Thank you for the information. This appears to be siomewhat different than the earlier issue where the LAN perfomance itself was the problem (slow connections).
I'll work on reproducing your issue here, so will need some additional information from you to make sure I configure everything to match yours:
- BIOS version currently installed on the NUC
- SA# of the NUC (on the label on the bottom)
- Are you configured for both wired and wireless LAN? If both, what wireless LAN card are you using?
- what LAN driver version do you have installed? (And if wireless is there, which wireless driver version?)
- what tool/utility are you using to see the connect/disconnect issue?
- any other configuration info that may be a factor (switch, router, etc)
I RMA'd the hardware and have received a replacement. Unfortunately, the new hardware exhibits the same symptoms which leads me to believe that this is likely a software driver issue.
I can get the BIOS version and SA# shortly, but here are some other details:
- This is wired LAN only, there is not a wireless adapter installed in the unit
- NIC: 82579LM driver version 18.5
- The disconnects are visible on the physical adapter status LEDs. Further there are several event logs that point to this issue
- The adapter is connected directly to a Cisco C2970G (while this looks like a spanning tree issue, it is disabled on the interface). Further any other device connected to this interface do NOT have this issue
The event logs are riddled with the following:
Event ID: 27
Intel(R) 82579LM Gigabit Network Connection
Network link is disconnected.
Further, I can physically see the link drop then reconnect, then drop then reconnect.
Per other forum posts around, I have disabled the SIPS feature in the driver. This issue still occurs with either the basic driver set or full ProSET - though the basic drivers don't seem to be as bad.
I have worked around the issue by doing the following:
- Not allowing the NIC to sleep to save power
- Disabling 'energy efficient ethernet'
- Disabling SIPS
That being done seems to allow the system to come out of S3 without dropping connection - however a full reboot still has issues.
I currently do not have a switch available that I can use to reproduce the same layout as you have. I'll see about getting one. In the meantime, I found something interesting on Cisco's website about interoperability with Intel LAN solutions at http://www.cisco.com/en/US/products/hw/switches/ps708/products_tech_note09186a00800a7af0.shtml#nic_comp
Here is their recommendation to workaround connection issues:
1. In Device Manager, choose Network Adapters and then the Intel LAN adapter you have.
2. At the Power Management tab, uncheck Allow the computer to turn off this device.
Please give this a try and let me know what happens.
Our engineering team would definitely need to have a system exhibiting this behavior in order to debug and find a solution. If we are unable to find the right combination here to reproduce the problem, would it be at all possible for you to send us the failing system?
The note on the Intel site is specific to the PRO100\1000 series chipsets - while I don't know how close the chipsets are. Further, the workaround does not work - as I noted previously, allowing the computer to turn off the NIC worsens the issue.
I can connect to a different switch - however I doubt this will make a difference as no other devices on the network have this issue - and again both the old as well as this NUC exhibited this issue.
I am not able send the device in currently.
I had the exact same issue with the i5 version of the NUC. The NIC would have difficulties to connect. Unfortunately I didn't have the option to connect via the mini display port as I use it as an HTPC. After days of struggling I returned the unit and purchased another piece from newegg and that has been flawless since. I believe there is an inherent defect on the NUC boards that cause this issue to uncover itself.
I tried the RMA process but since the i5 version of the NUC was new and intel didn't have it in stock, I went through the exchange process. One thing to note. the one I purchased on Amazon wasn't sealed in shrink wrap as the one I received from newegg.
I've seen this issue on an i3 version of the NUC as well but in that case switching to the furthest hdmi port fixes the issue. But in my opinion all ports if provided should work.
I've been working on various combinations of NUCs, OS versions, with and without a Cisco C2950 switch and have found the following:
- I see the Event ID 27 both with and without the switch on Windows 7, but I don't have the long period of connect/disconnect after waking from sleep
- I never see Event ID 27 on any of the Windows 8 configurations
I have asked my colleagues in the LAN team to take a look at this and will let you know what I find out.