Writing images from a Cognex machine vision camera to a NAS RN31400

[GDA_LLC]

I am saving inspection images from two Cognex machine vision cameras to the NAS using the built in FTP server.  I need to know the settings of the NAS that will allow the most images to be written to the NAS.  When we run the machine at full rate we only get about 1/3 of the images successfully written to the NAS.  What settings should I look at that might be holding back the maximum throughput?

Images are 2Mb each, we are sending them once very 250ms, so 2Mb x 2 cameras x 4 times per second = 16Mb/sec, not anywhere near 100Mb/second!?!?  What is holding this back from transfering all of the images?  Cameras are going through a Cisco Managed Ethernet swtich with very little other network traffic (only a PLC and HMI, not connected to a plant wide network).

Any thoughts or direction would be appreciated.

Greg

[StephenB]

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GDA_LLC wrote:

Images are 2Mb each, we are sending them once very 250ms, so 2Mb x 2 cameras x 4 times per second = 16Mb/sec, not anywhere near 100Mb/second!?!?  

Are you using megabytes or megabits here?  Are you running fast ethernet or gigabit on the network path?

[GDA_LLC]

the Cognex cameras only have 100Mb ethernet to the switch.  From the switch to the NAS I have one GB Ethernet connection.  The NAS has two ports so I wasn considering setting up the IP address of the second port and having each camera write to one of the ports.  Image are in Megabytes.

Greg

[StephenB]

It's not completely clear to me where the bottleneck is.

You could

(a) retarget the cameras to point to a PC running an FTP server (perhaps FileZilla) and see if that performs differently

(b) aim two FTP clients at the NAS from PCs, and attempt simultaneous uploads of a group of 2 megabyte files, and measure the NAS FTP server throughput.

Those two tests should help sort out where the problem lies.