28 Replies Latest reply on Oct 28, 2015 12:55 AM by peteroakes

    Raspberry Pi loses ethernet

    iceman358

      Hello there.

      After several attempts to search this forum and not having found a solution, I decided to create a new discussion.

       

      My Raspberry is a headless setup with a disk (externally powered) that I use as a downloader (transmission) and a file server (samba).

      Sometimes it works for days in a row, sometimes it gets stuck and does not even acquire an IP address.

       

      When it does not have an IP address I cannot determine what is wrong.

      I have it plugged in to my router, the lights on the board itself light up and the light of the router that says it is connected also lights up.

      The router does not recognise the Pi (it is not shown at the DHCP client list) and the Pi cannot ping the router.

      Also, the Pi sees if the cable is removed. (the lights turn off and dmesg says eth0 is unplugged).

       

      /etc/network/interfaces has dhcp enabled (although when I try to convert it to static and reboot the Pi says it has an IP address but cannot even ping the router and the router does not find it)

      /etc/resolv.conf also has my router IP

       

      I am at a deadend. If anyone could help me I would really appreciate it.

       

      PS. I also used my multimeter at the TP1 TP2 connectors and got a result of 4.99V.

        • Re: Raspberry Pi loses ethernet
          John Beetem

          Here's one suggestion from the RasPi Troubleshooting Wiki: you may be getting a burst of activity which overflows USB kernel memory.

           

          I suggest getting a UART adapter cable that you can plug onto the 3.3V UART pins on the GPIO connector.  That way you can talk to RasPi without going through the LAN9512, which has likely crashed.  Here's a thread on the topic chez RasPi.

            • Re: Raspberry Pi loses ethernet
              iceman358

              Well, I don't have that much knowledge in that region. Can I do nothing at software level?

               

               

               

              Also, from the little I know about hardware, it seems to me that many of the soldered parts of my Pi are cold joints (they do not look shiny, but kind of white).

              Again, I do not know much about this, so here is a photo of my Pi.

              20121227_182855.jpg

                • Re: Raspberry Pi loses ethernet
                  msilveus

                  I hope the unit I have arriving tomorrow does not look like that, as you are quite right those are bad solder joints. I have the tools to fix mine if it comes to that but who ever is built your unit certainly should have failed it at the QC stage and sent it back for rework.

                   

                  Mike

                    • Re: Raspberry Pi loses ethernet
                      iceman358

                      And now it decided to work again and find the network... (no changes made whatsoever)

                       

                      Can anyone suggest something for mr to do to troubleshoot?

                       

                       

                       

                       

                      (general response, not to you only, I'm new here)

                        • Re: Raspberry Pi loses ethernet
                          efflandt

                          See what /var/log/syslog says when that happens.  Whether you are using wired or wireless, if you start getting errors about its built-in ethernet, that can also interrupt anything else on USB.  The first one I got did that more often, and 2nd 2 would also do that at random periods of time.  Installing all updates regular updates did NOT help: sudo apt-get update && sudo apt-get dist-upgrade -y

                           

                          What did help was doing rpi-update.  I don't think I have had that problem with any of them since doing that.  For example my 1st "troublesome" one has no problems running headless with only mini-WiFi attached:

                           

                          efflandt@raspberrypi ~ $ uptime

                          10:30:28 up 2 days, 10:23,  1 user,  load average: 0.04, 0.08, 0.06

                          efflandt@raspberrypi ~ $ lsusb

                          Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

                          Bus 001 Device 002: ID 0424:9512 Standard Microsystems Corp.

                          Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp.

                          Bus 001 Device 004: ID 0bda:8176 Realtek Semiconductor Corp. RTL8188CUS 802.11n WLAN Adapter

                           

                          For rpi-update see https://github.com/Hexxeh/rpi-update/

                          If you have any trouble with wget not resolving ipv6 add following to /etc/wgetrc: inet4_only = on (that begins with small eye)

                          You also need to sudo apt-get install git-core, which rpi-update will tell you if you have not installed that.

                            • Re: Raspberry Pi loses ethernet
                              tobiz

                              I've tried all these options, changed power supplies (5v 2.1A), run rpi-update etc etc but still the problem persists. My conclusion is that there is either a serious h/w or driver bug. I did notice en route that there is an interaction between the lan and usb connections, eg unplugging a usb device would cause a reboot, having the lan and usb mouse connected on boot and the mouse doesn't work.  At the moment I'm running with only a lan connection, no others, connecting in via ssh or vnc, so the lan has to work.  On the whole a complete mess! At the moment I'm running without a case to see if there is an overheating problem; initial conclusion is that the lan stays up for longer but eventually drops out.  I'll eliminate other potential sources of problems, h/w, cables, routers etc since these aren't a problem for any of the other systems I run, including an early RasPi.  What I will do next is run the SD card in my old RasPi and if the problem doesn't show up then my conclusion is a h/w or driver problem in the recent board (it's about 1 year old). If rpi-update does install new driver/chip firmware then either that has a bug or there's a bad joint, bad component or some such on my board and I assume on others who have experienced the same conditions

                                • Re: Raspberry Pi loses ethernet
                                  John Beetem

                                  I always recommend checking through the RasPi Troubleshooting Wiki, especially the parts about start-up and power problems.  The best way to check power problems is to measure the voltage between TP1 and TP2.  If it's less than 4.75V, that could be a problem and the power section of the Wiki tells you what to look for next, e.g., an iffy polyfuse F3.  Micro USB power cables sometimes have very thin conductors and you can get enough of a drop to cause problems, even if your 5V 2.1A supply is working perfectly.

                                   

                                  The newer RasPis with the mounting holes do not support hot swap of USB devices.  You should be able to unplug one without grief, but plugging in a USB device may cause a 5V glitch large enough to reboot.

                                    • Re: Raspberry Pi loses ethernet
                                      tobiz

                                      Thanks for that re the power supply and the USB hot swap issue (I can live with that since I don't have any USB devices connected just a 1GB LAN).  I still don't think the problem is the power supply since having tried several (ie 4 some up to 2A, and one was supplied with the RasPi so really should be up to the job)) I get the same LAN drop out problem.  The latest is that when not in a case it runs for longer, 5-10mins but will always drop out eventually (this might suggest something but not convinced).  I still intend to try my current SD card built on the problem PI in my old (ie early running ok for ~1yr) RasPi to see what happens then.

                                        • Re: Raspberry Pi loses ethernet
                                          Roger Wolff

                                          I have four raspberry pi's that I run "headless":

                                          vitalstatistix:~> uptime
                                          09:46:31 up 48 days, 19:56, 12 users,  load average: 0.50, 0.39, 0.31

                                          raspberrypi:~> uptime
                                          10:46:41 up 46 days, 15:39,  5 users,  load average: 0.00, 0.01, 0.05
                                          dogmatix:~> uptime
                                          10:46:53 up 45 days, 17:25,  1 user,  load average: 0.08, 0.04, 0.05
                                          raspberrypi:~> uptime
                                          09:46:29 up 38 days, 21:08,  5 users,  load average: 0.16, 0.05, 0.06

                                          two are "experimenting" machines that haven't gotten their hostname changed from "raspberrypi".  (Hmm. And two are running in a different timezone....)

                                           

                                          So I'm thinking it has something to do with /your/ setup.

                                           

                                          On the other hand, I'm running all of them "diskless": The filesystem is NOT on the SD card, but on a server connected through the LAN.... So I'm getting very little SD card IO...

                                           

                                          /IF/ the powersupply is "bad", the LAN chip is the first that shows signs of not-working. I've put the raspberry pi on a bench supply and turned the voltage down. At 4.3V the 3.3V powerline starts dropping. At 4.0V the 3.3V line has dropped down to 3.0V and that's when the lan chip stops working. As a matter of fact, the CPU SHOULD continue to work down to about 3V. on the 5V line. But e.g. there is a 1.8V that is used to communicate between the RAM and the CPU that might drop too far to keep things running. I haven't checked this.

                                           

                                          So if you're seeing lan-chip-crashes, that is still a hint that there might be a problem with your powersupply.

                                           

                                          What most people don't realize is how bad the cheap USB cables are. So even if you have a perfect 4A powersupply, the cable might cause a voltage droop. On the other hand, if you've measured TP1/TP2 to be 4.99V that doesn't seem to be the problem either. So... sorry I don't have a clear answer for you. :-(

                                            • Re: Raspberry Pi loses ethernet
                                              gallomimia

                                              Agreed with many above posters. This sounds like a power problem. I recommend you measure the voltage under full load with a network file transfer running. This will show if the voltage drops under load and stays high while idle. Because this does sound like what the problem is.

                                                • Re: Raspberry Pi loses ethernet
                                                  tobiz

                                                  I've now run the old RasPi with the SD built on the failing new RasPi; result - no problems with the network even under heavy load.  This seems to rule out a problem with the build of the SD card.  The next step will be to run the old RasPi with the new SD build but the power supply provided with the new RasPi (I'll also try the other RasPi/power supply combination).  I would say that of course the problem with the new RasPi could be a power supply problem.  However that means the 3 power supplies I've tried, all from different manufacturers, all rated at 5V but one at 1000mA, one at 1200mA, one at 2.1A all have the same problem of voltage drop under load.  Of course possible but it seems to me to be unlikely, I'm not ruling it out but unlikely.

                                                    • Re: Raspberry Pi loses ethernet
                                                      netnut

                                                      I have exactly the same problem. Tried two different Pi's and both lose the ip address after 20-30 hours of operation. I am trying to run headless so once the ip address is gone, I cannot access using ssh. I am using 3.10.25+ #622 from the NOOBS/Raspian release. raspberry Model B. SONY 16GB Class 10 SD. Powered by a 2.1Ax5V Anker power supply.

                                                      An Arduino UNO is connected to one USB and an RS232->USB cable to the other USB. Disconnecting these peripherals does not seem to help.

                                                      syslog does not show anything is up.

                                                      The first symptom is that all the LAN lights disappear. Then resetting the board via GPIO does not help. The board needs to be powered down and powered up again risking corruption of the SD card.

                                                       

                                                      I am about to give up on the headless approach and move to an Arduino with an Ethernet shield, but it will be difficult to fit my program into 32KB.

                                                       

                                                      Any help appreciated.

                                                       

                                                      SJ

                                                        • Re: Raspberry Pi loses ethernet
                                                          Roger Wolff

                                                          Hi,

                                                          My raspberry pi's have uptimes in the order of "months" because on that timeframe I move them and they get powered down.

                                                           

                                                          /IF/ your powersupply is insufficient, the first component to be troubled by that will be the SMC ethernet chip. Can you doublecheck that your powersupply is good? Is it capable of providing 1A? Have you used a sufficiently thick (electrically) cable? Have you tried "backfeeding" the 'pi? Take a powered hub and connect it to the pi's  USB connector...

                                                            • Re: Raspberry Pi loses ethernet
                                                              tobiz

                                                              My old pi has been running now for several days without ethernet drop out running the build I made on the failing new pi. The old pi is running the old power suply, I've not tried it yet on the new pi power supply. As I said in a previous post the new pi had this problem even when I tried it on 3 different power supplies, rated up to 2.1A, so my view is the ps is not the problem. BTW the new pi had this ethernet drop out originally after running for several tens of hours,it now shows the problem after minutes. The usb 'back power' work around sounds a serious 'fudge'! If it works it suggests the unit is not fit for purpose, some not all. It sounds like a manufacturing component failure. I'm quite prepared to send mine back if that will help solve the problem for others, having one that works is all I need really.

                                                                • Re: Raspberry Pi loses ethernet
                                                                  Roger Wolff

                                                                  To get power from the powersupply to the raspberry pi, you need a cable. Some horrendously bad cables are around. So, buy a cable from Farnell and/or take the cable from your HTC phone. Those are good. You can buy the USB prodder from my company to measure the resistance of your cables with a multimeter if you want.

                                                                   

                                                                  Most people advise to measure the voltage between TP1 and TP2 on the raspberry pi. The reading should be about 5V. But the problem is that worst case the powersupply+cable cannot provide the current required for short bursts. So if the reading is say 4.9V, it might be that there is 5V for 90% of the time and 4V for 10% of the time. The actual relationship will be more like 99.9 versus 0.1%. And chips will crash if they have too little power for only a very short time. So get that better cable!

                                                                    • Re: Raspberry Pi loses ethernet
                                                                      tobiz

                                                                      Ok, I've now run my old RasPi with the SD card built on the new failing

                                                                      one and powered the old one by the new power supply, result - no

                                                                      ethernet dropout after running for about 4 hours (the new RasPi fails in

                                                                      about 4 mins).  I think I've now established to my satisfaction that

                                                                      there is something seriously wrong with my new RasPi and there is no

                                                                      other unit, power supply, SD card, ethernet router, ethernet cables etc

                                                                      etc that is the problem.

                                                                       

                                                                      In both cases the only connection either RasPi has is an ethernet

                                                                      connection, no USB, no HDMI, absolutely nothing but the power supply.

                                                                      So if anyone else gets the ethernet dropout problem one of the possible

                                                                      causes can be the RasPi itself.  Of course in some cases it could be the

                                                                      power supply or any of the other diagnosis mentioned but the RasPi being

                                                                      the problem is a possibility.  I hope that helps.

                                                                        • Re: Raspberry Pi loses ethernet
                                                                          John Beetem

                                                                          Peter Robinson wrote:

                                                                           

                                                                          Ok, I've now run my old RasPi with the SD card built on the new failing

                                                                          one and powered the old one by the new power supply, result - no

                                                                          ethernet dropout after running for about 4 hours (the new RasPi fails in

                                                                          about 4 mins).  I think I've now established to my satisfaction that

                                                                          there is something seriously wrong with my new RasPi and there is no

                                                                          other unit, power supply, SD card, ethernet router, ethernet cables etc

                                                                          etc that is the problem.

                                                                           

                                                                          In both cases the only connection either RasPi has is an ethernet

                                                                          connection, no USB, no HDMI, absolutely nothing but the power supply.

                                                                          So if anyone else gets the ethernet dropout problem one of the possible

                                                                          causes can be the RasPi itself.  Of course in some cases it could be the

                                                                          power supply or any of the other diagnosis mentioned but the RasPi being

                                                                          the problem is a possibility.  I hope that helps.

                                                                          Good analysis -- very helpful to the community.

                                                                           

                                                                          Here are some of the things that could be happening with your flaky RasPi:

                                                                          1.  Poor contact of SD card connector.  However, if it always boots this is unlikely.

                                                                          2.  Iffy polyfuse F3.  As more current flows through F3, it gets warmer and increases resistance.  If it warms up too much, RasPi's 5V measured at TP1 goes too low and chips start to fail.

                                                                          3.  Iffy solder joint.  As the board heats up, it flexes slightly and the solder joint opens up.

                                                                          4.  Iffy PCB trace.  As the board heats up, it flexes slightly and the trace opens up.

                                                                           

                                                                          In most of these cases it's time for an RMA.

                                                                            • Re: Raspberry Pi loses ethernet
                                                                              etam89

                                                                              I had the same issue with RPI B and B+. I try 2A power supply, and it doesn't help. 

                                                                              I think it's Raspbian issue.   I also try updating FW, and roll back to old FW, and it doesn't help either. 

                                                                              I guess RPI foundation need to fix this backward compatibility issue.

                                                                                • Re: Raspberry Pi loses ethernet
                                                                                  John Beetem

                                                                                  Eugene Tam wrote:

                                                                                   

                                                                                  I had the same issue with RPI B and B+. I try 2A power supply, and it doesn't help.

                                                                                  I think it's Raspbian issue.   I also try updating FW, and roll back to old FW, and it doesn't help either.

                                                                                  I guess RPI foundation need to fix this backward compatibility issue.

                                                                                  Is the issue that RasPi runs for a long time and then fails, or does it not come up at all?  In the latter case, it could be an iffy Micro USB power cable.  A 2A supply doesn't help you if there's a significant drop over the power cable.  Check the RasPi's 5V level.

                                                                                   

                                                                                  There may be other useful suggestions at the RasPi Troubleshooting Wiki: http://elinux.org/R-Pi_Troubleshooting

                                                                                    • Re: Raspberry Pi loses ethernet
                                                                                      etam89

                                                                                      It takes less than 10 minutes to fail.  After a few minutes from Graphic is turned on, The pi first drops eth0, then it freeze 10 minutes after that.   If I stay with CLI after boot, then eth0 remains on indefinitely.  Thats with Raspbian Wheezy.

                                                                                       

                                                                                      I tried Jessie, but I experience the same issue with Eth0 - Pi drops Eth0.  But Graphic seems still running ... 1/2 hour now without any problem.

                                                                                       

                                                                                      Before, I can run programs on these Pi for months.  Something definitely messed up in the FW or Driver.  The problem is that I overwrote SD with the supposed newest and greatest recent Raspbian and can't revert back to the old FW/OS.

                                                                                       

                                                                                      Could anyone tell me which version of Raspbian does not have this problem?  At least, I can try to revert back to those version.

                                                                                       

                                                                                      I think the Foundation need to spend more time to clean up the FW/Driver instead to churning  more hardware.  The difference between RPI and other card is the RPI software.  Otherwise RPI users will turn to other cards. 

                                                                          • Re: Raspberry Pi loses ethernet
                                                                            netnut

                                                                            The power supply is fine. It can drive 2.1A, and I am running the same power supply in the same setup at a different location and things are fine.

                                                                            The differences between the two locations are:

                                                                            a) cable. I reused the cable that came with my Spark Core for the one that is not working correctly.

                                                                            b) router. cant believe that would be the issue

                                                                            c) temperature. the working Pi ambient is at 70F, the one that keeps halting ambient is 80+F. CPU temp, however, is at 55C well below the 85C Max.

                                                                             

                                                                            Here is a snippet from the pi halting. Without warning there is a shutdown at 04:26.44.

                                                                            Feb 23 04:25:01 rpiblr2 /USR/SBIN/CRON[7388]: (CRON) info (No MTA installed, discarding output)

                                                                            Feb 23 04:26:44 rpiblr2 shutdown[7400]: shutting down for system halt

                                                                            Feb 23 04:26:44 rpiblr2 init: Switching to runlevel: 0

                                                                            Feb 23 04:26:45 rpiblr2 ifplugd(eth0)[1586]: Exiting.

                                                                            Feb 23 04:26:47 rpiblr2 ifplugd(lo)[1552]: Exiting.

                                                                            Feb 23 04:26:47 rpiblr2 ntpd[2006]: ntpd exiting on signal 15

                                                                            Feb 23 04:26:59 rpiblr2 kernel: imklog 5.8.11, log source = /proc/kmsg started.

                                                                            Feb 23 04:26:59 rpiblr2 rsyslogd: [origin software="rsyslogd" swVersion="5.8.11" x-pid="1825" x-info="http://www.rsyslog.com"] start

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] Booting Linux on physical CPU 0x0

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] Initializing cgroup subsys cpu

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] Initializing cgroup subsys cpuacct

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] Linux version 3.10.25+ (dc4@dc4-arm-01) (gcc version 4.7.2 20120731 (prerelease) (crosstool-NG linaro-1.13.1+bzr2458 - Linaro GCC 2012.08) ) #622 PREEMPT Fri Jan 3 18:41:00 GMT 2014

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] CPU: ARMv6-compatible processor [410fb767] revision 7 (ARMv7), cr=00c5387d

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] CPU: PIPT / VIPT nonaliasing data cache, VIPT nonaliasing instruction cache

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] Machine: BCM2708

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] cma: CMA: reserved 16 MiB at 1b000000

                                                                             

                                                                            Would there be a clue in /var/log/debug ?

                                                                            This is what it says, and seems to be exactly when the Pi goes down:

                                                                            Feb 20 01:45:25 rpiblr2 kernel: [    1.962874] Module dwc_common_port init

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    0.000000] On node 0 totalpages: 114688

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    0.000000] free_area_init_node: node 0, pgdat c05cfd6c, node_mem_map c067d000

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    0.000000]   Normal zone: 896 pages used for memmap

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    0.000000]   Normal zone: 0 pages reserved

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    0.000000]   Normal zone: 114688 pages, LIFO batch:31

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    0.000000] pcpu-alloc: s0 r0 d32768 u32768 alloc=1*32768

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    0.000000] pcpu-alloc: [0] 0

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    1.874156] dwc_otg: Microframe scheduler enabled

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    1.963169] dwc_otg: FIQ enabled

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    1.963189] dwc_otg: NAK holdoff enabled

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    1.963200] dwc_otg: FIQ split fix enabled

                                                                            Feb 21 07:09:45 rpiblr2 kernel: [    1.963220] Module dwc_common_port init

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] On node 0 totalpages: 114688

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] free_area_init_node: node 0, pgdat c05cfd6c, node_mem_map c067d000

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000]   Normal zone: 896 pages used for memmap

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000]   Normal zone: 0 pages reserved

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000]   Normal zone: 114688 pages, LIFO batch:31

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] pcpu-alloc: s0 r0 d32768 u32768 alloc=1*32768

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    0.000000] pcpu-alloc: [0] 0

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    1.873554] dwc_otg: Microframe scheduler enabled

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    1.962694] dwc_otg: FIQ enabled

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    1.962713] dwc_otg: NAK holdoff enabled

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    1.962723] dwc_otg: FIQ split fix enabled

                                                                            Feb 23 04:26:59 rpiblr2 kernel: [    1.962744] Module dwc_common_port init

                                                  • Re: Raspberry Pi loses ethernet
                                                    obcd

                                                    It probably aren't cold solder joints. Lead free solderings look different than ordinary ones.

                                                    I have read about problems with the solderings of one of the xtals (X1 or X2) Due to that the oscillator sometimes stops.

                                                    If you would have a keyboard and screen connected, you might be able to check the logfiles for abnormallities.

                                                    I assume you already tried another ethernet cable to rule that out. Connecting to another ethernet port might be worth testing as well.

                                                    • Re: Raspberry Pi loses ethernet
                                                      iceman358

                                                      I found out that every loss of networking occurs when my router does a NTP Date/Time update and afterwards sends an ACK to the raspberry. It does not happen immediately after the NTP update, but when the ACK is sent. I do not know much about routers, but have managed to "solve" it by resetting both the router and the raspberry at the same time. My router is a very old piece of equipment of Pirelli ( ! ).

                                                       

                                                      Just putting it here if anyone has any thoughts on the matter.

                                                      • Re: Raspberry Pi loses ethernet
                                                        herseyj

                                                        I've had a similar experience when using a power supply which wasn't the best quality.  If you have another power supply kicking around which is over 700mA I would give that a shot before diving into the troubleshooting process to deeply.

                                                        • Re: Raspberry Pi loses ethernet
                                                          tobiz

                                                          Ok, I've now run my old RasPi with the SD card built on the new failing one and powered the old one by the new power supply, result - no ethernet dropout after running for about 4 hours (the new RasPi fails in about 4 mins).  I think I've now established to my satisfaction that there is something seriously wrong with my new RasPi and there is no other unit, power supply, SD card, ethernet router, ethernet cables etc etc that is the problem. 

                                                          In both cases the only connection to either RasPi is an ethernet connection, no USB, no HDMI, absolutely nothing but the power supply.  So if anyone else gets the ethernet dropout problem one of the possible causes can be the RasPi itself.  Of course in some cases it could be the power supply or any of the other diagnosis mentioned in this thread but the RasPi being the problem is a possibility.  I hope that helps.

                                                          • Re: Raspberry Pi loses ethernet
                                                            danringer

                                                            I've had the same problem but only with wifi usb dongles, I've found the ethernet jack to be extremely stable. Try newest os and a higher output power supply.  Maybe a heat sink?