Found a time when I didn't mind rebooting, and tested tested linux-image-3.18.0-031800rc7-generic version 3.18.0-031800rc7.201411302035
peter@tesla:~$ uname -a Linux tesla 3.18.0-031800rc7-generic #201411302035 SMP Mon Dec 1 01:36:38 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux peter@tesla:~$ route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 10.0.0.1 0.0.0.0 UG 0 0 0 eth0 10.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 eth0 peter@tesla:~$ sudo ethtool -t eth0 offline The test result is FAIL The test extra info: Register test (offline) 0 Eeprom test (offline) 0 Interrupt test (offline) 0 Loopback test (offline) 0 Link test (on/offline) 1 peter@tesla:~$ route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 10.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 eth0 peter@tesla:~$ sudo route add default gw 10.0.0.1 peter@tesla:~$ route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 10.0.0.1 0.0.0.0 UG 0 0 0 eth0 10.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 eth0 dmesg (relevant section): [ 2039.585309] e1000e 0000:00:19.0 eth0: offline testing starting [ 2039.805954] e1000e: eth0 NIC Link is Down [ 2040.225964] e1000e 0000:00:19.0 eth0: testing unshared interrupt [ 2053.684783] e1000e 0000:00:19.0: irq 29 for MSI/MSI-X [ 2053.788074] e1000e 0000:00:19.0: irq 29 for MSI/MSI-X [ 2068.760891] e1000e: eth0 NIC Link is Up 10 Mbps Full Duplex, Flow Control: Rx/Tx [ 2068.761001] e1000e 0000:00:19.0 eth0: Link Speed was downgraded by SmartSpeed [ 2068.761004] e1000e 0000:00:19.0 eth0: 10/100 speed: disabling TSO So it takes about 18 seconds for my NIC to fall back to a 10baseT link to my gigabit switch. I think my switch may be dying, I've seen some issues on other machines, too. If anyone's interested in working on fixing this, you could simulate this by unplugging the ethernet cable as you press return on ethtool, and wait 10 secs to plug it back in. Or just ethtool -t offline with your cable unplugged, I guess. ** Tags added: e1000e kernel-bug-exists-upstream -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1395269 Title: [e1000e] ethtool -t eth0 offline loses routing table To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1395269/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
