ssh-keygen -t ed25519 -C "$USER@$(hostname)"
cp /etc/ssh/sshd_config /etc/ssh/sshd_config.save
nano /etc/ssh/sshd_config
# change the config
# Port 2233
# restart sshd deamon
systemctl restart sshd
# check if port is applied :
lsof -i -P -n | grep ssh
#!/bin/bash
mkdir -p temp
number=100000
for i in $(seq 1 $number)
do
ssh-keygen -t ed25519 -f "temp/sshkey${i}" -q -N ""
done