1. Aruba Validated Solution Guide: Data Center Interconnect with Aruba CX Switches (April 2021). This guide explicitly details the architecture described in the question.
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"Layer 2 DCI" section: "A simple solution for campus data centers is to extend the L2 domains between the two locations. This can be achieved by creating a VSX LAG between the pairs of VSX switches." The guide includes a diagram (Figure 3) illustrating this exact topology
labeling it as "VSX LAG for L2 DCI."
2. ArubaOS-CX VSX Configuration Guide for CX 10.12 (Part Number: 5200-8318a
Edition: 1). This official vendor documentation describes the capabilities of VSX LAGs.
Chapter: "VSX LAGs
" Section: "Interconnecting two VSX pairs with a VSX LAG": This section states
"A VSX LAG can be configured between two different VSX pairs. This configuration is useful in a data center environment where a pair of VSX switches are in one rack and another pair of VSX switches are in another rack." This confirms that the fundamental technology for connecting two separate VSX clusters via a VSX LAG is a supported feature.