I got the same problem on upgrading from 14.04 to 14.10.
On dmesg I see:
[ 43.323648] systemd-logind[2817]: Failed to start unit user@111.service: Unknown unit: user@111.service
[ 43.323654] systemd-logind[2817]: Failed to start user service: Unknown unit: user@111.service
[ 43.326729] systemd-logind[2817]: New session c1 of user lightdm.
[ 43.326748] systemd-logind[2817]: Linked /tmp/.X11-unix/X0 to /run/user/111/X11-display.
[ 44.387104] init: plymouth-stop pre-start process (4632) terminated with status 1
[ 57.998337] audit: type=1400 audit(1414195441.914:38): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="/usr/lib/cups/backend/cups-pdf" pid=4840 comm="apparmor_parser"
[ 57.998349] audit: type=1400 audit(1414195441.914:39): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="/usr/sbin/cupsd" pid=4840 comm="apparmor_parser"
[ 58.011666] audit: type=1400 audit(1414195441.930:40): apparmor="STATUS" operation="profile_replace" profile="unconfined" name="third_party" pid=4840 comm="apparmor_parser"
[ 67.951030] systemd-logind[2817]: Failed to start unit user@1000.service: Unknown unit: user@1000.service
[ 67.951036] systemd-logind[2817]: Failed to start user service: Unknown unit: user@1000.service
[ 67.953605] systemd-logind[2817]: New session 1 of user ldavim.
[ 67.953621] systemd-logind[2817]: Linked /tmp/.X11-unix/X0 to /run/user/1000/X11-display.
[ 67.956202] systemd-logind[2817]: Existing logind session ID 1 used by new audit session, ignoring
[ 67.958750] systemd-logind[2817]: New session c2 of user ldavim.
[ 76.073380] init: anacron main process (3189) killed by TERM signal
I got the same problem on upgrading from 14.04 to 14.10.
On dmesg I see:
[ 43.323648] systemd- logind[ 2817]: Failed to start unit user@111.service: Unknown unit: user@111.service logind[ 2817]: Failed to start user service: Unknown unit: user@111.service logind[ 2817]: New session c1 of user lightdm. logind[ 2817]: Linked /tmp/.X11-unix/X0 to /run/user/ 111/X11- display. 1.914:38) : apparmor="STATUS" operation= "profile_ replace" profile= "unconfined" name="/ usr/lib/ cups/backend/ cups-pdf" pid=4840 comm="apparmor_ parser" 1.914:39) : apparmor="STATUS" operation= "profile_ replace" profile= "unconfined" name="/ usr/sbin/ cupsd" pid=4840 comm="apparmor_ parser" 1.930:40) : apparmor="STATUS" operation= "profile_ replace" profile= "unconfined" name="third_party" pid=4840 comm="apparmor_ parser" logind[ 2817]: Failed to start unit user@1000.service: Unknown unit: user@1000.service logind[ 2817]: Failed to start user service: Unknown unit: user@1000.service logind[ 2817]: New session 1 of user ldavim. logind[ 2817]: Linked /tmp/.X11-unix/X0 to /run/user/ 1000/X11- display. logind[ 2817]: Existing logind session ID 1 used by new audit session, ignoring logind[ 2817]: New session c2 of user ldavim.
[ 43.323654] systemd-
[ 43.326729] systemd-
[ 43.326748] systemd-
[ 44.387104] init: plymouth-stop pre-start process (4632) terminated with status 1
[ 57.998337] audit: type=1400 audit(141419544
[ 57.998349] audit: type=1400 audit(141419544
[ 58.011666] audit: type=1400 audit(141419544
[ 67.951030] systemd-
[ 67.951036] systemd-
[ 67.953605] systemd-
[ 67.953621] systemd-
[ 67.956202] systemd-
[ 67.958750] systemd-
[ 76.073380] init: anacron main process (3189) killed by TERM signal