From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Kent Subject: Re: Suggestion for better manpage. Date: Tue, 17 Jun 2008 20:13:56 +0800 Message-ID: <1213704836.20728.10.camel@raven.themaw.net> References: <200806171257.45914.stef@bononline.nl> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <200806171257.45914.stef@bononline.nl> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: autofs-bounces@linux.kernel.org Errors-To: autofs-bounces@linux.kernel.org To: Stef Bon Cc: autofs mailing list On Tue, 2008-06-17 at 12:57 +0200, Stef Bon wrote: > Hello, > > reading the manpage of automount, I would like to change the section in the > manpage about how the daemon reacts on signals. Send a patch. > > It is now: > > > If the automount daemon catches a USR1 signal, it will umount all > currently unused autofs managed mounted file systems and continue running > (forced expire). If it catches the TERM signal it will umount all > unused autofs managed mounted file systems and exit if there are no > remaining > busy file systems. If autofs has been compiled with the option to > ignore busy mounts on exit it will exit leaving any busy mounts in place > other- > wise busy file systems will not be umounted and autofs will not exit. > Alternatively, if autofs has been compiled with the option to enable forced > shutdown then a USR2 signal to the daemon will cause all mounts to be > umounted and any busy mounts to be forcibly umounted, including autofs mount > point directories (summary execution). Note that the forced umount is > an unlink operation and the actual umount will not happen in the kernel un- > til active file handles are released. The daemon also responds to a > HUP signal which triggers an update of the maps for each mount point. > > If any autofs mount point directories are busy when the daemon is sent > an exit signal the daemon will not exit. The exception to this is if autofs > has been built with configure options to either ignore busy mounts at > exit or force umount at exit. If the ignore busy mounts at exit option is > used the filesystems will be left in a catatonic (non-functional) > state and can be manually umounted when they become unused. If the force > umount > at exit option is used the filesystems will be umounted but the mount > will not be released by the kernel until they are no longer in use by the > processes that held them busy. If automount managed filesystems are > found mounted when autofs is started they will be recoverd unless they are no > longer present in the map in which case they need to umounted manually. > > I would like to suggest: > > The automount daemon can react on a few signals. Some of them are standard, > others are less standard and/or need compiletime options. > > TERM > > If it catches the TERM signal it will umount all unused autofs managed mounted > filesystems, and exit if there are no remaining mounts left. It will keep on > running (till??) You eventually send a TERM signal and no mounts are in use. > If compiled with the "ignore busy mounts" option, it will exit here, and leave > any mountpoint in place. > > USR2 > This only applies when the automounter is compiled with the "enable forced > shudown". When it catches the USR2, it will umount all mounts, busy or not. > Note: umounting a busy mountpoint is actually an unlink operation. The actual > umount will be done later, when all active file handleds are released. (this > id done by??) Kernel. > > USR1 > With the USR1 signal it will umount all currently unused mounts, and continue > running (forced expire). > > HUP > This signal triggers an update of the maps for each mountpoint. > > > I've left out some parts, but mostly rearranged the information. I've left > out the text "summary execution" Is it important? > > But what do you think. Is it better this way? > > Stef Bon > > _______________________________________________ > autofs mailing list > autofs@linux.kernel.org > http://linux.kernel.org/mailman/listinfo/autofs