cloud engineer
When you stand up an AWS instance, it’s only accessible via SSH key using the default user, typically ec2-user.
Add password to ec2-user, then enable password authentication to ‘yes’ in SSH.
# Add password to ec2-user sudo passwd ec2-user # edit ssh config vim /etc/ssh/sshd_config # enable password authentication PasswordAuthentication yes # save file and exit |
# Add password to ec2-user sudo passwd ec2-user # edit ssh config vim /etc/ssh/sshd_config # enable password authentication PasswordAuthentication yes # save file and exit
Restart SSH service.
systemctl restart sshd.service |
systemctl restart sshd.service
This is a Bash script to restart a service.
#!/bin/bash SERVICE=google_osconfig_agent AGENT=google-osconfig-agent if (( $(ps -ef | grep -v grep | grep $SERVICE | wc -l) > 0 )) then echo "$AGENT service running, everything is fine" else echo "$AGENT is not running" echo "Restarting service" systemctl start $AGENT sleep 5s if (( $(ps -ef | grep -v grep | grep $SERVICE | wc -l) > 0 )) then sleep 2s echo "$AGENT service is now running" fi fi |
#!/bin/bash SERVICE=google_osconfig_agent AGENT=google-osconfig-agent if (( $(ps -ef | grep -v grep | grep $SERVICE | wc -l) > 0 )) then echo "$AGENT service running, everything is fine" else echo "$AGENT is not running" echo "Restarting service" systemctl start $AGENT sleep 5s if (( $(ps -ef | grep -v grep | grep $SERVICE | wc -l) > 0 )) then sleep 2s echo "$AGENT service is now running" fi fi
If you don’t have it installed.
yum install screen apt install screen |
yum install screen apt install screen
Before you run a process, run screen, and detach.
screen # run the command ping yahoo.com # ctrl-a and ctrl-d to detach |
screen # run the command ping yahoo.com # ctrl-a and ctrl-d to detach
To reattach, get a list of screen sessions, and attach to it.
screen -ls # result is somewhat similar to below 4452.hostname # attach to it screen -dr 4452.hostname |
screen -ls # result is somewhat similar to below 4452.hostname # attach to it screen -dr 4452.hostname
To stop, just type exit from the screen terminal.