Network Tunning

Network Management :-
VM Directpath :- Bypasses the Virtualization layer and lets the Virtual device talk directly to a PCI physical Device.but this is lose features like vmotion,snapshots,memoery over-commitment,FT,VMsafe .(Avanced Configuration)
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Jumbo Frames :-Less processing and more throughput .normal ethenet payload is up to 1500 bytes payload with jumbo frame we can send payloads up to  9000 bytes . To send jumbo frames all devices  end to end should be enabled  and VMXnet (enhanced ) or VMXNET3 should be used for VM's.
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TCP Offload :-
TCP offload Engine(TOE) NIC feature is not supported by vSphere
TCP Segmentation Offload (TSO) supported by vSphere on some limited NIC -
" a feature of some NICs that offloads the packetization of data from the CPU to the NIC "

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NICO :- Network I/O Control (NIOC) from 4.1 require Vdistributed switch configured on DVSwitch
 Similar to SI/OC with NIOC you can use shares to prorotize virtual network bandwidth .
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VMCI (VIrtual Machine Communication Interface (VMCI))
Super fast coomunication option between host and VM or between VM and VM .ONly works with programs designed to work with socket API like a web application and backned database.Does not work with TCP/IP.

VMCI should be enabled on VM properties and must be installed.
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Network Metric's
net.usage.average
net.droppedRx.summation
net.droppedTx.summation
net.recived.average
net.trnasmitted.average
net.usage.minimum
net.usage.maximum.
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esxtop --n for networking
       -- f for options
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How to find if network is the problem
Primarly look at the usage in KBps and see if exceeding the bandwidth of the netwrokinterface
Drop packets
No traffice sent /recived
Errors on physical switch port.
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