You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

ODY1980 Author

Level 1

9 points

Imac Pro - Crash when copy over 200GB on SMB !?

Hello, I have a really strange problem - since I upgrade to my new imac pro.

I really hoped for the 10.13.3 update - because it mentioned to fix SMB problems with crashes - but sadly it didn't help.

The problem I have is the following:

When I copy my VM Ware Folder (via 1Gbps ethernet cable) as a backup to a synology via SMB as soon as I hit around 200GB over the network the network of the imac stalls. No more receiving/sending - no more possibility to ping - even trying to disable and reenable the network doesn't work. No errors shown in any network utlity of bad packets etc. If I just wait then the mac just reboots itself without any error message and comes back.

What I tried so far:

1) Another imac Pro - same issue!
2) Even though the lockup happens on the imac (so it can't be solely related to the network itself) i tried to check if there is anything wrong in the network. Changed router, Change switch, Changed network cable etc. ! However with an old imac I can copy the file on the same line easily without any issues.

3) Tried different SMB settings 2.0 / 3.0 / disabled signing etc. - everything without any help.

For me its clear there is a severe driver issue with the new 10GB network port on the imac pros - but how can I truly identify the issue and report it to apple - so they take me serious without doing the normal troubleshooting...

If anyone has an idea, I would be more than happy to hear it 🙂

Like i said if i for example copy 50GB and then later 150GB - it will happen at 150GB - so it look like something is running full in a some kind of buffer at 200GB copy over network to smb.

Kind regards,
Oliver

macOS High Sierra (10.13.3), null

Posted on Jan 24, 2018 12:29 AM

Top-ranking reply

ODY1980 Author

Level 1

9 points

Posted on Jan 24, 2018 8:44 AM

Hey there - with your help I was finally able to find the issue.

Manually did not help me in the beginning because 1000T was correctly set by automatic. But automatic also sets the full duplex mode to:

full-duplex, flow-control, energy-efficient-ethernet

The problem here is the last option -> energy-efficient-ethernet <- this causes when using the SMB protocol and copying more than 200GB of data to the network to completly crash or stall the imac pro.

So all you need to do is changing it to manual and setting the full duplex to: full-duplex, flow-control

without this energy-efficient-ethernet - this also boosts your network speed by 2-3mb/sec.

I reported this to apple and hopefully they will make a fix with the automatic setting.

Kind regards,

Oliver

View in context

36 replies

Feb 19, 2018 4:08 PM in response to IndianaPwns

Cool thanks - are you just getting dropouts without crashes or kernel panics? Because that's what's happening with me - network drops out, but nothing else is affected, I just need to manually reboot to get the network back. No crashes, no hangs, no kernel panics.

Feb 19, 2018 5:17 PM in response to mustgroove

Just had a fantastic conversation with an Apple Enterprise Support Agent. It looks like High Sierra isn't playing nice (at all) with SMB. They have received a lot of calls and are aware of all the issues. They are working hard on a fix. The agent told me the newest 10.13.4 High Sierra update should fix 99% of them! HOOORAY!!!

ODY1980 Author

Level 1

9 points

Jan 31, 2018 11:54 AM in response to IndianaPwns

Try using apples external Gigabit Ethernet Adapter - if the problem is still happening, then you know it is not related to this specific problem.

Jan 31, 2018 11:56 AM in response to ODY1980

Great idea! We have a Sonnet Twin 10G Thunderbolt 2 adapter to try...will report back!

Feb 13, 2018 8:45 AM in response to Wunderlicht

Hey Wunderlicht,

Any updates from the Apple Team? Where they able to reproduce the issue?

Feb 19, 2018 8:21 PM in response to IndianaPwns

I just hope these iMac Pro issues don't fall into the 1% that 10.13.4 doesn't fix

Imac Pro - Crash when copy over 200GB on SMB !?