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14 .Dd February 5, 2106
15 .Dt LX 5
16 .Os
17 .Sh NAME
18 .Nm lx
19 .Nd zone brand for running a GNU/Linux user-level environment
20 .Sh DESCRIPTION
21 The
22 .Em lx
23 brand
24 uses the
25 .Xr brands 5
26 framework to provide an environment for running binary applications built
27 for GNU/Linux. User-level code, including an entire Linux distribution, can
28 run inside the zone. Both 32-bit and 64-bit applications are supported. The
29 majority of Linux system calls are provided, along with emulation for a
30 variety of Linux file systems, such as
31 .Em proc ,
32 .Em cgroup
33 and
34 .Em sysfs .
35 .Pp
36 The
37 .Em /proc
38 file system within the zone is a subset of a full Linux
39 .Em /proc .
40 Most kernel-level tuning applied to
41 .Em /proc
42 is unavailable or ignored. Some tuning can be performed, but only to reduce
43 the overall limits that have been specified on the zone's configuration.
44 That is, within the zone there is no way to increase the resource limits set
45 on the zone itself.
46 .Pp
47 The zone must be installed using a clone of a
48 .Xr zfs 1m
49 dataset which contains an image of the software to be run in the zone.
50 .Pp
51 Example:
52 .Dl zoneadm -z myzone install -x nodataset -t debian7
53 .Pp
54 Applications provided by the base SunOS operating system are also available
55 within the zone under the
56 .Em /native
57 mount point. This allows the use of various native tools such as
58 .Xr dtrace 1m ,
59 .Xr mdb 1 ,
60 or the
61 .Xr proc 1
62 tools on GNU/Linux applications. However, not every native tool will work
63 properly within an
64 .Em lx
65 zone.
66 .Sh CONFIGURATION
67 The
68 .Em kernel-version
69 attribute can be included in the zone's
70 .Xr zonecfg 1m
71 settings as a way to specify the Linux version that the zone is emulating. For
72 example, the value could be
73 .Em 3.13.0 .
74 .Sh LIMITATIONS
75 The brand only supports the exclusive IP stack zone configuration.
76 .Pp
77 Most modern GNU/Linux application software runs on
78 .Em lx ,
79 but because there are some system calls or file systems which are not currently
80 implemented, it's possible that an application won't run. This does not
81 preclude the application running in the future as the
82 .Em lx
83 brand adds new capabilities.
84 .Pp
85 Because there is only the single SunOS kernel running on the system, there
86 is no support for any Linux kernel-level modules. That is, there is no support
87 for add-on drivers or any other modules that are part of the Linux kernel
88 itself. If that is required, a full virtual machine should be used instead of
89 an
90 .Em lx
91 branded zone.
92 .Pp
93 Any core files produced within the zone are in the native SunOS format.
94 .Pp
95 As with any zone, the normal security mechanisms and privileges apply. Thus,
96 certain operations (for example, changing the system time), will not be allowed
97 unless the zone has been configured with the appropriate additional privileges.
98 .Sh SEE ALSO
99 .Xr mdb 1 ,
100 .Xr proc 1 ,
101 .Xr dtrace 1m ,
102 .Xr zfs 1m ,
103 .Xr zoneadm 1m ,
104 .Xr zonecfg 1m ,
105 .Xr brands 5 ,
106 .Xr privileges 5 ,
107 .Xr resource_controls 5 ,
108 .Xr zones 5