I encountered the exact same issue with loss of network upgrading Ubuntu 12.04LTS 32-bit to 14.04LTS 32-bit on a Hyper-V VM (Windows 2008R2). I went through the same steps to do a fresh install of 14.04LTS 32-bit and had the same result. Also found Ubuntu 14.04LTS 64-bit worked well and did not experience this issue.
After much testing, I found that if I dropped the RAM of the Ubuntu 14.04LTS VM to 4014MB on 2008R2 Hyper-V (4026MB on Hyper-V 2012R2), the network adapter will show up and network connectivity will resume (Will have internal system errors however). I then dropped to 2048MB and Ubuntu is stable and network is connected. My Ubuntu 12.04LTS 32-bit VMs run 4GB wonderfully and never experienced issues with memory/networking. Also tested on different hosts and found this network issue is the same on Hyper-V versions 2008R2, 2012 and 2012R2 when memory is pushed to 4GB for the VMs. I tested Ubuntu 14.04LTS 32-bit on a physical machine with 4GB of RAM and system runs great, no network issues. The download of 14.04LTS 32-bit does display "for machines running 2GB or less". How much memory are you giving affected VMs? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1338185 Title: networking fails in 32-bit 14.04 using HyperV on Win2012R2 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1338185/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
