我在Hyper-V上运行Debian 8 vm（Win Srv 2012R2），当我做了稳定的升级时，我失去了所有的networking连接。 使用控制台，我能够看到networking接口为UP，但无法ping任何外部地址。
dist-upgrade将内核升级到了linux-image-3.16.0-4-686-pae（3.16.7-ckt11-1 + deb8u2）。
我能够通过添加2个传统的networking接口来解决这个问题，这个networking接口被这个新的内核所识别，但是性能却大大降低了。
Hyper-V模块似乎被加载得很好：
root@rproxy3:~# lsmod | fgrep hv_ hv_utils 17454 0 hv_netvsc 30069 0 hv_storvsc 17048 2 hv_vmbus 27978 6 hyperv_keyboard,hv_netvsc,hid_hyperv,hv_utils,hyperv_fb,hv_storvsc scsi_mod 164132 5 sg,libata,sd_mod,sr_mod,hv_storvsc root@rproxy3:~# dmesg | fgrep hv_ [ 1.303529] hv_vmbus: Hyper-V Host Build:9200-6.2-16-0.16729; Vmbus version:2.4 [ 1.336977] hv_vmbus: registering driver hv_storvsc [ 1.343214] hv_vmbus: registering driver hid_hyperv [ 1.344921] hv_vmbus: registering driver hv_netvsc [ 1.345790] hv_netvsc: hv_netvsc channel opened successfully [ 1.359193] hv_netvsc: hv_netvsc channel opened successfully [ 2.644921] hv_netvsc vmbus_0_13: Send section size: 6144, Section count:170 [ 2.645032] hv_netvsc vmbus_0_13: Device MAC 00:15:5d:01:56:1c link state down [ 3.060851] hv_netvsc vmbus_0_11: Send section size: 6144, Section count:170 [ 3.061034] hv_netvsc vmbus_0_11: Device MAC 00:15:5d:01:56:1b link state down [ 7.672833] hv_vmbus: registering driver hyperv_fb [ 7.893312] hv_vmbus: registering driver hyperv_keyboard [ 8.071484] hv_utils: Registering HyperV Utility Driver [ 8.071487] hv_vmbus: registering driver hv_util 但只有2个传统网卡被检测到（我configuration了2个传统网卡和2个合成网卡）：
root@rproxy3:~# dmesg | fgrep eth [ 1.351882] net eth0: Digital DS21140 Tulip rev 32 at Port 0xe880, 00:15:5d:01:56:1e, IRQ 9 [ 1.503780] net eth1: Digital DS21140 Tulip rev 32 at Port 0xec00, 00:15:5d:01:56:1f, IRQ 9 [ 11.628988] net eth0: Using EEPROM-set media 100baseTx-FDX [ 11.733151] net eth1: Using EEPROM-set media 100baseTx-FDX
任何想法如何进一步debugging呢？