VxRail: RASR Process Fails With "Script 15_setup_node.sh execution error"

When attempting to reset DELL VxRail nodes using the RASR reset procedure, the RASR process may fail with the following error:
"Installation Status: ERROR: Script 15_setup_node.sh execution error"
 

There are two possible failure scenarios observed in the field:

1. The following messages can be seen in fist.log (VxRail: How to collect the logs to troubleshoot a RASR issue?)

"Failed to generate disk mappings, ERROR:('Invalid slot %s on disk %s', u'N/A', u'50000397bc896591')"

And

Got response from PTAgent. Code 200

2. During the RASR process, the following warnings were encountered while preparing the system:

Could not bring up network (Did not get an IP Address from DHCP server)

And the ipv4 address will always show 0.0.0.0 in DCUI. The following message is also shown in fist.log:

msg = '503 Service Unavailable (Failed to connect to endpoint: [N7Vmacore4Http16LocalServiceSpecE:0x03e100b8] _serverNamespace = /sdk action = Allow _port = 8307)' 

Scenario#1: This issue can be caused if the vxadmin account is removed from the iDRAC users list.
To check if the vxadmin user is present, connect to the iDRAC UI and goto iDRAC Settings->User Authentication.

Scenario#2: This issue can be caused by improper network configuration from the switch side. 

Scenario#1: If the vxadmin account is not present it must be added, see: VxRail: iDRAC settings that cannot be changed
Once the vxadmin has been added back with all appropriate permissions and password, reattempt the RASR procedure.

Scenario#2:  Disconnect the network cable from the switch and perform RASR again.