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jatinjsk
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What is the ideal MTU Size for NFS Storage in VMware?

Hello,

We have performance issues on Storage where NFS Volumes GAVG/cmd goes upto 200 and keep fluctuating betwwen 150 to 200. This happens whenever we clone a VM or migrate a VM.

Upon checking multiple things it was noticed that MTU at storage side is set to 1500 and at vSwitch side it is set to 9000.

1. What should be MTU Size for NFS Storage at both end?

2. is there any way we can determine ideal MTU for a specific network?

Thanks,

Jatin

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Alex_Romeo
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Hi,

The rule is that it must be set to both at the same value.

1500 - 1500

9000 - 9000

The MTU size can be very important because it determines packet fragments on the network. If your chunk size is 8KB and the MTU is 1500, it will take six Ethernet frames to transmit the 8KB. If you increase the MTU to 9000 (9,000 bytes), the number of Ethernet frames drops to one.

The most common recommendation for better NFS performance is to set the MTU on both the NFS server and the NFS client to 9000 if the underlying network can accommodate it.

Alessandro Romeo

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Alex_Romeo
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Hi,

The rule is that it must be set to both at the same value.

1500 - 1500

9000 - 9000

The MTU size can be very important because it determines packet fragments on the network. If your chunk size is 8KB and the MTU is 1500, it will take six Ethernet frames to transmit the 8KB. If you increase the MTU to 9000 (9,000 bytes), the number of Ethernet frames drops to one.

The most common recommendation for better NFS performance is to set the MTU on both the NFS server and the NFS client to 9000 if the underlying network can accommodate it.

Alessandro Romeo

---------------------------------------------------------------------------------------------------------

Was it helpful? Let us know by completing this short survey here.

Blog: https://www.aleadmin.it/
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5mall5nail5
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The MTU is whatever is set on the vmkernel and vswitch.

Ideally 9000.

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VM_Niels
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How could I (which tools) the performance of NFS datastores with MTU 1500 and MTU 9000?

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