Linux How To Eject and Insert a CD-R/DVD-R/BD-R Disc
Many people are aware of the "eject command" which works as you would expect.
To eject the disc:
sudo eject /dev/sr0
To insert the disc again you still use the same command but with the "-t" close try toggle:
sudo eject -t /dev/sr0
........
Centos installing grub problems suspect gpt problem
grub> root (hd0,0)
root (hd0,0)
Filesystem type is ext2fs, partition type 0xfd
grub> setup (hd0)
setup (hd0)
But if you do:
root (hd1,0)
setup (hd1)
it does work, I think hd0/sda had a GPT partition that was not removed properly (what I did was just dd bs=512 count=1 the partition table from another drive since the partition table should be identical).
Checking if "/boot/grub/........