Inserting a CDROM iso

Daniel U. Thibault

New Member
Apr 26, 2017
How do you simulate inserting a CDROM (or DVD) into a virtual machine? I can edit the CDROM device to change it from 'no disk' to some iso I pick, but this is not detected by the running VM (an old RHEL 5.3 in this case). The VM is configured to mount removable drives when hot-plugged, mount removable media when inserted, and browse removable media when inserted.
If you talk about KVM/QEMU VM then just add a cd-drive and change it virtually over the GUI, no console action required. The CD/DVD drive is default if you create a VM so unless you removed it deliberately, it is still there and can be used:

That's precisely what I'm doing: editing the VM's CD/DVD Drive to change its ISO image from "no media" to something. But the VM is not picking up on it. I can manually mount the CD/DVD from within the VM (and access its contents, etc.), but if I then try to eject it, RHEL/CentOS complains that it wasn't mounted by HAL (Hardware Abstraction Layer).

The problem may be peculiar to older OSes like RHEL/CentOS 5, in which case I could live with having to use a "refresh" command from within it, except that I've had little luck finding such a command for RHEL/CentOS 5.
I would check the fstab and see if "mount -a" works.
as far as I can tell CD roms and floppy(!) are mounted in fstab by default.
but automount might not work for some reason so mount -a does a refresh...
Sadly, mount -a does not do the trick. The CD/DVD drive is not in fstab. RHEL/CentOS 5 must proceed some other way.
as far as I can tell RHEL/CENTOS5 uses 2 files


the auto.misc should have something like " cd -fstype=iso9660,ro,nosuid,nodev :/dev/cdrom"

and fstab "/dev/cdrom /mnt/cdrom auto defaults 0 0"

most newer system mount removable drives in "/media" rather than "/mnt" so you might want to adjust the code.
Just do a check with df and umount the disk. I've done it literally hundreds of times with RHEL/CentOS/Oracle and it is always the same. But you're right, it's not a Proxmox VE problem, but a guest OS one.
I ended up writing a shell script that checks the mount point and consequently toggles between mounting and unmounting. The mount command is enough to cause the OS to create the icon on the desktop and pop the file browser window, so it'll do.

Now if I could just get ProxMox to handle the keyboard dead keys properly...
Keyboard and Proxmox. The problem seems to have multiple facets.

For instance, from a system using fr-ca keyboard, I can open the Proxmox web interface (IP address, port 8006), log in, create and run virtual machines, etc. But if I change my Proxmox password (using Proxmox's dialog that won't display what I type) and use a dead key combination to include a character with a diacritic, it will work fine within the password-defining dialog because, of course, I use the same sequence of keystrokes in both text boxes. But if I then log out and try to log back in, that same sequence of keystrokes fails miserably. Why is Proxmox apparently using two different keyboard drivers/adaptors/translations between the two dialogs? I mean, both dialogs are supplied by Proxmox and should therefore behave identically, no?
What does not work for you?

Hint: you can always enter the keys manually via qemu monitor via send-key
The Send keys menu is useless because it offers only a very small selection of special keys (tab, ctrl-alt-delete, ctrl-alt-backspace, ctrl-alt-F1 through ctrl-alt-F12).
The other facet of the problem manifests in a Proxmox (noVNC) console: the keyboard's non-dead keys work just fine (e acute, degree, guillemets : é ° «») but any dead key stroke sequence ignores the dead key altogether. So cedilla, c (¸c) yields c instead of ç, none of the acutes, circumflexes, graves or umlauts work, etc. It's very, very annoying.

(To be fair, that's a noVNC issue, and an old one at that; see noVNC issues 21 and 411)
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Does not work. All I get if I try e.g. '# sendkey a' to a VM with a command line window open and focused is a pop-up error alert: "Permission check failed (/, Sys.Modify) (403)".

And that's not in "the other browser window" but rather in the original one, from whence I clicked Console. I've also tried clicking that menu's Console and then switch to Monitor in order to 'sendkey a', with the same error result.


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