We did try resetting the iDracs, and that didn't do it for us. Eventually we did get the issue resolved with the help of support. They updated the version of the Dell PTAgent running on the hosts from 1.7-1 to 1.7-4, and restarted that service. Once that was done, all the appliances showed up in VXRail manager again, and I was able to upgrade the whole cluster version to 4.5.211. Since then I haven't seen the problem again.
Hello,  I am wondering if anyone has seen this issue before. I am working with a cluster of 5 VxRail E460F nodes, and the manager VM seems to lose contact with the nodes, or with components in them. This is not specific to one node, it seems to randomly change. Sometimes the health page will show all nodes connected, sometimes one or many appear as missing. Sometimes the node shows connected, but disks show offline.   From vCenter, I see no issues. All the hosts are present, and VSAN is functioning properly.   Another thing to mention, occasionally I see the status LEDs on the drives in the appliances themselves are not lit. The activity LEDs light, but the status LED does not even though the drives are attached and working.  Things I have done so far: Reset iDracs Upgraded iDrac firmware to latest version Restarted VxRail Manger VM  This is rather aggravating, because every time it triggers a critical error a call home is generated. 
VxRail Manager treats appliances/components as missing