When working with a remote VM, if I want to attach ISOs or physical discs (to install software, update drivers, etc), without the ability to do a redirect of local ISO images or the local CD/DVD drive, I first have to create an image (if a physical disc) and then copy the disc image(s) over to the remote server. Then, I have to remember to delete those from the remote server when done.
This quickly becomes untenable when working with multiple servers.
Having cdrom redirection feature will be very useful
There has been some work done in this direction in the past, see protocol and related spice & spice-gtk & qemu patches all submited at that time:
Since the patchwork link is dead, here is a link to ML archives to some of the related series: