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Increasing the default value that defines the maximum number of NFS mounts on an ESXi/ESX host (2239)
This article provides information on:
- Configuring NFS TCP and NFS HEAP settings
- Identifying appropriate settings for
To edit advanced configuration options, select the ESXi/ESX host in the Inventory Panel, then navigate to Configuration > Software > Advanced Settings to launch the Settings window.
Set these values:
- Under NFS, Select NFS.MaxVolumes: Limits the number of NFS datastores which can be mounted by the vSphere ESXi/ESX host concurrently. The default value is 8, and can be increased to a maximum specific to the version of ESXi/ESX:
- ESXi/ESX 3.x: Set NFS.MaxVolumes to 32
- ESXi/ESX 4.x: Set NFS.MaxVolumes to 64
- ESXi 5.0/5.1/5.5: Set NFS.MaxVolumes to 256
- Under Net, Select Net.TcpipHeapSize: The amount of heap memory, measured in megabytes, which is allocated for managing VMkernel TCP/IP network connectivity. When increasing the number of NFS datastores, increase the default amount of heap memory as well:
- ESXi/ESX 3.x: Set Net.TcpipHeapSize to 30
- ESXi/ESX 4.x: Set Net.TcpipHeapSize to 32
- ESXi 5.0/5.1/5.5: Set Net.TcpipHeapSize to 32
- Under Net, Select Net.TcpipHeapMax: The maximum amount of heap memory, measured in megabytes, which can be allocated for managing VMkernel TCP/IP network connectivity. When increasing the number of NFS datastores, increase the maximum amount of heap memory as well, up to the maximum specific to the version of ESXi/ESX host:
- ESXi/ESX 3.x : Set Net.TcpipHeapMax to 120
- ESXi/ESX 4.x: Set Net.TcpipHeapMax to 128
- ESXi 5.0/5.1: Set Net.TcpipHeapMax to 128
- ESXi 5.5: Set Net.TcpipHeapMax to 512
- These settings enable the maximum number of NFS mounts for vSphere ESXi/ESX.
- Changing Net.TcpipHeapSize and/or Net.TcpipHeapMax requires a host reboot for the changes to take effect.
Modify the three advanced configuration options using the vSphere Client or other method. For a full list of methods, see Configuring advanced options for ESX/ESXi (1038578).
For more information on advanced NFS settings, see Definition of the advanced NFS options (1007909) and the Best Practices for running VMware vSphere on Network Attached Storage whitepaper.
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