1.\" Copyright (c) 2014 Edward Tomasz Napierala 2.\" 3.\" Redistribution and use in source and binary forms, with or without 4.\" modification, are permitted provided that the following conditions 5.\" are met: 6.\" 1. Redistributions of source code must retain the above copyright 7.\" notice, this list of conditions and the following disclaimer. 8.\" 2. Redistributions in binary form must reproduce the above copyright 9.\" notice, this list of conditions and the following disclaimer in the 10.\" documentation and/or other materials provided with the distribution. 11.\" 12.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 13.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 14.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 15.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 16.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 17.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 18.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 19.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 20.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 21.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 22.\" SUCH DAMAGE. 23.\" 24.\" $FreeBSD$ 25.Dd May 28, 2017 26.Dt ISCSI 4 27.Os 28.Sh NAME 29.Nm iscsi 30.Nd iSCSI initiator 31.Sh SYNOPSIS 32To compile this driver into the kernel, 33place the following line in the 34kernel configuration file: 35.Bd -ragged -offset indent 36.Cd "device iscsi" 37.Ed 38.Pp 39Alternatively, to load the driver as a 40module at boot time, place the following line in 41.Xr loader.conf 5 : 42.Bd -literal -offset indent 43iscsi_load="YES" 44.Ed 45.Sh DESCRIPTION 46The 47.Nm 48subsystem provides the kernel component of an iSCSI initiator, 49responsible for implementing the Full Feature Phase of the iSCSI protocol. 50The initiator is the iSCSI client, which connects to an iSCSI target, 51providing local access to a remote block device. 52The userland component is provided by 53.Xr iscsid 8 54and both the kernel and userland are configured using 55.Xr iscsictl 8 . 56.Sh SYSCTL VARIABLES 57The following variables are available as both 58.Xr sysctl 8 59variables and 60.Xr loader 8 61tunables: 62.Bl -tag -width indent 63.It Va kern.iscsi.debug 64Verbosity level for log messages from the 65.Nm 66driver. 67Set to 0 to disable logging or 1 to warn about potential problems. 68Larger values enable debugging output. 69Defaults to 1. 70.It Va kern.iscsi.ping_timeout 71The number of seconds to wait for the target to respond to a NOP-Out 72PDU. 73In the event that there is no response within that time the session gets 74forcibly restarted. 75Set to 0 to disable sending NOP-Out PDUs. 76Defaults to 5. 77.It Va kern.iscsi.iscsid_timeout 78The number of seconds to wait for 79.Xr iscsid 8 80to establish a session. 81After that time 82.Nm 83will abort and retry. 84Defaults to 60. 85.It Va kern.iscsi.login_timeout 86The number of seconds to wait for a login attempt to succeed. 87After that time 88.Nm 89will abort and retry. 90Defaults to 60. 91.It Va kern.iscsi.maxtags 92The maximum number of outstanding IO requests. 93Defaults to 255. 94.It Va kern.iscsi.fail_on_disconnection 95Controls the behavior after an iSCSI connection has been dropped due to 96network problems. 97When set to 1, a dropped connection causes the iSCSI device nodes 98to be destroyed. 99After reconnecting, they will be created again. 100By default, the device nodes are left intact. 101While the connection is down all input/output operations are suspended, to be 102retried after the connection is reestablished. 103.El 104.Sh SEE ALSO 105.Xr iser 4 , 106.Xr iscsi.conf 5 , 107.Xr iscsictl 8 , 108.Xr iscsid 8 109.Sh HISTORY 110The 111.Nm 112subsystem first appeared in 113.Fx 10.0 . 114.Sh AUTHORS 115The 116.Nm 117subsystem was developed by 118.An Edward Tomasz Napierala Aq Mt trasz@FreeBSD.org 119under sponsorship from the FreeBSD Foundation. 120