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You issue the port-channel load-balance dst-port module 4 command on a Cisco Nexus 7000 Series switch running

You issue the port-channel load-balance dst-port module 4 command on a Cisco Nexus 7000 Series switch running NX-OS 6.2.
How is distribution loaded for port channels on slot 4?

A. based on the source port
B. based on the source IP address and destination port
C. based on the source MAC address and destination port only
D. based on the defaults because the command contains invalid syntax

E. based on the destination port

Explanation:

Distribution for port channels on slot 4 in this scenario is loaded based on the destination port because the command has been issued with the dst-port keyword and the module 4 keyword. The port-channel load-balance command can be used to modify the load distribution criteria used by EtherChannel. The basic syntax of the port-channel load-balance command is port-channel load-balance method [module slot], where method os one of the following 10 keywords:
• dst-ip
• dst-mac
• dst-port
• scr-dst-ip
• scr-dst-mac
• scr-dst-port
• scr-ip
• scr-mac
• scr-port
• vlan-only
The dst-ip keyword, dst-mac keyword, and dst-port keyword load port channel distribution based on the destination Internet Protocol (IP) address, Media Access Control (MAC) address, and port number, respectively. Similarly, the scr-ip keyword, scr-mac keyword, and scr-port keyword load port channel distribution based on the source IP address, source MAC address, and port number, respectively. The scr-dst-ip keyword, scr-dst-mac keyword, and scr-dst-port keyword load port channel distribution based on the source and destination IP addresses, MAC addresses, and port numbers, respectively. The vlan-only keyword loads distribution on only virtual local area network (VLAN) modules.
The optional module keyword accepts a slot number value. If you configure the port-channel load-balance command with the module keyword, the configuration applies only to the specified slot. Otherwise, the configuration applies to the entire device. By default, on a Cisco Nexus switch, a port channel load balances Layer 2 packets based on the source and destination MAC addresses. Layer 3 packets, on the other hand, are load balanced based on the source and destination IP addresses. You must be operating in the default virtual device context (VDC) on the switch in order to issue the port-channel load-balance command.
The command in this scenario does not contain invalid syntax, because the Nexus switch in this scenario is running NX-OS 6.2. Prior to NX-OS 5.1(3), the port-channel load-balanced command required an ethernet keyword. Therefore, the valid syntax for NX-OS versions older than 5.1(3) is port-channel load-balance ethernet method [module slot]. In NX-OS 5.1(3), Cisco removed that keyword.

Reference:

Cisco: Cisco Nexus 7000 Series NX-OS Interfaces Command Reference: port-channel load-balance


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