ubuntu@ubuntu:~$ /usr/sbin/update-initramfs.orig.initramfs-tools
bash: /usr/sbin/update-initramfs.orig.initramfs-tools: No such file or directory

ubuntu@ubuntu:~$ sudo mount /dev/sda6 /mnt
ubuntu@ubuntu:~$ for i in /dev /dev/pts /proc /sys /run; do sudo mount -B $i /mnt/$i; done
ubuntu@ubuntu:~$ sudo chroot /mnt
root@ubuntu:/# /usr/sbin/update-initramfs.orig.initramfs-tools
bash: /usr/sbin/update-initramfs.orig.initramfs-tools: No such file or directory

root@ubuntu:/# sudo apt update
기존:1 http://mirror.kakao.com/ubuntu focal InRelease
받기:2 https://deb.nodesource.com/node_16.x focal InRelease [4,583 B]
받기:3 http://packages.microsoft.com/repos/code stable InRelease [3,589 B]
받기:4 https://dl.google.com/linux/chrome/deb stable InRelease [1,825 B]
받기:5 http://packages.microsoft.com/repos/code stable/main arm64 Packages [16.9 kB]
받기:6 http://security.ubuntu.com/ubuntu focal-security InRelease [114 kB]
받기:7 http://packages.microsoft.com/repos/code stable/main amd64 Packages [17.0 kB]
받기:8 http://packages.microsoft.com/repos/code stable/main armhf Packages [17.0 kB]
기존:9 https://linux.teamviewer.com/deb stable InRelease
받기:10 https://dl.google.com/linux/chrome/deb stable/main amd64 Packages [1,084 B]
기존:11 http://ppa.launchpad.net/graphics-drivers/ppa/ubuntu focal InRelease
받기:12 http://ppa.launchpad.net/libreoffice/ppa/ubuntu focal InRelease [23.8 kB]
기존:13 https://download.sublimetext.com apt/stable/ InRelease
받기:14 http://security.ubuntu.com/ubuntu focal-security/main i386 Packages [686 kB]
기존:15 http://ppa.launchpad.net/maarten-baert/simplescreenrecorder/ubuntu focal InRelease
받기:16 http://ppa.launchpad.net/libreoffice/ppa/ubuntu focal/main amd64 Packages [33.0 kB]
받기:17 http://ppa.launchpad.net/libreoffice/ppa/ubuntu focal/main i386 Packages [23.9 kB]
받기:18 http://ppa.launchpad.net/libreoffice/ppa/ubuntu focal/main Translation-en [13.3 kB]
받기:19 http://security.ubuntu.com/ubuntu focal-security/main amd64 Packages [2,610 kB]
받기:20 http://security.ubuntu.com/ubuntu focal-security/main Translation-en [402 kB]
받기:21 http://security.ubuntu.com/ubuntu focal-security/universe i386 Packages [634 kB]
받기:22 http://security.ubuntu.com/ubuntu focal-security/universe amd64 Packages [915 kB]
받기:23 http://security.ubuntu.com/ubuntu focal-security/universe Translation-en [192 kB]
내려받기 5,709 k바이트, 소요시간 4초 (1,336 k바이트/초)
패키지 목록을 읽는 중입니다... 완료 ( Reading the package list... Done )
의존성 트리를 만드는 중입니다       ( Building a dependency tree )
상태 정보를 읽는 중입니다... 완료   ( Reading status information... Done )
70 패키지를 업그레이드할 수 있습니다. 확인하려면 'apt list --upgradable'를 실행하십시오. ( 70 packages can be upgraded. Run 'apt list --upgradable' to check. )

root@ubuntu:/# sudo apt install kmod
패키지 목록을 읽는 중입니다... 완료
의존성 트리를 만드는 중입니다
상태 정보를 읽는 중입니다... 완료
패키지 kmod는 이미 최신 버전입니다 (27-1ubuntu2.1). ( Package kmod is already up to date (27-1ubuntu2.1). )
0개 업그레이드, 0개 새로 설치, 0개 제거 및 70개 업그레이드 안 함.

root@ubuntu:/# /usr/sbin/update-initramfs.orig.initramfs-tools
bash: /usr/sbin/update-initramfs.orig.initramfs-tools: No such file or directory

root@ubuntu:/# update-initramfs -u -k 5.15.0-88-generic
update-initramfs: Generating /boot/initrd.img-5.15.0-88-generic
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
E: /usr/share/initramfs-tools/hooks/fuse failed with return 1.
update-initramfs: failed for /boot/initrd.img-5.15.0-88-generic with 1.

root@ubuntu:/# which modprobe
/usr/sbin/modprobe

root@ubuntu:/# file /sbin/modprobe
/sbin/modprobe: cannot open `/sbin/modprobe' (No such file or directory)

root@ubuntu:/# whereis modprobe
modprobe: /usr/sbin/modprobe /usr/lib/modprobe.d /etc/modprobe.d /usr/share/man/man8/modprobe.8.gz

root@ubuntu:/# file /usr/sbin/modprobe
/usr/sbin/modprobe: symbolic link to /bin/kmod

root@ubuntu:/# update-initramfs -u -k 5.15.0-88-generic
update-initramfs: Generating /boot/initrd.img-5.15.0-88-generic
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
/usr/sbin/mkinitramfs: 75: modprobe: not found
/usr/sbin/mkinitramfs: 76: modprobe: not found
E: /usr/share/initramfs-tools/hooks/fuse failed with return 1.
update-initramfs: failed for /boot/initrd.img-5.15.0-88-generic with 1.

root@ubuntu:/usr/share#