nfnic driver limits device detection to LUN IDs of 256 and below (preventing additional device detection)
Article ID: 338057
Updated On:
Products
Issue/Introduction
Impact/Risks:
The new NFNIC driver does honor UCS HBA profile limitations which can inadvertently lead to loss of storage device detection.
Symptoms:
- You have recently upgraded ESXi and can't see all your storage devices.
- You have LUN IDs numerically higher than 256
- You see errors like the following in vmkernel.log:
2019-02-06T18:56:48.222Z cpu6:2097702)WARNING: ScsiScan: 2384: Skipping out-of-range LUN vmhba2:C0:T2:L314 Max LUN ID supported by the driver is =256
2019-02-06T18:56:48.223Z cpu26:2097699)WARNING: ScsiScan: 2384: Skipping out-of-range LUN vmhba1:C0:T2:L315 Max LUN ID supported by the driver is =256
2019-02-06T19:01:48.247Z cpu19:2097702)WARNING: ScsiScan: 2384: Skipping out-of-range LUN vmhba1:C0:T1:L316 Max LUN ID supported by the driver is =256
2019-02-06T19:01:48.248Z cpu25:2097705)WARNING: ScsiScan: 2384: Skipping out-of-range LUN vmhba2:C0:T1:L317 Max LUN ID supported by the driver is =256
2019-02-06T19:01:48.250Z cpu19:2097702)WARNING: ScsiScan: 2384: Skipping out-of-range LUN vmhba1:C0:T2:L318 Max LUN ID supported by the driver is =256
2019-02-06T19:01:48.250Z cpu25:2097705)WARNING: ScsiScan: 2384: Skipping out-of-range LUN vmhba2:C0:T2:L319 Max LUN ID supported by the driver is =256
2019-02-06T19:06:48.275Z cpu26:2097700)WARNING: ScsiScan: 2384: Skipping out-of-range LUN vmhba1:C0:T1:L320 Max LUN ID supported by the driver is =256
Environment
VMware vSphere ESXi 6.x
VMware vSphere ESXi 7.x
VMware vSphere ESXi 8.x
Cause
Cisco's UCS profile manager has had traditionally maximum storage device IDs limited to 256.
However previous implementations of the FNIC driver have not honored these limitations.
Resolution
Cisco is aware of this potential impact and modification of the UCS profile may be necessary to mitigate.
Customers should contact Cisco UCS support if they encounter the aforementioned symptoms coupled with the referenced errors in vmkernel.log
As a workaround, the Cisco vendor can modify the 'Max LUNs per target' parameter on the UCS profile to a higher number to fix the issue.
Additional Information
NetApp has identified this behavior in their storage product line (Cisco UCS using NetApp storage backend) and confirmed the current resolution. This KB further outlines the problem from their perspective Troubleshooting LUN connectivity issues on ESXi hosts (NetApp login required)
Impact/Risks:
The new NFNIC driver does honor UCS HBA profile limitations which can inadvertently lead to loss of storage device detection.
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