1.\" Copyright (c) 2007 The DragonFly Project. All rights reserved. 2.\" 3.\" This code is derived from software contributed to The DragonFly Project 4.\" by Matthew Dillon <dillon@backplane.com> 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in 14.\" the documentation and/or other materials provided with the 15.\" distribution. 16.\" 3. Neither the name of The DragonFly Project nor the names of its 17.\" contributors may be used to endorse or promote products derived 18.\" from this software without specific, prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 21.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22.\" LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23.\" FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 24.\" COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25.\" INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 26.\" BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 27.\" LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28.\" AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29.\" OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 30.\" OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31.\" SUCH DAMAGE. 32.\" 33.Dd December 31, 2015 34.Dt MOUNT_HAMMER 8 35.Os 36.Sh NAME 37.Nm mount_hammer 38.Nd mount a HAMMER file system 39.Sh SYNOPSIS 40.Nm 41.Op Fl o Ar options 42.Op Fl T Ar transaction-id 43.Ar special ... 44.Ar node 45.Nm 46.Op Fl o Ar options 47.Op Fl T Ar transaction-id 48.Ar special Ns Oo Cm \&: Ns Ar special Oc Ns * 49.Ar node 50.Nm 51.Fl u 52.Op Fl o Ar options 53.Ar node 54.Sh DESCRIPTION 55The 56.Nm 57utility mounts a 58.Nm HAMMER 59file system backed by 60.Ar special 61file(s) at mount point 62.Ar node . 63.Pp 64The options are as follows: 65.Bl -tag -width indent 66.It Fl o Ar options 67Options are specified with a 68.Fl o 69flag followed by a comma separated string of options. 70See the 71.Xr mount 8 72man page for possible options and their meanings. 73The following 74.Nm HAMMER 75specific options are also available: 76.Bl -tag -width indent 77.It Cm nohistory 78Put the entire file system in no-history mode. 79Change history is not retained. 80Use of this option may increase the overhead of doing mirroring. 81This option is generally only used in an emergency. 82.It Cm master= Ns Ar id 83Assign a master id for the entire mount which applies to all PFSs under 84the mount. 85This is intended to help support multi-master and fail-over operation. 86Multi-master operation is not yet supported. 87If you intend 88to upgrade slaves to masters and downgrade masters to slaves as part of 89a fail-over setup, it's a good idea to assign a different master id 90to the 91.Nm HAMMER 92mounts making up the fail-over group. 93.It Cm nomirror 94By default a 95.Nm HAMMER 96mount assigns a master id of 0. 97You can force no-mirror operation by specifying this option. 98This option disables 99mirror transaction id propagation in the B-Tree and will improve write 100performance somewhat but also prevents incremental mirroring from working 101at all, and is not recommended. 102.El 103.It Fl T Ar transaction-id 104Mount the file system as-of a particular 105transaction id. 106The mount will automatically be made read-only. 107The 108.Ar transaction-id 109must be specified as a 64 bit hex value prefixed with "0x". 110.It Fl u 111Update the mount point. 112This is typically used to upgrade a mount to 113read-write or downgrade it to read-only. 114.El 115.Sh NOTES 116Note that issuing a read-only mount which requires UNDOs to be run will 117still run the UNDOs, but will not flush the buffer cache buffers until/if 118the mount is updated to read-write. 119.Sh EXIT STATUS 120.Ex -std 121.Sh EXAMPLES 122Mount a 123.Nm HAMMER 124file system made up of two volumes onto 125.Pa /mnt : 126.Bd -literal -offset indent 127mount_hammer -o ro,noatime /dev/ad0s1d /dev/ad1s1d /mnt 128.Ed 129.Pp 130Above is equivalent to below using blkdevs format for 131.Nm HAMMER 132volumes as 133.Nm 134supports both formats. 135.Bd -literal -offset indent 136mount_hammer -o ro,noatime /dev/ad0s1d:/dev/ad1s1d /mnt 137.Ed 138.Pp 139A corresponding 140.Xr fstab 5 141entry is: 142.Bd -literal -offset indent 143/dev/ad0s1d:/dev/ad1s1d /mnt hammer ro,noatime 144.Ed 145.Sh SEE ALSO 146.Xr mount 2 , 147.Xr unmount 2 , 148.Xr fstab 5 , 149.Xr HAMMER 5 , 150.Xr disklabel 8 , 151.Xr disklabel64 8 , 152.Xr fdisk 8 , 153.Xr gpt 8 , 154.Xr hammer 8 , 155.Xr mount 8 , 156.Xr newfs_hammer 8 157.Sh HISTORY 158The 159.Nm 160utility first appeared in 161.Dx 1.11 . 162.Sh AUTHORS 163.An Matthew Dillon Aq Mt dillon@backplane.com 164