I'm using raring and also having the issue of shutdown/restart hanging for a short time due to "mount: / is busy".
I made a script that executes "ps -Af" on shutdown/reboot and writes it to a log file. (see attachment) There's a long line containing "/sbin/dhclient"; I presume that indicates dhclient being the root cause? ** Attachment added: "log file of ps -Af during shutdown/reboot" https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1169614/+attachment/3743585/+files/process.log -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to network-manager in Ubuntu. https://bugs.launchpad.net/bugs/1169614 Title: /etc/init.d/umountroot: "mount: / is busy" due to dhclient is not stopped Status in “network-manager” package in Ubuntu: Confirmed Bug description: The result is "mount: / is busy" and root filesystem recovery during next boot. network-manager 0.9.8.0-0ubuntu3 in Raring neither stop dhclient in response to "stop network-manager" nor remove pid file from /run/sendsigs.omit.d/ So dhclient skipped by /etc/init.d/sendsigs and a lease file is open for writing in /var/lib/NetworkManager while /etc/init.d/umountroot is running. As a consequence root filesystem can not be cleanly remount readonly before poweroff. In default setup the problem is hidden by plymouth. The problem does not appear if network is disabled or the cable is unplugged before shutdown. There are some other bugs that might be caused by this issue: Bug lp: #1073433 Ext4 corruption associated with shutdown of Ubuntu 12.10 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/1169614/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp
