linux under the hood nov23

[root@localhost ~]# history
    1  history -w
    2  history
    3  lsmod
    4  modinfo xfs
    5  modinfo cdrom
    6  history
    7  lsblk
    8  modprobe -r cdrom
    9  modprobe --remove-dependencies cdrom
   10  lsmod | grep cdrom
   11  modprobe cdrom debug=true
   12  modprobe -c | grep cdrom
   13  vim /etc/modprobe.d/cdrom.conf
   14  ls /sys/module/*/parameters
   15  ls /proc
   16  mount | grep proc
   17  less /proc/meminfo
   18  ls sys
   19  ls /proc/sys
   20  ls -l /proc
   21  cd /proc
   22  less cpuinfo
   23  lscpu
   24  less meminfo
   25  cat cmdline
   26  less modules
   27  lsmod
   28  less filesystems
   29  less devices
   30  ls -l /dev/sda2
   31  ls -l /dev/nvme0n1p2
   32  less devices
   33  ls
   34  cd 3009
   35  ls
   36  cat cmdline
   37  cd ..
   38  ps
   39  ls
   40  cat 2820/cmdline
   41  cd 999
   42  ls
   43  cat cmdline
   44  cat syscall
   45  ls
   46  less status
   47  cd
   48  git clone https://github.com/sandervanvugt/luth
   49  history
   50  cat /proc/sys/vm/swappiness
   51  echo 50 > /proc/sys/vm/swappiness
   52  cat /proc/sys/vm/swappiness
   53  vim /etc/sysctl.conf
   54  cd /etc/sysctl.d/
   55  ls
   56  ls -l
   57  vim 98-swappiness.conf
   58  cd
   59  echo h > /proc/sysrq-trigger
   60  dmesg
   61  dnf install watchdog
   62  systemctl enable --now watchdog
   63  systemctl status watchdog
   64  modprobe -i softdog
   65  rm /etc/modprobe.d/cdrom.conf -f
   66  lsmod | grep soft
   67  #echo c> /proc/sysrq-trigger
   68  history -w
   69  history
   70  vim /etc/watchdog.conf
   71  dnf install bpftrace
   72  cd luth/
   73  ls
   74  cat disk_io.bt
   75  bpftrace luth/disk_io.bt
   76  bpftrace disk_io.bt
   77  uname -r
   78  podman run -it docker.io/library/ubuntu:latest
   79  history -w
   80  history
   81  vim /etc/watchdog.conf
   82  dnf install bpftrace
   83  cd luth/
   84  ls
   85  cat disk_io.bt
   86  bpftrace luth/disk_io.bt
   87  bpftrace disk_io.bt
   88  uname -r
   89  podman run -it docker.io/library/ubuntu:latest
   90  history -w
   91  sync
   92  reboot
   93  history
   94  man 2 execve
   95  ps aux | less
   96  ps aux | grep fire
   97  cd /proc/4402
   98  cd fd
   99  ls -l | less
  100  cd
  101  top
  102  ps -T -p 2736
  103  dnf install epel-release
  104  dnf install -y htop
  105  cd luth/
  106  ls
  107  gcc -o zombie zombie.c
  108  ls
  109  ./zombie &
  110  rm zombie
  111  vim zombie.c
  112  gcc -o zombie zombie.c
  113  ./zombie &
  114  ps aux | grep defunc
  115  kill -9 4805
  116  ps aux | grep defunc
  117  ps -A -ostat,pid,ppid | grep -Z
  118  ps -A -ostat,pid,ppid
  119  ps -A -ostat,pid,ppid | grep -Z
  120  ps -A -ostat,pid,ppid | grep -Z --
  121  kill -s SIGCHLD 4804
  122  ps aux | grep defunc
  123  ps aux | grep 4804
  124  kill -s SIGCHLD 3534
  125  ps aux | grep defunc
  126  kill -p 4805
  127  kill -9 4805
  128  ps aux | grep defunc
  129  ps aux | grep 3534
  130  history -w
  131  chrt --helpo
  132  chrt --help
  133  chrt -r dd if=/dev/zero of=/dev/null
  134  chrt -r "dd if=/dev/zero of=/dev/null"
  135  chrt -r 20 "dd if=/dev/zero of=/dev/null"
  136  history
  137  chrt -r 20 dd if=/dev/zero of=/dev/null
  138  history
  139  ls -l /etc/shadow
  140  chmod u-rw /etc/shadow
  141  ls -l /etc/shadow
  142  whoami
  143  cat /etc/shadow
  144  ls -l /etc/shadow
  145  man 7 capabilities
  146  ldd $(which ls)
  147  man libc
  148  strace ls
  149  strace ls | less
  150  strace ls 2> lsout.txt
  151  less lsout.txt
  152  strace -c ls
  153  strace -c echo *
  154  less lsout.txt
  155  exit
  156  top
  157  less /proc/999/maps
  158  pmap --help
  159  pmap 999
  160  echo $$
  161  dnf install -y zsh
  162  zsh
  163  echo $$
  164  exec zsh
  165  echo $$
  166  exec /bin/zsh
  167  history