It does not seem to affect lighttpd. Journalctl did output following when it happened last time:
syys 12 22:03:41 sipuli dhclient[3111]: PRC: Renewing lease on wlp2s0b1. syys 12 22:03:41 sipuli dhclient[3111]: XMT: Renew on wlp2s0b1, interval 9430ms. syys 12 22:03:41 sipuli dhclient[3111]: RCV: Reply message on wlp2s0b1 from fe80::924e:2bff:fe5b:9c6e. syys 12 22:03:41 sipuli NetworkManager[2495]: <info> [1473707021.3234] valid_lft 7200 syys 12 22:03:41 sipuli NetworkManager[2495]: <info> [1473707021.3235] preferred_lft 3600 syys 12 22:03:41 sipuli NetworkManager[2495]: <info> [1473707021.3236] address 2001:14bb:170:83bf::6 syys 12 22:03:41 sipuli NetworkManager[2495]: <info> [1473707021.3236] nameserver 'fe80::924e:2bff:fe5b:9c6e' syys 12 22:03:41 sipuli NetworkManager[2495]: <info> [1473707021.3237] dhcp6 (wlp2s0b1): state changed bound -> boun syys 12 22:03:41 sipuli dbus[2491]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' uni syys 12 22:03:41 sipuli systemd[1]: Starting Network Manager Script Dispatcher Service... syys 12 22:03:41 sipuli dbus[2491]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher' syys 12 22:03:41 sipuli systemd[1]: Started Network Manager Script Dispatcher Service. syys 12 22:03:41 sipuli nm-dispatcher[23149]: req:1 'dhcp6-change' [wlp2s0b1]: new request (1 scripts) syys 12 22:03:41 sipuli nm-dispatcher[23149]: req:1 'dhcp6-change' [wlp2s0b1]: start running ordered scripts... syys 12 22:17:01 sipuli CRON[23324]: pam_unix(cron:session): session opened for user root by (uid=0) syys 12 22:17:01 sipuli CRON[23325]: (root) CMD ( cd / && run-parts --report /etc/cron.hourly) syys 12 22:17:01 sipuli CRON[23324]: pam_unix(cron:session): session closed for user root syys 12 22:17:33 sipuli unix_chkpwd[23333]: password check failed for user (il) syys 12 22:17:33 sipuli compiz[3410]: pam_unix(unity:auth): authentication failure; logname= uid=1000 euid=1000 tty= syys 12 22:17:39 sipuli compiz[3410]: pam_ecryptfs: seteuid error syys 12 22:17:39 sipuli compiz[3410]: gkr-pam: unlocked login keyring syys 12 22:18:59 sipuli systemd[1]: Started CUPS Scheduler. syys 12 22:19:12 sipuli dbus[2491]: [system] Activating via systemd: service name='org.freedesktop.hostname1' unit='d syys 12 22:19:12 sipuli systemd[1]: Starting Hostname Service... syys 12 22:19:13 sipuli dbus[2491]: [system] Successfully activated service 'org.freedesktop.hostname1' syys 12 22:19:13 sipuli systemd[1]: Started Hostname Service. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1622707 Title: CUPS Web UI stops responding after a while To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cups/+bug/1622707/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs