An ESXi 6.x host in the vCenter Server inventory has disconnected due to an All Paths Down (APD) situation. An administrator has corrected the APD issue on the
host, but it still remains disconnected.
What action should the administrator take next?
A.
Select Restart Management Agents from the DCUI.
B.
Execute esxcli system settings advanced set -d /Scsi/FailVMIOonAPD.
C.
Modify the advanced parameter /Disk/ApdTokenRetryCount.
D.
Enable the advanced parameter /Misc/APDHandlingEnable.
Explanation:
D is correct
https://pubs.vmware.com/vsphere-60/index.jsp?topic=%2Fcom.vmware.vsphere.storage.doc%2FGUID-54F4B360-F32D-41B0-BDA8-AEBE9F01AC72.html
Agree. This question is tricky, because hosts running versions of ESX/ESXi 4.x and 5.0 do not have advanced setting Misc.APDHandlingEnable and they need to restart Management Agent instead.
This question talks about ESXi 6.x host which has the advanced parameter Misc.APDHandlingEnable.
If we assume they disabled Misc.APDHandlingEnable then ESXi should work like ESXi 4.x or 5.0 since the threads are tied up with searching for storage and disconnected from vCenter. If the APD issue has been fixed I’m not sure by enabling Misc.APDHandlingEnable will allow the ESXi host to connect back up to the vCenter since hostd is probably hosed. Therefore you will need to restart the management agents.
Like this guy did in step 2:
http://www.fivepointtech.com/home/third-party/recovering-from-a-hostd-unresponsive-event
A is correct
https://kb.vmware.com/kb/2126021
Resolution
Note: It may also be necessary to restart ESXi management agents. For more more information, see Restarting the Management agents on an ESXi or ESX host (1003490).
A is correct.
A, is reactive. While D is proactive. The question states that host has already disconnected.
A note about APDHandlingEnabled, it is on by default in 6. So the host will try to reconnect for a certain period of time, then stop. Remember when you would yank storage from a host, then some time later it would crash? This stops that. You can disable it, and the host will try to reconnect forever. Babar’s link has the detail.
I believe what tripped up people saying D was this line: “If you disabled the APD handling, you can reenable it when a device enters the APD state. The internal APD handling feature turns on immediately and the timer starts with the current timeout value for each device in APD.” Basically, you are just turning on a timer (140 sec by default). If APDHandlingEnabled was disabled, and the host cannot connect, HostD is messed up and needs to be restarted.