--- name: "virt-log" section: "1" platform: "linux" package: "guestfs-tools" version: "1.56.1-1" release: "Arch Linux 2026-11-01" platforms: ["linux"] url: "https://new.carta.tech/virt-log" --- # virt-log(1) Display log files from a virtual machine ## NAME virt-log - Display log files from a virtual machine ## SYNOPSIS ``` virt-log [--options] -d domname virt-log [--options] -a disk.img [-a disk.img ...] ``` ## DESCRIPTION `"virt-log"` is a command line tool to display the log files from the named virtual machine (or disk image). This tool understands and displays both plain text log files (eg. */var/log/messages*) and binary formats such as the systemd journal. To display other types of files, use [**virt-cat**(1)](/virt-cat/1.md). To follow (tail) text log files, use [**virt-tail**(1)](/virt-tail/1.md). To copy files out of a virtual machine, use [**virt-copy-out**(1)](/virt-copy-out/1.md). To display the contents of the Windows Registry, use [**virt-win-reg**(1)](/virt-win-reg/1.md). ## EXAMPLES Display the complete logs from a guest: ``` virt-log -d mydomain | less ``` Find out what DHCP IP address a VM acquired: ``` virt-log -d mydomain | grep 'dhclient.*bound to' ``` ## OPTIONS - **--help** Display brief help. - **-a** file - **--add** file Add *file* which should be a disk image from a virtual machine. If the virtual machine has multiple block devices, you must supply all of them with separate *-a* options. The format of the disk image is auto-detected. To override this and force a particular format use the *--format=..* option. - **-a URI** - **--add URI** Add a remote disk. See "ADDING REMOTE STORAGE" in [**guestfish**(1)](/guestfish/1.md). - **--blocksize=512** - **--blocksize=4096** - **--blocksize** This parameter sets the sector size of the disk image. It affects all explicitly added subsequent disks after this parameter. Using *--blocksize* with no argument switches the disk sector size to the default value which is usually 512 bytes. See also "guestfs\_add\_drive\_opts" in [**guestfs**(3)](/guestfs/3.md). - **-c** URI - **--connect** URI If using libvirt, connect to the given *URI*. If omitted, then we connect to the default libvirt hypervisor. If you specify guest block devices directly (*-a*), then libvirt is not used at all. - **-d** guest - **--domain** guest Add all the disks from the named libvirt guest. Domain UUIDs can be used instead of names. - **--echo-keys** When prompting for keys and passphrases, virt-log normally turns echoing off so you cannot see what you are typing. If you are not worried about Tempest attacks and there is no one else in the room you can specify this flag to see what you are typing. - **--format=raw\|qcow2\|..** - **--format** The default for the *-a* option is to auto-detect the format of the disk image. Using this forces the disk format for *-a* options which follow on the command line. Using *--format* with no argument switches back to auto-detection for subsequent *-a* options. For example: ``` virt-log --format=raw -a disk.img ``` forces raw format (no auto-detection) for *disk.img*. ``` virt-log --format=raw -a disk.img --format -a another.img ``` forces raw format (no auto-detection) for *disk.img* and reverts to auto-detection for *another.img*. If you have untrusted raw-format guest disk images, you should use this option to specify the disk format. This avoids a possible security problem with malicious guests (CVE-2010-3851). - **--key** SELECTOR Specify a key for LUKS, to automatically open a LUKS device when using the inspection. - **--key** NAME**:key:**KEY\_STRING - **--key** UUID**:key:**KEY\_STRING - **--key** **all:key:**KEY\_STRING `"NAME"` is the libguestfs device name (eg. `"/dev/sda1"`). `"UUID"` is the device UUID. `"all"` means try the key against any encrypted device. Use the specified `"KEY_STRING"` as passphrase. - **--key** NAME**:file:**FILENAME - **--key** UUID**:file:**FILENAME - **--key** **all:file:**FILENAME Read the passphrase from *FILENAME*. - **--key** NAME**:clevis** - **--key** UUID**:clevis** - **--key** **all:clevis** Attempt passphrase-less unlocking for the device with Clevis, over the network. Please refer to "ENCRYPTED DISKS" in [**guestfs**(3)](/guestfs/3.md) for more information on network-bound disk encryption (NBDE). Note that if any such option is present on the command line, QEMU user networking will be automatically enabled for the libguestfs appliance. - **--keys-from-stdin** Read key or passphrase parameters from stdin. The default is to try to read passphrases from the user by opening */dev/tty*. If there are multiple encrypted devices then you may need to supply multiple keys on stdin, one per line. - **-v** - **--verbose** Enable verbose messages for debugging. - **-V** - **--version** Display version number and exit. - **-x** Enable tracing of libguestfs API calls. ## EXIT STATUS This program returns 0 if successful, or non-zero if there was an error. ## SEE ALSO [**guestfs**(3)](/guestfs/3.md), [**guestfish**(1)](/guestfish/1.md), [**virt-cat**(1)](/virt-cat/1.md), [**virt-copy-out**(1)](/virt-copy-out/1.md), [**virt-tail**(1)](/virt-tail/1.md), [**virt-tar-out**(1)](/virt-tar-out/1.md), [**virt-win-reg**(1)](/virt-win-reg/1.md), http://libguestfs.org/. ## AUTHOR Richard W.M. Jones http://people.redhat.com/~rjones/ ## COPYRIGHT Copyright (C) 2010-2025 Red Hat Inc. ## LICENSE This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. ## BUGS To get a list of bugs against libguestfs, use this link: https://bugzilla.redhat.com/buglist.cgi?component=libguestfs&product=Virtualization+Tools To report a new bug against libguestfs, use this link: https://bugzilla.redhat.com/enter\_bug.cgi?component=libguestfs&product=Virtualization+Tools When reporting a bug, please supply: - • The version of libguestfs. - • Where you got libguestfs (eg. which Linux distro, compiled from source, etc) - • Describe the bug accurately and give a way to reproduce it. - • Run [**libguestfs-test-tool**(1)](/libguestfs-test-tool/1.md) and paste the **complete, unedited** output into the bug report.