3 virt-uname - system information for virtual machines
5 virt-dmesg - print kernel messages for virtual machines
9 virt-uname [-options] [domains...]
11 virt-dmesg [-options] [domains...]
15 These virtualization tools allow you to inspect the status of
16 virtual machines running Linux.
18 The tools all use libvirt so are capable of showing stats across a
19 variety of different virtualization systems.
25 =item B<-c uri>, B<--connect uri>
27 Connect to libvirt URI. The default is to connect to the default
28 libvirt URI, normally Xen.
32 Print the results in CSV format, suitable for importing into a
33 spreadsheet or database.
35 This option is only supported if virt-mem was built with CSV support.
39 Emit debugging information on stderr. Please supply this if you
44 Display usage summary.
46 =item B<-t memoryimage>
48 Test mode. Instead of checking libvirt for domain information, this
49 runs the virt-mem tool directly on the memory image supplied. You may
50 specify the B<-t> option multiple times.
54 Display version and exit.
56 =item B<-E auto|littleendian|bigendian>
58 =item B<-T auto|i386|x86-64|I<address>>
60 =item B<-W auto|32|64>
62 These options force the endianness, text address, and word size for
63 the subsequent domains listed on the command line (or if no domains
64 are listed, then for all domains).
66 These default to I<auto> which tries to do automatic detection (using
67 libvirt, or details from the memory images themselves). You only need
68 to use these options if virt-mem tools get the automatic detection
71 Endianness (I<-E>) sets the memory endianness, for data, pointers and
74 Text address (I<-T>) sets the base address of the kernel image. I<-T
75 i386> means to try some common addresses for i386-based kernels. I<-T
76 x86-64> means to try some common addresses for x86-64-based kernels.
77 I<-T I<address>> sets the address specifically (I<0x> prefix is
78 allowed to specify hex addresses).
80 Word size (I<-W>) sets the word size, 32 or 64 bits.
82 =item B<-A auto|i386|x86-64|...>
84 This option sets the architecture to one of a collection of known
85 architectures. It is equivalent to setting endianness and wordsize in
86 one go, but not text address.
93 f9x32kvm: Linux localhost.localdomain 2.6.24-0.155.rc7.git6.fc9 #1
94 SMP Tue Jan 15 17:52:31 EST 2008 i686 (none)
96 # virt-dmesg f9x32kvm | tail
97 <6>Bluetooth: Core ver 2.11
98 <6>NET: Registered protocol family 31
99 <6>Bluetooth: HCI device and connection manager initialized
100 <6>Bluetooth: HCI socket layer initialized
101 <6>Bluetooth: L2CAP ver 2.9
102 <6>Bluetooth: L2CAP socket layer initialized
103 <6>Bluetooth: RFCOMM socket layer initialized
104 <6>Bluetooth: RFCOMM TTY layer initialized
105 <6>Bluetooth: RFCOMM ver 1.8
106 <7>eth0: no IPv6 routers present
110 The virt-mem tools spy on the guest's memory image. There are some
111 shortcomings to this, described here.
113 (1) Only works on specific, tested releases of Linux kernels. Support
114 for arbitrary Linux kernel versions may be patchy because of changes
115 in the internal structures used. Support for non-Linux kernels is
116 currently non-existent, and probably impossible for Windows because of
117 lack of an acceptable source license.
119 (2) Heuristics are used which may mean in the worst case that the
122 (3) Structures which are frequently modified may cause errors. This
123 could be a problem if, for example, the process table in the guest is
124 being rapidly updated.
126 (4) We have to scan memory to find kernel symbols, etc., which can be
127 quite slow. Optimizing the memory scanner would help, and caching the
128 base address of the symbol table(s) would make it dramatically faster.
132 The current code tries hard to be secure against malicious guests, for
133 example guests which set up malicious kernel memory.
137 L<uname(1)>,L<dmesg(1)>,
140 L<http://www.libvirt.org/ocaml/>,
141 L<http://www.libvirt.org/>,
142 L<http://et.redhat.com/~rjones/>,
143 L<http://caml.inria.fr/>
147 Richard W.M. Jones <rjones @ redhat . com>
151 (C) Copyright 2008 Red Hat Inc., Richard W.M. Jones
154 This program is free software; you can redistribute it and/or modify
155 it under the terms of the GNU General Public License as published by
156 the Free Software Foundation; either version 2 of the License, or
157 (at your option) any later version.
159 This program is distributed in the hope that it will be useful,
160 but WITHOUT ANY WARRANTY; without even the implied warranty of
161 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
162 GNU General Public License for more details.
164 You should have received a copy of the GNU General Public License
165 along with this program; if not, write to the Free Software
166 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
168 =head1 REPORTING BUGS
170 Bugs can be viewed on the Red Hat Bugzilla page:
171 L<https://bugzilla.redhat.com/>.
173 If you find a bug in virt-mem, please follow these steps to report it:
177 =item 1. Check for existing bug reports
179 Go to L<https://bugzilla.redhat.com/> and search for similar bugs.
180 Someone may already have reported the same bug, and they may even
183 =item 2. Capture debug and error messages
187 virt-[program] --debug > virt-mem.log 2>&1
189 and keep I<virt-mem.log>. It contains error messages which you should
190 submit with your bug report.
192 =item 3. Get version of virt-mem and version of libvirt.
196 virt-[program] --version
198 =item 4. Submit a bug report.
200 Go to L<https://bugzilla.redhat.com/> and enter a new bug.
201 Please describe the problem in as much detail as possible.
203 Remember to include the version numbers (step 3) and the debug
204 messages file (step 2).
206 =item 5. Assign the bug to rjones @ redhat.com
208 Assign or reassign the bug to B<rjones @ redhat.com> (without the
209 spaces). You can also send me an email with the bug number if you
210 want a faster response.