## INSTALLATION

Installation Rocky Linux 9 Minimal

Partitionierung (LVM; XFS als Filesystem):
```
/boot      1 GB
/          64 GB
/home      32 GB
swap       4 GB
```

Netzwerkkonfiguration:
```
# hostnamectl hostname ryovpn01.rych01.rychiger.com

Hostname: ryovpn01.rych01.rychiger.com
DNS:      8.8.8.8

```
 
Installation diverse Pakete
```
# yum update 
# yum install kbd-legacy
# dracut -f
```

Anschliessend Installation OpenVPN:
```
# yum install epel-release
# yum install openvpn -y

Noch ein paar Zusatzpakete:
# yum install s-nail -y
# yum install git -y
# yum install net-tools -y
# yum install policycoreutils-devel -y
# yum install bridge-utils -y
# yum install tcpdump -y
# yum install python3-bcrypt -y
# yum install tar -y
```

Wegen Entropy:
```
# yum install haveged
# systemctl enable haveged
# systemctl start haveget
Test:
# cat /proc/sys/kernel/random/entropy_avail
```


Installation NGINX (Zugang fuer Statusabfragen):
```
# yum install nginx
# systemctl enable nginx

Konfiguration /etc/nginx/nginx.conf:
...
       root         /opt/openvpn/status;
...

Installation von altem Server oder git uebernehmen...
# cd /opt
# git clone https://gitlab.com/drpuur/rych-openvpn.git openvpn    # use personal access token in Gitlab
# cd openvpn && git checkout rockylinux9-based

SELinux:
# semanage fcontext -a -t httpd_sys_content_t /opt/openvpn/status/openvpnserver-status.log
# semanage fcontext -a -t httpd_sys_content_t /opt/openvpn/status/openvpnserver-status-443.log
# semanage port -a -t ssh_port_t -p tcp 2022
# restorecon -v /opt/openvpn/status/openvpnserver-status.log
# restorecon -v /opt/openvpn/status/openvpnserver-status-443.log

Link erstellen:
# cd /etc/openvpn && ln -s /opt/openvpn/config/server.conf .
```


Prinzipieller Aufbau:

```
ens4: Netzwerkinterface Richtung Intranet
ens3: Netzwerkinterface Richtung Internet

ens3 (192.168.99.111/24) ==> hier hoert OpenVPN und bildet das Device tap0

Eine zweite OpenVPN Instanz bildet das Device tap1 (443/TCP)

-- ens3 => tap0 --+-- br0 (10.3.5.10/16)
           tap1   |
-- ens4 ----------+
```

OpenVPN Client Range: 10.3.6.1 bis 10.3.7.254 (mit PUSH gemanaged)

```
Disable IPv6:

# nmcli connection modify ens3 ipv6.method "disabled"
# nmcli connection modify ens4 ipv6.method "disabled"

Set end4 to unmanaged:

[root@ryovpn01 ~]# cat /etc/NetworkManager/conf.d/99-unmanaged-devices.conf
[keyfile]
unmanaged-devices=interface-name:ens4
```

```
/etc/ssh/sshd_config:
Port 22
Port 2022
...
```


```
/etc/cron.d/reboot-if-ping-fails:
MAILTO=root
02 * * * * root /opt/openvpn/scripts/reboot-if-ping-fails.sh
```

```
/etc/hosts:
127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
#::1         localhost localhost.localdomain localhost6 localhost6.localdomain6
```

Startup mit Systemd einrichten:
gemaess /opt/openvpn/systemd/README

Verzeichnis /opt/openvpn/users ccd, log und status  muss angelegt werden:
```
# mkdir /opt/openvpn/users
# mkdir /opt/openvpn/ccd
# mkdir /opt/openvpn/status
# mkdir /opt/openvpn/log
```

User anlegen:
```
# groupadd sysadmin
# useradd -m -g sysadmin sysadmin
# passwd sysadmin

# groupadd sysoper
# useradd -m -g sysoper -s /opt/openvpn/sysoper/sysoper_shell sysoper
# passwd sysoper

# cat /etc/sudoers.d/sysoper
sysoper ALL=NOPASSWD: /usr/bin/systemctl start myopenvpn
sysoper ALL=NOPASSWD: /usr/bin/systemctl stop myopenvpn
sysoper ALL=NOPASSWD: /usr/bin/systemctl status myopenvpn
```
Git Config:
```
# cat .gitconfig
[user]
	name = Joerg Lehmann
	email = joerg.lehmann@nbit.ch
[http]
	sslVerify = false
```


Testen der Verbindung

```
[joerg@cinnamon test-openvpn-rychiger]$ sudo openvpn --config ewon.rychiger.com.conf

[joerg@cinnamon test-openvpn-rychiger]$ more ewon.rychiger.com.conf
dev tap1
proto tcp
suppress-timestamps
status-version 2
rport 443
verb 1
mute 10
comp-lzo
persist-key
up-delay
route-delay 0
nobind
client
tls-exit
ca cacert.pem
reneg-sec 86400
keepalive 30 120
hand-window 140
remote ewon.rychiger.com
resolv-retry 60
auth-user-pass


am besten auf Linux:

Testuser erstellt mit 

$ string_to_hash="7355+TT" /opt/openvpn/sysoper/hashme.py  >/opt/openvpn/users/testuser.pwd

auch CCD-File erstellen, siehe unten

[root@ryovpn openvpn]# more users/testuser.pwd ccd/testuser
::::::::::::::
users/testuser.pwd
::::::::::::::
$2b$12$OkJpfcPt7Uk8DMVjBbuStedJ63rahYw05E7vNAg9PQigL97ox18Am
::::::::::::::
ccd/testuser
::::::::::::::
ifconfig-push 10.3.6.254 255.255.0.0