This bug is missing log files that will aid in diagnosing the problem. While running an Ubuntu kernel (not a mainline or third-party kernel) please enter the following command in a terminal window:
apport-collect 1794169 and then change the status of the bug to 'Confirmed'. If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'. This change has been made by an automated script, maintained by the Ubuntu Kernel Team. ** Changed in: linux (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1794169 Title: AWS ubuntu became unreachable after ssh login Status in linux package in Ubuntu: Incomplete Status in systemd package in Ubuntu: New Bug description: I've reached strange situation with Ubuntu 18.04 LTS with latest kernel on AWS m5.xlarge instance. System became unreachable after series of successful ssh logins. systemd -user became zombie and block main systemd daemon (PID 1). I've created bug https://github.com/systemd/systemd/issues/10123 but it was closed with "there's a problem with your kernel". https://github.com/systemd/systemd/issues/10123#issuecomment-423984751 Symptoms are very similar to https://github.com/systemd/systemd/issues/8598 apetren+ 26679 0.0 0.0 0 0 ? Z 02:56 0:00 \_ [(sd-pam)] <defunct> apetren+ 26855 0.0 0.0 76636 7816 ? Ds 02:57 0:00 /lib/systemd/systemd --user apetren+ 26856 0.0 0.0 0 0 ? Z 02:57 0:00 \_ [(sd-pam)] <defunct> apetren+ 26954 0.0 0.0 0 0 ? Zs 02:57 0:00 \_ [kill] <defunct> apetren+ 27053 0.0 0.0 76636 7496 ? Ss 02:58 0:00 /lib/systemd/systemd --user apetren+ 27054 0.0 0.0 193972 2768 ? S 02:58 0:00 \_ (sd-pam) This situation is repeatable on 7 instances 1-2 times per week. how to repeat: 1. Install ubuntu 18.04 LTS from official ubuntu image 2. update kernel and packages to latest version 3. from another instance run while `true` ;do ssh ubu...@your.instance.ip "hostname; ps -ef|grep defunc |grep -v grep" ; done By this command in couple of days I have 2->4->6->8... zombies and in a hour system is frozen... sudo reboot is not working, because systemd with PID 1 is unreachable. kill -9 1 -- not working as well. # uname -r: Linux mainframe04 4.15.0-1021-aws #21-Ubuntu SMP Tue Aug 28 10:23:07 UTC 2018 x86_64 x86_64 x86_64 GNU/Linux # cat /etc/lsb-release DISTRIB_ID=Ubuntu DISTRIB_RELEASE=18.04 DISTRIB_CODENAME=bionic DISTRIB_DESCRIPTION="Ubuntu 18.04.1 LTS" # systemd --version systemd 237 +PAM +AUDIT +SELINUX +IMA +APPARMOR +SMACK +SYSVINIT +UTMP +LIBCRYPTSETUP +GCRYPT +GNUTLS +ACL +XZ +LZ4 +SECCOMP +BLKID +ELFUTILS +KMOD -IDN2 +IDN -PCRE2 default-hierarchy=hybrid AWS instance m5.xlarge Please let me know if you need any information. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1794169/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp