Troubleshooting network access from ESXi host to NFS data store

Products

• VMware vCenter Server

Issue/Introduction

The NFS data store is unreachable from the ESXi host.

An error message is seen in vSphere Client that the host failed to connect to the IP address of the datastore.

This error can occur even when the target IP address for the datastore is reachable from virtual machines (VMs) on the ESXi host and/or other network clients such as jump boxes.

Cause

Connecting to an NFS datastore requires that the ESXi host be able to reach the datastore target IP address using a VMkernel.

Connectivity to this IP address requires, among other things, that the VLAN required to reach this IP (if applicable) is both properly tagged on the port group and permitted by the upstream switch on the port that correlates to the uplink (physical NIC) used by the VMkernel. If the upstream switch does not permit the VLAN, access is denied.

There is no service checkbox for NFS datastores; the host will choose the VMkernel (and by consequence the port group and physical uplink NIC) based on the host's routing table, which can be confirmed with the command esxcli network ip route ipv4 list

Resolution

Ensure that the VLAN needed to reach the NFS datastore IP address is enabled in the switch configuration settings.

Contact your network team if assistance is needed to confirm these settings.

 

These steps can help you identify the uplinks, subnets and VMkernels involved in accessing your datastore:

The subnets associated with VMkernels can be reviewed in vSphere Client or using the command esxcli network ip interface ipv4 get

The route table can be reviewed with the command esxcli network ip route ipv4 list

The uplinks can be reviewed in vSphere Client or using the commands esxcli network vswitch standard list , esxcli network vswitch dvs vmware list

The VLANs can be reviewed in vSphere Client or the command esxcli network vswitch standard portgroup list for a standard virtual switch

Reachability to an IP from a VMkernel can be tested with the command vmkping -I <vmk> <ip_address> 
where <vmk0> and <ip_address> are replaced with the VMkernel name and IP address, i.e. vmkping -I vmk0 192.168.0.2