Question 6 - HPE7-A01 discussion

The correct answers are A and D.

According to the web search results, VSX LAG is a feature that allows multiple PSKs to be used on a single SSID, providing device-specific or group-specific passphrases for enhanced security and deployment flexibility for headless IoT devices1. VSX LAGs span both aggregation switches and appear as one device to partner downstream or upstream devices or both when forming a LAG with the VSX pair2.

One of the statements that is true about VSX LAG is that the total number of configured links may not exceed 8 for the pair or 4 per switch1. This means that a VSX LAG across a downstream switch can have at most a total of eight member links, and a switch can have a maximum of four member links. When creating a VSX LAG, it is recommended to select an equal number of member links in each segment for load balancing1.

Another statement that is true about VSX LAG is that outgoing traffic is preferentially switched to local members of the LAG2. This means that when active forwarding and active gateway are enabled, north-south and south-north traffic bypasses the ISL link and uses the local ports on the switch. This optimizes the traffic path and reduces the load on the ISL link2.

The other statements are false or not relevant for VSX LAG. Outgoing traffic is not switched to a port based on a hashing algorithm, which may be either switch in the pair. This is a characteristic of MLAG (Multi-Chassis Link Aggregation), which is a different feature from VSX LAG. LAG traffic is not passed over VSX ISL links only while upgrading firmware on the switch pair. This is a scenario that may occur when performing hitless upgrades, which is a feature that allows software updates without impacting network availability. The number of VSX lags that can be configured on all 83xx and 84xx model switches is not 255, but depends on the switch model and firmware version. For example, the AOS-CX 10.04 supports up to 64 VSX lags for 8320 switches and up to 128 VSX lags for 8325 and 8400 switches.