xref: /freebsd/share/man/man4/iscsi.4 (revision 0e97acdf58fe27b09c4824a474b0344daf997c5f)
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25.\" $FreeBSD$
26.Dd September 11, 2014
27.Dt ISCSI 4
28.Os
29.Sh NAME
30.Nm iscsi
31.Nd iSCSI initiator
32.Sh SYNOPSIS
33To compile this driver into the kernel,
34place the following line in the
35kernel configuration file:
36.Bd -ragged -offset indent
37.Cd "device iscsi"
38.Ed
39.Pp
40Alternatively, to load the driver as a
41module at boot time, place the following line in
42.Xr loader.conf 5 :
43.Bd -literal -offset indent
44iscsi_load="YES"
45.Ed
46.Sh DESCRIPTION
47The
48.Nm
49subsystem provides the kernel component of an iSCSI initiator.
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 .
56The
57.Nm
58subsystem is responsible for implementing the
59.Qq Full Feature Phase
60of the iSCSI protocol.
61.Sh SYSCTL VARIABLES
62The following variables are available as both
63.Xr sysctl 8
64variables and
65.Xr loader 8
66tunables:
67.Bl -tag -width indent
68.It Va kern.iscsi.ping_timeout
69The number of seconds to wait for the target to respond to a NOP-Out
70PDU.
71In the event that there is no response within that time the session gets
72forcibly restarted.
73.It Va kern.iscsi.iscsid_timeout
74The number of seconds to wait for
75.Xr ctld 8
76to establish a session.
77After that time
78.Nm
79will abort and retry.
80.It Va kern.iscsi.login_timeout
81The number of seconds to wait for a login attempt to succeed.
82After that time
83.Nm
84will abort and retry.
85.It Va kern.iscsi.maxtags
86The maximum number of outstanding IO requests.
87.It Va kern.iscsi.fail_on_disconnection
88Controls the behavior after an iSCSI connection has been dropped due to
89network problems.
90When set to 1, a dropped connection causes the iSCSI device nodes
91to be destroyed.
92After reconnecting, they will be created again.
93By default, the device nodes are left intact.
94While the connection is down all input/output operations are suspended, to be
95retried after the connection is reestablished.
96.El
97.Sh SEE ALSO
98.Xr iscsi.conf 5 ,
99.Xr iscsictl 8 ,
100.Xr iscsid 8
101.Sh HISTORY
102The
103.Nm
104subsystem first appeared in
105.Fx 10.0 .
106.Sh AUTHORS
107The
108.Nm
109subsystem was developed by
110.An Edward Tomasz Napierala Aq Mt trasz@FreeBSD.org
111under sponsorship from the FreeBSD Foundation.
112