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What can you do with a QEMU monitor?
The QEMU monitor is used to give complex commands to the QEMU emulator. You can use it to: Remove or insert removable media images (such as CD-ROM or floppies). Freeze/unfreeze the Virtual Machine (VM) and save or restore its state from a disk file.
Which is live migration feature does QEMU support?
QEMU also supports the migration of both transient bitmaps (tracking any arbitrary image format) or persistent bitmaps (qcow2) via live migration. QEMU supports all documented features below on the qcow2 image format. However, qcow2 is only strictly necessary for the persistence feature, which writes bitmap data to disk upon close.
What kind of bitmaps does QEMU support?
QEMU also supports the migration of both transient bitmaps (tracking any arbitrary image format) or persistent bitmaps (qcow2) via live migration. QEMU supports all documented features below on the qcow2 image format.
How does QEMU do a snapshot of an image?
It is a work in progress and things may change as we progress. The idea is to be able to issue a command to QEMU via the monitor or QMP, which causes QEMU to create a new snapshot image with the original image as the backing file, mounted read-only. This will allow the original image file to be backed up.
How are disk images written to in QEMU?
If you use the option -snapshot, all disk images are considered as read only. When sectors in written, they are written in a temporary file created in /tmp. You can however force the write back to the raw disk images by using the commit monitor command (or C-a s in the serial console).
How to print physical address in QEMU monitor?
Print the guest physical address at which the guest’s virtual address addr is mapped based on the mapping for the current CPU. Print expression value. Only the format part of fmt is used. Read I/O port. Write to I/O port. Send keys to the guest. keys could be the name of the key or the raw value in hexadecimal format.
What happens when a QEMU drive is deleted?
Once a drive has been deleted, the QEMU Block layer returns -EIO which results in IO errors in the guest for applications that are reading/writing to the device. These errors are always reported to the guest, regardless of the drive’s error actions (drive options rerror, werror).
How to get device index numbers from QEMU monitor?
Move the active mouse pointer to the specified coordinates dx, dy with the optional scroll axis dz. Change the state of the mouse buttons (1=left, 2=middle, 4=right). Set which mouse device receives events. Device index numbers can be obtained with the info mice command.
How to capture network traffic from within QEMU?
You can capture network traffic from within QEMU using the filter-dump object, like this: -netdev user,id=u1 -device e1000,netdev=u1 -object filter-dump,id=f1,netdev=u1,file=dump.dat Once you’ve shut down QEMU, you can examine the dump.dat file with tools like Wireshark.
What kind of network backend does QEMU use?
By default QEMU will create a SLiRP user network backend and an appropriate virtual network device for the guest (eg an E1000 PCI card for most x86 PC guests), as if you had typed -net nic -net user on your command line.