I get the unable to connect message about 10 secs after boot but no further lightdm messages, and no obvious ill effect, so perhaps it is unrelated to the PAM messages. In fact the only lightdm messages I see are:
$ grep -i lightdm /var/log/syslog
Apr 6 09:57:14 tigger kernel: [ 10.835217] audit: type=1400 audit(1428310634.471:2): apparmor="STATUS" operation="profile_load" profile="unconfined" name="/usr/lib/lightdm/lightdm-guest-session" pid=512 comm="apparmor_parser"
Apr 6 09:57:21 tigger lightdm[1449]: initctl: Unable to connect to Upstart: Failed to connect to socket /com/ubuntu/upstart: Connection refused
syslog contained the complete boot sequence, and more.
I get the unable to connect message about 10 secs after boot but no further lightdm messages, and no obvious ill effect, so perhaps it is unrelated to the PAM messages. In fact the only lightdm messages I see are:
$ grep -i lightdm /var/log/syslog 4.471:2) : apparmor="STATUS" operation= "profile_ load" profile= "unconfined" name="/ usr/lib/ lightdm/ lightdm- guest-session" pid=512 comm="apparmor_ parser" upstart: Connection refused
Apr 6 09:57:14 tigger kernel: [ 10.835217] audit: type=1400 audit(142831063
Apr 6 09:57:21 tigger lightdm[1449]: initctl: Unable to connect to Upstart: Failed to connect to socket /com/ubuntu/
syslog contained the complete boot sequence, and more.