This bug was fixed in the package klibc - 2.0.4-8ubuntu3.1 --------------- klibc (2.0.4-8ubuntu3.1) yakkety; urgency=medium
* debian/patches/dhcp-one-socket-per-interface.patch: Use separate sockets for DHCP from multiple interfaces. Thanks to Jay Vosburgh <jay.vosbu...@canonical.com>. Closes LP: #1652348. -- Steve Langasek <steve.langa...@ubuntu.com> Tue, 24 Jan 2017 11:38:13 -0800 ** Changed in: klibc (Ubuntu Yakkety) Status: Fix Committed => Fix Released -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to klibc in Ubuntu. https://bugs.launchpad.net/bugs/1652348 Title: initrd dhcp fails / ignores valid response Status in klibc package in Ubuntu: Fix Released Status in klibc source package in Trusty: Fix Committed Status in klibc source package in Xenial: Fix Released Status in klibc source package in Yakkety: Fix Released Status in klibc source package in Zesty: Fix Released Bug description: [SRU justification] Changes to ordering of kernel enumeration of network interfaces, which may happen in any release, can regress network configuration from an initramfs. Support for netbooting should not depend on interface order, it should work reliably on all systems. [Test case] Detailed reproducer described in <https://bugs.launchpad.net/ubuntu/+source/klibc/+bug/1652348/comments/35>. [Regression potential] Moderate regression potential, because of a relatively large patch touching a not-widely-used but still critical piece of code. Regression testing should include verifying that MAAS-booted cloud images still work as expected in a variety of environments. Between kernel versions 4.4.0-53 and 4.4.0-57 a bug has been (re?)introduced that is breaking dhcp booting in the initrd environment. This is stopping instances that use iscsi storage from being able to connect. Over serial console it outputs: IP-Config: no response after 2 secs - giving up IP-Config: ens2f0 hardware address 90:e2:ba:d1:36:38 mtu 1500 DHCP RARP IP-Config: ens2f1 hardware address 90:e2:ba:d1:36:39 mtu 1500 DHCP RARP IP-Config: no response after 3 secs - giving up with increasing delays until it fails. At which point a simple ipconfig -t dhcp -d "ens2f0" works. The console output is slightly garbled but should give you an idea: (initramfs) ipconfig -t dhcp -[ 728.379793] ixgbe 0000:13:00.0 ens2f0: changing MTU from 1500 to 9000 d "ens2f0" IP-Config: ens2f0 hardware address 90:e2:ba:d1:36:38 mtu 1500 DHCP RARP IP-Config: ens2f0 guessed broadcast address 10.0.1.255 IP-Config: ens2f0 complete (dhcp from 169.254.169.254): addres[ 728.980448] ixgbe 0000:13:00.0 ens2f0: detected SFP+: 3 s: 10.0.1.56 broadcast: 10.0.1.255 netmask: 255.255.255.0 gateway: 10.0.1.1 [ 729.148410] ixgbe 0000:13:00.0 ens2f0: NIC Link is Up 10 Gbps, Flow Control: RX/TX dns0 : 169.254.169.254 dns1 : 0.0.0.0 rootserver: 169.254.169.254 rootpath: filename : /ipxe.efi tcpdumps show that dhcp requests are being received from the host, and responses sent, but not accepted by the host. When the ipconfig command is issued manually, an identical dhcp request and response happens, only this time it is accepted. It doesn't appear to be that the messages are being sent and received incorrectly, just silently ignored by ipconfig. I was seeing this behaviour earlier this year, which I was able to fix by specifying "ip=dhcp" as a kernel parameter. About a month ago that was identified as causing us other problems (long story) and we dropped it, at which point we discovered the original bug was no longer an issue. Putting "ip=dhcp" back on with this kernel no longer fixes the problem. I've compared the two initrds and effectively the only thing that has changed between the two is the kernel components. Ubuntu kernel bisect offending commit: # first bad commit: [fd4b5fa6e3487d15ede746f92601af008b2abbc0] mnt: Add a per mount namespace limit on the number of mounts Ubuntu kernel bisect offending commit submission: https://lkml.org/lkml/2016/10/5/308 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/klibc/+bug/1652348/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp