Home » VMware » VCP550D » What is the expected behavior of an ESXi host when a failed preferred path becomes available using the Fixed path selection policy for this array type?
An administrator has configured multi-pathing using a Fiber Channel array in an active-active configuration.
What is the expected behavior of an ESXi host when a failed preferred path becomes available using the Fixed path selection policy for this array type?
A. It automatically reverts to the preferred path.
B. It continues using the current path until it is manually reverted.
C. It resumes load balancing across all available paths.
D. It reverts to the preferred path after the host has been restored and rebooted.
Correct Answer: A
Explanation/Reference:
Explanation:
To maintain a constant connection between a host and its storage, ESXi supports multipathing. Multipathing is a technique that lets you use more than one physical path that transfers data between the host and an external storage device.
In case of a failure of any element in the SAN network, such as an adapter, switch, or cable, ESXi can switch to another physical path, which does not use the failed component. This process of path switching to avoid failed components is known as path failover.
The Fixed pathing policy uses the designated preferred path flag, if it is configured. If the ESXi/ESX host cannot use the preferred path or it becomes unavailable, the ESXi/ESX host selects an alternative available path. The host automatically returns to the previously defined preferred path as soon as it becomes available again. This is the default policy for LUNs presented from an Active/Active storage array.
Incorrect Answers:
B: The host will not continue using the current path until it is manually reverted. It will automatically revert to the preferred path. Therefore, this answer is incorrect.
C: The host will not resume load balancing across all available paths. It will automatically revert to the preferred path. Therefore, this answer is incorrect.
D: The question states that the preferred path becomes available. Therefore, the host is functioning correctly and does not need to be restored. It also does not need to be reverted. The host will detect that the preferred path is available and revert to using the preferred path. Therefore, this answer is incorrect.
References:
http://pubs.vmware.com/vsphere-55/index.jsp#com.vmware.vsphere.hostclient.doc/GUID-DD2FFAA7-796E-414C-84CE-1FCC14474D5B.html
http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1011340