After discussion on IRC and some additional investigations, it seems like what's happening is that stderr is being closed at some point during the update-motd process. If stderr is closed, then lsb_release can exit with a non-zero status, and this will cause check-new-release to try to write to stderr, which will cause the IOError if it's closed.
It's not entirely clear to us why or how stderr can get closed, and no one here has been able to reproduce the problem. However, we have a possible workaround. If you are having the problem, please try the attached patch and see if that fixes the bug. If so, we'll get this into saucy and SRU it into stable releases. Note this is only a workaround, but after discussion with Colin, and in the absence of a reproducer or more information, it's probably still reasonable to apply this. You may need to apply this diff to /etc /update-motd.d/91-release-upgrade ** Patch added: "motd.diff" https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/982082/+attachment/3696615/+files/motd.diff ** Changed in: ubuntu-release-upgrader (Ubuntu) Status: Triaged => Incomplete ** Changed in: ubuntu-release-upgrader (Ubuntu) Assignee: (unassigned) => Barry Warsaw (barry) -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/982082 Title: do-release-upgrade crashed with IOError in init_proxy(): [Errno 5] Input/output error To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/982082/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
