I also ran ibdiagnet -pc -lw 4x -ls 25 -P all=1 --pm_pause_time 600 --get_cable_infoon all the four servers. All resulted
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Summary
-I- Stage Warnings Errors Comment
-I- Discovery 0 0
-I- Lids Check 0 0
-I- Links Check 0 0
-I- Subnet Manager 0 0
-I- Port Counters 0 0
-I- Nodes Information 0 0
-I- Speed / Width checks 0 0
-I- Partition Keys 0 0
-I- Alias GUIDs 0 0
-I- Temperature Sensing 0 0
-I- Cable Diagnostic (Plugin) 0 0