As of last night my Ubuntu 19.04 laptop won’t boot into its latest kernel. In the hours beforehand I had completed an apt-get upgrade and autoremove. The system continued along perfectly fine. After a reboot however, I reach an (intramfs) shell prompt.  Typing exit at this prompt I am then given the alert message:  ALERT! /dev/mapper/ubuntu--vg-root does not exist. Dropping to a shell!  I have discovered that I can successfully boot into an older kernel through the grub menu.  Latest installed kernel: 5.0.0-25-generic (not working  Backup kernel: 5.0.0-21-generic (working)  My system runs an LVM partitioned drive.  I found an old thread with the same symptoms that advised running ls /dev/mapper at the intramfs shell. All that returns is /dev/mapper/control  Any help would be greatly appreciated. Also, if there’s more info required please just let me know.  TIA
today I installed Ubuntu 64-bit on a netbook. When the netbook boots this, error report appeared. I think there is a problem with the partitions.  Gave up waiting for root device. Common problems:   — Boot args (cat /proc/cmdline)     — Check rootdelay= (did the system wait long enough?)     — Check root= (did the system wait for the right device?)   — Missing modules (cat /proc/modules; ls /dev) ALERT! /dev/mapper/ubuntu--vg-root does not exist. Dropping to a shell!   BusyBox v.1.21.1 (Ubuntu 1:1.21.1-1ubuntu1) built-in shell (ash)    Enter 'help' for list of built-in commands.    (initramfs)   Output of lsblk as requested:  $ lsblk NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT sda      8:0    0 232.9G  0 disk  ├─sda1   8:1    0   231G  0 part  ├─sda2   8:2    0     1K  0 part  └─sda5   8:5    0     2G  0 part [SWAP] sr0     11:0    1   1.2G  0 rom  /cdrom loop0    7:0    0   1.1G  1 loop /rofs
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