Symptoms
LUNZ is associated to a variety of issues including hosts failing to boot, panics, and performance issues.
After initial set up, LUNZ was left presented to the host.
Cause
LUNZ refers to a fake logical unit zero presented to the host to provide a path for host software to send configuration commands to the array when no physical logical unit zero is available to the host. LUNZ is host operating system independent and can be presented by different EMC arrays including CLARiiON, VNX, and VPLEX.
As placeholder for connectivity, the LUNZ should be removed from the host following configuration. If the LUNZ remains visible to the host, a variety of issues can occur from a host failing to boot and panics to performance issues.
There are two primary reasons a host would see a LUNZ.
- The host HBA is connected to the array, but is not in a storage group or storage view.
- The host HBA is in a storage group or storage view, but the group/view does not have an HLU0 assigned.
Resolution
The best way to resolve the issue is to ensure host HBA is connected to the array and in a storage group or view containing a HLU0. Though it is possible to disable this form of communication on some arrays, it is generally not recommended.
Steps:
1.Register the host initiators on the array.
2.Assign storage to the host initiators in the storage group or storage view.
3.Ensure there is an HLU 0 in the storage group or storage view.
Additional Information
This articles has been promoted as HVC on EMC Community Network (ECN):
https://community.emc.com/docs/DOC-54136
Note: This article has been promoted as HVC on EMC Community Network (ECN):
https://community.emc.com/docs/DOC-54136