linux install cheatsheet - things i need every now and then

gistfile1.txt

#required for host command
sudo apt-get install bind9-host -y

# update IP to KeyValue-Store
# ! chmod +x !
#/opt/updateIP.sh:

#!/bin/sh

IP=$(host myip.opendns.com resolver1.opendns.com | tail -n1 | awk '{ print $4 ; exit }')
echo "ip is: ${IP}"

#IPSTR=$(echo "$IP" | sed 's/\.//g')
IPSTR=$(echo "$IP" | sed 's/\./x/g')

#replace XXXXXXX with app-key
curl -X POST http://keyvalue.immanuel.co/api/KeyVal/UpdateValue/XXXXXXXX/tip/${IPSTR} -H 'content-length: 0'

#-----------
Systemd - Service / Timer für updateIp.sh
#-----------
/etc/systemd/system/updateip.service


[Unit]
Description=Update kv store with ip

[Service]
Type=simple
ExecStart=/opt/updateIp.sh

[Install]
WantedBy=default.target

#------------
/etc/systemd/system/updateip.timer


[Unit]
Description=update ip in kv store
RefuseManualStart=no
RefuseManualStop=no

[Timer]
Persistent=false
OnBootSec=200
OnUnitActiveSec=3600
#File describing job to execute
Unit=updateip.service

[Install]
WantedBy=timers.target

#-------------
# Timer aktivieren:

systemctl daemon-reload
systemctl enable updateip.timer

#-----------------
# SSHD - enable Public-Key-Auth
/etc/ssh/sshd_config

PubkeyAuthentication yes
PasswordAuthentication no

#--------------------