Browse Source

added content to the linux cheatsheet

main
Ken Schaefer 2 years ago
parent
commit
50a88eacd0
  1. 139
      Runbooks/linux.md

139
Runbooks/linux.md

@ -1,14 +1,14 @@
# Linux Stuff
## Hardening
## Install distro
1. Automatic Updates (Non-prod only)
2. SSH Logins
3. Lockdown logins
4. Firewall
### Automatic Updates
## Post install
```
apt update
apt upgrade
```
## Automatic Updates
To do updates manually. Don't do this on Production servers because you should have better planning to upgrade you key servers.
```
@ -28,10 +28,37 @@ Configure the utility
dpkg-reconfigure --priority=low unattended-upgrades
```
### SSH Logins
## Create new sudo account
```
sudo adduser {username}
sudo usermod -aG sudo {username}
```
### Lockdown Logins
## Disable root
```
sudo passwd -l root
```
## SSH Logins
### Install openssh
```
sudo apt install openssh-server
```
### Setup key generated login
```
ssh-keygen
```
Go to client machine
```
ssh-keygen
ssh-copy-d username@ipaddress
```
### Lockdown Logins
Edit the following file in nano on the server:
```
@ -40,14 +67,98 @@ sudo nano /etc/ssh/sshd_config
Make the following changes:
1. Change the **Port** to something other than 22
2. Uncomment **AddressFamily**
3. Change AddressFamily to **inet**
4. Change PermitRooLogin to **no**
5. Change PasswordAuthentication to **no**
1. Change PasswordAuthentication to **no**
2. Change ChallengeResponseAuthentication to **no**
Save the file and restart the ssh service
```
sudo systemctl restart sshd
```
## Static IP
```
sudo nano /etc/netplan/01-netcfg.yaml
network:
version: 2
renderer: networkd
ethernets:
ens18:
dhcp4: no
addresses:
- 192.168.5.50/24
gateway: 192.168.5.99
nameservers:
addresses: [192.168.5.25]
sudo netplan apply
```
## Fix LVM
```
sudo lvm
lvm > lvextend -l +100%FREE /dev/ubuntu-vg/ubuntu-lv
exit
sudo resize2fs /dev/ubuntu-vg/ubuntu-lv
```
## Change HOSTNAME
```
sudo hostnamectl set-hostname {hostname}
hostnamectl
sudo nano /etc/hosts
/* change hostname in hosts file */
```
## Change timezone
```
timedatectl
timedatectl list-timezones
sudo timedatectl set-timezone America/Chicago
```
## Install Guest Agent for Proxmox
Applies only if this box is in a Proxmox server
1. Open Proxmox
2. Click Options
3. Turn on QEMU Agent
```
sudo apt install qemu-guest-agent
sudo shutdown
```
## Configure Firewall
```
sudo ufw status
sudo ufw default allow outgoing
sudo ufw default deny incoming
sudo ufw allow ssh
sudo ufw enable
```
## Install fail2ban
```
sudo apt install fail2ban
sudo cp /etc/fail2ban/fail2ban.{conf,local}
sudo cp /etc/fail2ban/jail.{conf,local}
sudo nano fail2ban.local
loglevel = INFO
logtarget = /var/log/fail2ban.log
sudo nano /etc/fail2ban/jail.local
bantime = 10m
findtime = 10m
maxretry = 5
backend = systemd
sudo systemctl restart fail2ban
sudo fail2ban-client status /* use to review banned */
```
Loading…
Cancel
Save