Useful Linux commands

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lsof /folder
lsof -p 1112
lsof -u user
lsof -i TCP:22
losf -i TCP@127.0.0.1

nc -vz[4,6] <ip> <port1-port100>
nc -lk <ip> <port>
echo "hello" > /dev/tcp/<ip>/<port>

### Netplan ###
netplan set ethernets.eth0.dhcp4=true
netplan set ethernets.eth0.addresses=['10.0.0.5/24']
netplan apply
netplan status

nmap -Pn --script vuln <IP>
nmap -A <IP>
nmap -n -sP 192.168.200.0/24 (ping subnet)

grubby --update-kernel=ALL --remove-args="net.ifnames=0"
grub2-mkconfig -o /boot/grub2/grub.cfg
nmtui - edit connection and interface and reboot

ffmpeg -nostdin -i input.mov -acodec copy -vcodec libx264 -f mp4 -preset faster output.mp4
ffmpeg -i input.mp4 -c:v libx264 -crf 28 -vf "scale=1920:-1" -preset faster -movflags +faststart -c:a aac -b:a 128k output.mp4

yt-dlp --windows-filenames -x -t mp3

qemu-img resize disk.qcow2 [+]10G
qemu-img info disk.qcow2

sudo virsh net-dhcp-leases default

qemu+ssh://user@host/session?keyfile=/home/user/.ssh/id_rsa"

/etc/security/faillock.conf
faillock
faillock --user <username>
faillock --user <username> --reset
ls /var/run/faillock
rm /var/run/faillock/<username>

pam_tally2
pam_tally2 --user <username>
pam_tally2 --user <username> --reset
rm /var/log/tallylog

systemctl stop sssd
sss_cache -E
sss_cache -u jsmith
rm -rf /var/lib/sss/db/*
systemctl start sssd