Examples

300-410 ENARSI: Implementing Cisco Enterprise Advanced Routing and ServicesDemo

AstroTutor

Notes

Readiness

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