Adding a bnx2 network interface card fails with the error: Unable to add uplink! The MTU setting used by this virtual switch is not support by the NIC being added

Products

• VMware vSphere ESXi

Issue/Introduction

Symptoms:

When running ESXi 5.5, adding a Broadcom bnx2 Network Interface Card (NIC) to a vSwitch configured to use a large MTU. For example, MTU 9000 (jumbo frames), you experience these symptoms:

• You see an error in the vSphere Client similar to:
  
  Unable to add uplink! The MTU setting used by this virtual switch is not support by the NIC being added
  
  
• In /var/log/vmkernel.log, on the ESXi 5.5 host, you may see messages similar to:
  
  cpu12:32852)WARNING: Heap: 3622: Heap vmklnx_bnx2 (68473704/68481896): Maximum allowed growth (8192) too small for size (69632)
  cpu12:32852)WARNING: Heap: 3622: Heap vmklnx_bnx2 (68473704/68481896): Maximum allowed growth (8192) too small for size (69632)
  cpu12:32852)WARNING: Heap: 4089: Heap_Align(vmklnx_bnx2, 65536/65536 bytes, 8 align) failed. caller: 0x418006b85a9a
  cpu12:32852)<3>bnx2 0000:01:00.0: vmnic0: Cannot allocate firmware buffer for uncompression.
  cpu12:32852)<3>bnx2 0000:01:00.0: vmnic0: failed init nic during MTU change
  cpu12:32852)WARNING: Uplink: 9650: Failed to set MTU to 9000 on vmnic0
  
  
• The ESXi host reports a not responding state when you try to add a NIC to a Standard switch or virtual Distributed Switch (vDS).
• The ESXi hostd management agent stops responding and fails to restart.

Environment

VMware vSphere ESXi 5.5

Cause

The cause of this issue is due to a problem with the heap memory management for the Broadcom bnx2i driver.

Resolution

This is a known issue affecting ESXi 5.5. Currently, there is no resolution.

To workaround this issue when your system is not using hardware iSCSI, such as bnx2i, disable the driver. Also, increase the heap memory for the bnx2i driver.

To disable the bnx2i driver and increase the heap memory available for bnx2i managed devices:

1. Open an SSH session to the ESXi 5.5 host. For more information, see Using ESXi Shell in ESXi 5.x (2004746).
2. To disable bnx2i run this command:
   
   # esxcli system module set -m bnx2i -e 0
   
   
3. To increase the heap memory for the bnx2 driver run this command:
   
   # esxcli system module parameters set -m bnx2 -p "heap_max=134217728"
   
   
4. Reboot the ESXi 5.5 host for the changes to take effect.
5. Confirm that the settings are applied using these commands:
   
   # esxcfg-module -g bnx2i
   
   You see output similar to:
   
   bnx2i enabled = 0 options = ''
   
   # esxcfg-module -g bnx2
   
   You see output similar to:
   
   bnx2 enabled = 1 options = 'heap_max=134217728'

Additional Information

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For more information, see the VMware vSphere 5.5 Networking Guide.

For more information about the hostd management agent failures, see Troubleshooting vmware-hostd service if it fails or stops responding on an ESX/ESXi host (1002849).

Troubleshooting vmware-hostd service if it fails or stops responding on an ESX/ESXi host
Using ESXi Shell in ESXi 5.x and 6.x
次のエラーで bnx2 ネットワークインタフェースカードを追加できない：Unable to add uplink! The MTU setting used by this virtual switch is not support by the NIC being added