ubuntu@ubuntu:~$ sudo apt update
Ign:1 cdrom://Ubuntu 20.04.4 LTS _Focal Fossa_ - Release amd64 (20220223) focal InRelease
Hit:2 cdrom://Ubuntu 20.04.4 LTS _Focal Fossa_ - Release amd64 (20220223) focal Release
Hit:4 http://archive.ubuntu.com/ubuntu focal InRelease
Get:5 http://security.ubuntu.com/ubuntu focal-security InRelease [114 kB]
Get:6 http://archive.ubuntu.com/ubuntu focal-updates InRelease [114 kB]
Get:7 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 Packages [3,015 kB]
Get:8 http://security.ubuntu.com/ubuntu focal-security/main amd64 Packages [2,610 kB]
Get:9 http://archive.ubuntu.com/ubuntu focal-updates/main Translation-en [487 kB]
Get:10 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 DEP-11 Metadata [275 kB]
Get:11 http://archive.ubuntu.com/ubuntu focal-updates/main DEP-11 48x48 Icons [60.8 kB]
Get:12 http://archive.ubuntu.com/ubuntu focal-updates/main DEP-11 64x64 Icons [98.3 kB]
Get:13 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 c-n-f Metadata [17.2 kB]
Get:14 http://archive.ubuntu.com/ubuntu focal-updates/restricted amd64 Packages [2,562 kB]
Get:15 http://archive.ubuntu.com/ubuntu focal-updates/restricted Translation-en [358 kB]
Get:16 http://archive.ubuntu.com/ubuntu focal-updates/restricted amd64 c-n-f Metadata [552 B]
Get:17 http://security.ubuntu.com/ubuntu focal-security/main Translation-en [402 kB]
Get:18 http://security.ubuntu.com/ubuntu focal-security/main amd64 DEP-11 Metadata [59.9 kB]
Get:19 http://security.ubuntu.com/ubuntu focal-security/main DEP-11 48x48 Icons [18.9 kB]
Get:20 http://security.ubuntu.com/ubuntu focal-security/main DEP-11 64x64 Icons [36.0 kB]
Get:21 http://security.ubuntu.com/ubuntu focal-security/main amd64 c-n-f Metadata [13.2 kB]
Get:22 http://security.ubuntu.com/ubuntu focal-security/restricted amd64 Packages [2,411 kB]
Get:23 http://security.ubuntu.com/ubuntu focal-security/restricted Translation-en [336 kB]
Get:24 http://security.ubuntu.com/ubuntu focal-security/restricted amd64 c-n-f Metadata [552 B]
Fetched 13.0 MB in 5s (2,703 kB/s)
Reading package lists... Done
Building dependency tree
Reading state information... Done
561 packages can be upgraded. Run 'apt list --upgradable' to see them.

ubuntu@ubuntu:~$ sudo apt install kmod
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following additional packages will be installed:
  libkmod2
The following packages will be upgraded:
  kmod libkmod2
2 upgraded, 0 newly installed, 0 to remove and 559 not upgraded.
Need to get 140 kB of archives.
After this operation, 8,192 B of additional disk space will be used.
Do you want to continue? [Y/n] Y
Get:1 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 kmod amd64 27-1ubuntu2.1 [94.8 kB]
Get:2 http://archive.ubuntu.com/ubuntu focal-updates/main amd64 libkmod2 amd64 27-1ubuntu2.1 [45.3 kB]
Fetched 140 kB in 2s (80.9 kB/s)
(Reading database ... 187727 files and directories currently installed.)
Preparing to unpack .../kmod_27-1ubuntu2.1_amd64.deb ...
Unpacking kmod (27-1ubuntu2.1) over (27-1ubuntu2) ...
Preparing to unpack .../libkmod2_27-1ubuntu2.1_amd64.deb ...
Unpacking libkmod2:amd64 (27-1ubuntu2.1) over (27-1ubuntu2) ...
Setting up libkmod2:amd64 (27-1ubuntu2.1) ...
Setting up kmod (27-1ubuntu2.1) ...
update-initramfs is disabled since running on read-only media
Processing triggers for libc-bin (2.31-0ubuntu9.2) ...
Processing triggers for systemd (245.4-4ubuntu3.15) ...
Processing triggers for man-db (2.9.1-1) ...

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

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:/#