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diff --git a/upstream/fedora-rawhide/man8/nfsdcltrack.8 b/upstream/fedora-rawhide/man8/nfsdcltrack.8 new file mode 100644 index 00000000..3905ba46 --- /dev/null +++ b/upstream/fedora-rawhide/man8/nfsdcltrack.8 @@ -0,0 +1,112 @@ +.ie \nF \{\ +. de IX +. tm Index:\\$1\t\\n%\t"\\$2" +.. +. nr % 0 +. rr F +.\} +.el \{\ +. de IX +.. +.\} +.IX Title "NFSDCLTRACK 8" +.TH NFSDCLTRACK 8 "2012-10-24" "" "" +.\" For nroff, turn off justification. Always turn off hyphenation; it makes +.\" way too many mistakes in technical documents. +.if n .ad l +.nh +.SH "NAME" +nfsdcltrack \- NFSv4 Client Tracking Callout Program +.SH "SYNOPSIS" +.IX Header "SYNOPSIS" +nfsdcltrack [\-d] [\-f] [\-s stable storage dir] <command> <args...> +.SH "DESCRIPTION" +.IX Header "DESCRIPTION" +nfsdcltrack is the NFSv4 client tracking callout program. It is not necessary +to install this program on machines that are not acting as NFSv4 servers. +.PP +When a network partition is combined with a server reboot, there are +edge conditions that can cause the server to grant lock reclaims when +other clients have taken conflicting locks in the interim. A more detailed +explanation of this issue is described in \s-1RFC\s0 3530, section 8.6.3 +and in \s-1RFC\s0 5661, section 8.4.3. +.PP +In order to prevent these problems, the server must track a small amount +of per-client information on stable storage. This program provides the +userspace piece of that functionality. When the kernel needs to manipulate +the database that stores this info, it will execute this program to handle +it. +.SH "OPTIONS" +.IX Header "OPTIONS" +.IP "\fB\-d\fR, \fB\-\-debug\fR" 4 +.IX Item "-d, --debug" +Enable debug level logging. +.IP "\fB\-f\fR, \fB\-\-foreground\fR" 4 +.IX Item "-f, --foreground" +Log to stderr instead of syslog. +.IP "\fB\-s\fR \fIstoragedir\fR, \fB\-\-storagedir\fR=\fIstorage_dir\fR" 4 +.IX Item "-s storagedir, --storagedir=storage_dir" +Directory where stable storage information should be kept. The default +value is \fI/var/lib/nfs/nfsdcltrack\fR. +.SH "COMMANDS" +.IX Header "COMMANDS" +nfsdcltrack requires a command for each invocation. Supported commands +are: +.IP "\fBinit\fR" 4 +.IX Item "init" +Initialize the database. This command requires no argument. +.IP "\fBcreate\fR" 4 +.IX Item "create" +Create a new client record (or update the timestamp on an existing one). This command requires a hex-encoded nfs_client_id4 as an argument. +.IP "\fBremove\fR" 4 +.IX Item "remove" +Remove a client record from the database. This command requires a hex-encoded nfs_client_id4 as an argument. +.IP "\fBcheck\fR" 4 +.IX Item "check" +Check to see if a nfs_client_id4 is allowed to reclaim. This command requires a hex-encoded nfs_client_id4 as an argument. +.IP "\fBgracedone\fR" 4 +.IX Item "gracedone" +Remove any unreclaimed client records from the database. This command requires a epoch boot time as an argument. +.SH "EXTERNAL CONFIGURATION" +The directory for stable storage information can be set via the file +.B /etc/nfs.conf +by setting the +.B storagedir +value in the +.B nfsdcltrack +section. For example: +.in +5 +[nfsdcltrack] +.br + storagedir = /shared/nfs/nfsdcltrack +.in -5 +Debugging to syslog can also be enabled by setting "debug = 1" in this file. +.SH "LEGACY TRANSITION MECHANISM" +.IX Header "LEGACY TRANSITION MECHANISM" +The Linux kernel NFSv4 server has historically tracked this information +on stable storage by manipulating information on the filesystem +directly, in the directory to which \fI/proc/fs/nfsd/nfsv4recoverydir\fR +points. If the kernel passes the correct information, then nfsdcltrack +can use it to allow a seamless transition from the old client tracking +scheme to the new one. +.PP +On a \fBcheck\fR operation, if there is no record of the client in the +database, nfsdcltrack will look to see if the \fB\s-1NFSDCLTRACK_LEGACY_RECDIR\s0\fR +environment variable is set. If it is, then it will fetch that value and +see if a directory exists by that name. If it does, then the check +operation will succeed and the directory will be removed. +.PP +On a \fBgracedone\fR operation, nfsdcltrack will look to see if the +\&\fB\s-1NFSDCLTRACK_LEGACY_TOPDIR\s0\fR environment variable is set. If it is, then +it will attempt to clean out that directory prior to exiting. +.PP +Note that this transition is one-way. If the machine subsequently reboots +back into an older kernel that does not support the nfsdcltrack upcall +then the clients will not be able to recover their state. +.SH "NOTES" +.IX Header "NOTES" +This program requires a kernel that supports the nfsdcltrack usermodehelper +upcall. This support was first added to mainline kernels in 3.8. +.SH "AUTHORS" +.IX Header "AUTHORS" +nfsdcltrack was developed by Jeff Layton <jlayton@redhat.com>. |