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perlausten
Contributor
Contributor

vmnet-natd uses 100% of one CPU core

The vmnet-natd process frequently starts using 100% CPU of one of the cores on my MBP. The only workaround is to suspend my VMs and restart VMware Fusion.

I run two VMs: Windows 8.1 and OpenSUSE. Both VMs use "Share with my Mac" as network setting.

Does anyone know a working fix?

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15 Replies
ColoradoMarmot
Champion
Champion

This was an old bug that was fixed.   What version of Fusion are you running?

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perlausten
Contributor
Contributor

I am using 6.0.3.

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datpete
Contributor
Contributor

I have this problem too.

Using Fusion 7.0.0 running bootcamp with windows 7 (shared IP / nat chosen).

Come on VMWare, please fix this!

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avanish321
Expert
Expert

Are you using any packet sniffing apps or antivirus programs on the Mac host or in the Guest Virtual Machine ? If yes, try disabling them and check if that's making any difference.

Cheers! Avanish
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ColoradoMarmot
Champion
Champion

System restore can also trigger this - especially on rarely used VM's.

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perlausten
Contributor
Contributor

I now run Fusion 7.0.1 and still have the issue!

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perlausten
Contributor
Contributor

I am now using Fusion 7.1.0 and it is still an issue!

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nancyz
VMware Employee
VMware Employee

Hi perlausen,

Thanks for using Fusion. Did you run any specific tools in your VM?

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perlausten
Contributor
Contributor

Sure, I do.

Yesterday I disabled Windows 8.1 network discovery and have since yesterday not yet seen the usual vmnet-natd high cpu usage. I will let you know in a few days if it helped.

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perlausten
Contributor
Contributor

Disabling Windows 8.1 network discovery did not help. This morning I am again seeing 100% CPU usage from vmnet-natd.

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Maclinux42
Contributor
Contributor

perlausten wrote:

I am now using Fusion 7.1.0 and it is still an issue!

And I'm just observing the same issue with Fusion 7.1.1, too.

Btw, my guest operating system is Debian 7.6.

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Maclinux42
Contributor
Contributor

It's pretty bad, a few minutes after starting VMware Fusion and my Linux guest the vmnet-natd is now always at 100%.

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www23456
Contributor
Contributor

do you have a sample log for vmnet-natd process? Or any sniffer trace for vmnet8 device?

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Maclinux42
Contributor
Contributor

I can't submit a sniffer trace because I can't freely disclose the network traffic and I don't really have the time to make a sample log, I was hoping that such an obvious issue would get fixed "by itself", but I'll look into it -- or change to another virtualisation software -- really soon.

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dariusd
VMware Employee
VMware Employee

Although the symptoms you're observing might be obvious, the cause is anything but obvious.  I am a very frequent user of Debian 7 and Debian 8 guests inside Fusion, and I have not observed any problem.

If you are sure that the NAT is not being flooded with packets (from the guest, the host or the external network), it's quite possible that some specific combination of factors in your environment is triggering a defect in the NAT daemon that leads to the problem you're seeing.

Possible factors that might lead to the problem being difficult to reproduce here: It could possibly be triggered by your physical router's NAT daemon or your DNS service; It could be triggered by some other device or software on your network (possibly even malware!); It could be related to some other aspect of the configuration of your Mac that does not match what we're using here, possibly some other software running on the Mac itself.

If you are able to reliably reproduce the problem, a sample log for the vmnet-natd process has a good chance of helping us understand what's going on.

Thanks,

--

Darius

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