An administrator is defining a VSX LAG on a pair of AOS-CX switches that are defined as primary and secondary. The VSX LAG fails to establish successfully with a remote switch; however, after verification, the remote switch is configured correctly. The administrator narrows down the problem to the configuration on the
AOS-CX switches.
What would cause this problem?
The problem is likely caused by the VSX LAG interfaces being in layer-3 mode. In Aruba AOS-CX switches, VSX LAGs are only supported in layer-2 mode. If the interfaces are configured in layer-3 mode, it would prevent the VSX LAG from being established correctly with the remote switch. Ensuring that the interfaces are set to layer-2 mode should resolve the issue.
Answer should be C - VSX LAG are not supported at Layer 3 VSX LAG does support all the standard LAG adjustments: timers, L2 or L3 hashing, LACP fallback. It supports both LACP mode active or static mode, and only Layer 2 (i.e. no routed mode).
I think it's B, because, as the question is exposed, i understand that the VSX LAG has been configured, but fails to establish. If interfaces where in Layer 3 mode, you will not be able to configure them as a LAG.
try accessing the device from lab then you will find you are wrong, and hash is not something manual configured, so not a possible human error, this question is asking for trouble shooting skills.
Switches can bring up VSX LAG with differently defined hashes, its not B IMO.
Page 215 Study Guide: VSX LAGs are layer 2 only, [Aruba Networks]
I think B is correct. check the following link. https://www.arubanetworks.com/techdocs/AOS-CX/AOSCX-CLI-Bank/cli_6200/Content/VSX_cmds/sho-lac-agg-10.htm
I think C is the good answer. VSX LAG are not supported at Layer 3
I think D is correct.
Why do you think it is correct?
B is correct.
Pretty sure that switches do not negotiate the lag hash algorithm in the handshake. Cannot be B. I vote for C.
B: Verify that the LAG hash settings match on both the local and remote VSX peers.
In Aruba's Virtual Switching Extension (VSX) technology, the LAG interfaces can be configured in both Layer 2 and Layer 3 modes, depending on the specific requirements of your network design
This document says NO layer 3 interfaces for VSX LAG: https://www.arubanetworks.com/techdocs/AOS-CX/10.10/HTML/vsx/Content/Chp_Start/vsx-sol-req-10.htm Answer: C