Azure VM (Debian 11.9) root directory 100% full...but its not!

Please help, I am at the end of my tether with this stupid VM! Its an Azure VM running Debian 11.9 with a primary disk of 128GB and a secondary disk of 100GB. It is reporting that / is currently 100% full. root@SYS-801:/# df -h Filesystem Size Used Avail Use% Mounted on udev 3.9G 0 3.9G 0% /dev tmpfs 791M 86M 706M 11% /run /dev/sdb1 126G 126G 0 100% / tmpfs 3.9G 0 3.9G 0% /dev/shm tmpfs 5.0M 0 5.0M 0% /run/lock /dev/sdc1 16G 8.0K 15G 1% /swap/mntold/resource /dev/sdb15 124M 11M 114M 9% /boot/efi //logs.windows.net/sys 5.0T 23G 5.0T 1% /syslogs tmpfs 791M 0 791M 0% /run/user/1000 But its not, I think something is hidden somewhere but for the life of me I cannot find it. I've spent 3 days solid trying different things and this is the current stat I am in. The primary disk was originally 30GB and showing full so I increased it in Azure ans still its just eating up whatever I assign to it. root@SYS-801:/# du -a -h --max-depth=1 | sort -hr du: cannot access './proc/490298/task/490298/fd/3': No such file or directory du: cannot access './proc/490298/task/490298/fdinfo/3': No such file or directory du: cannot access './proc/490298/fd/4': No such file or directory du: cannot access './proc/490298/fdinfo/4': No such file or directory 27G . 22G ./syslogs 3.8G ./var 1.1G ./opt 779M ./usr 236M ./home 88M ./run 77M ./boot 5.6M ./etc 68K ./tmp 68K ./root 16K ./lost+found 12K ./swap 4.0K ./srv 4.0K ./resource 4.0K ./media 4.0K ./ As you can see, nothing is showing any larger than 22G so what is using up all of the extra space? The only thing odd I can see is that the seconday 100GB isn't showing as mounted to anything. root@SYS-801:/# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sda 8:0 0 100G 0 disk └─sda1 8:1 0 100G 0 part sdb 8:16 0 128G 0 disk ├─sdb1 8:17 0 127.9G 0 part / ├─sdb14 8:30 0 3M 0 part └─sdb15 8:31 0 124M 0 part /boot/efi sdc 8:32 0 16G 0 disk └─sdc1 8:33 0 16G 0 part /swap/resource Does it matter that its appearing in the list first? Along the way I have investigated the SWAP configuration within /etc/waagent.conf and turned off the swap feature to rule tis out. # Format if unformatted. If 'n', resource disk will not be mounted. ResourceDisk.Format=n # Create and use SWAPfile on resource disk. ResourceDisk.EnableSWAP=n #Mount point for the resource disk ResourceDisk.MountPoint=/swap/resource #Size of the SWAPfile. ResourceDisk.SWAPSizeMB=0 So I don't know what else could be clinging on to this space. Rebooting doesn't change anything so I suspect it cannot be anything temporary. As part of my cleanup I may have deleted too many directories from /, and I cannot create more: root@SYS-801:/# ls bin boot dev etc home lib lib32 lib64 libx32 lost+found media opt proc root run sbin srv swap sys syslogs tmp usr var root@LIN-SYS-801-PRD:/# mkdir -p /mnt mkdir: cannot create directory ‘/mnt’: No space left on device root@SYS-801:/# cd /mnt/root bash: cd: /mnt/root: No such file or directory Any clues where I can go from here?