Difference between revisions of "OpenVPN: IPv4 /32 multi-client"

Revision as of 06:15, 17 February 2019

sumber: https://www.ostechnix.com/easiest-way-install-configure-openvpn-server-linux/

Topology

CLIENT 1 ------- HOST A ---------------- HOST B --------- CLIENT 2
                 ovpn server             ovpn client

Host A akan berfungsi sebagai OpenVPN Server.

OS : Ubuntu 18.04
IP : 192.168.0.239/24
hostname : vpnserver

Host B akan berfungsi sebagai OpenVPN client

OS : Ubuntu 18.04
IP : 192.168.0.237/24

Buat Client Config di Server

Konfigurasi client dibuat di server menggunakan

cd /usr/local/src/
bash openvpn-install.sh

Keluar

Looks like OpenVPN is already installed.

What do you want to do?
   1) Add a new user
   2) Revoke an existing user
   3) Remove OpenVPN
   4) Exit
Select an option [1-4]:

Pilih 1 dan akan dibuatkan config untuk client2 dst. File ini ada di /root/client2.ovpn. Copykan file tersebut ke client.

Konfigurasi OpenVPN Client

Pastikan openvpn terinstalsi

sudo su
apt install openssh-server openvpn

Edit /etc/hosts isi dengan nama OpenVPN server

192.168.0.239 vpnserver

Jalankan OpenVPN client

cd ~
sudo su
openvpn --config client2.ovpn

Akan keluar kira-kira

Sat Feb 16 08:24:44 2019 Unrecognized option or missing or extra parameter(s) in client.ovpn:14: block-outside-dns (2.4.4)
Sat Feb 16 08:24:44 2019 OpenVPN 2.4.4 x86_64-pc-linux-gnu [SSL (OpenSSL)] [LZO] [LZ4] [EPOLL] [PKCS11] [MH/PKTINFO] [AEAD] built on Feb 10 2018
Sat Feb 16 08:24:44 2019 library versions: OpenSSL 1.1.0g  2 Nov 2017, LZO 2.08
Sat Feb 16 08:24:44 2019 Outgoing Control Channel Authentication: Using 512 bit message hash 'SHA512' for HMAC authentication
Sat Feb 16 08:24:44 2019 Incoming Control Channel Authentication: Using 512 bit message hash 'SHA512' for HMAC authentication
Sat Feb 16 08:24:44 2019 TCP/UDP: Preserving recently used remote address: [AF_INET]192.168.0.239:1194
Sat Feb 16 08:24:44 2019 Socket Buffers: R=[212992->212992] S=[212992->212992]
Sat Feb 16 08:24:44 2019 UDP link local: (not bound)
Sat Feb 16 08:24:44 2019 UDP link remote: [AF_INET]192.168.0.239:1194
Sat Feb 16 08:24:44 2019 TLS: Initial packet from [AF_INET]192.168.0.239:1194, sid=5ece0ce6 888b9e5b
Sat Feb 16 08:24:44 2019 VERIFY OK: depth=1, CN=ChangeMe
Sat Feb 16 08:24:44 2019 VERIFY KU OK
Sat Feb 16 08:24:44 2019 Validating certificate extended key usage
Sat Feb 16 08:24:44 2019 ++ Certificate has EKU (str) TLS Web Server Authentication, expects TLS Web Server Authentication
Sat Feb 16 08:24:44 2019 VERIFY EKU OK
Sat Feb 16 08:24:44 2019 VERIFY OK: depth=0, CN=server
Sat Feb 16 08:24:44 2019 Control Channel: TLSv1.2, cipher TLSv1.2 ECDHE-RSA-AES256-GCM-SHA384, 2048 bit RSA
Sat Feb 16 08:24:44 2019 [server] Peer Connection Initiated with [AF_INET]192.168.0.239:1194
Sat Feb 16 08:24:45 2019 SENT CONTROL [server]: 'PUSH_REQUEST' (status=1)
Sat Feb 16 08:24:45 2019 PUSH: Received control message: 'PUSH_REPLY,redirect-gateway def1 bypass-dhcp,dhcp-option DNS 192.168.0.222,route-gateway  10.8.0.1,topology subnet,ping 10,ping-restart 120,ifconfig 10.8.0.2 255.255.255.0,peer-id 0,cipher AES-256-GCM '
Sat Feb 16 08:24:45 2019 OPTIONS IMPORT: timers and/or timeouts modified
Sat Feb 16 08:24:45 2019 OPTIONS IMPORT: --ifconfig/up options modified
Sat Feb 16 08:24:45 2019 OPTIONS IMPORT: route options modified
Sat Feb 16 08:24:45 2019 OPTIONS IMPORT: route-related options modified
Sat Feb 16 08:24:45 2019 OPTIONS IMPORT: --ip-win32 and/or --dhcp-option options modified
Sat Feb 16 08:24:45 2019 OPTIONS IMPORT: peer-id set
Sat Feb 16 08:24:45 2019 OPTIONS IMPORT: adjusting link_mtu to 1624
Sat Feb 16 08:24:45 2019 OPTIONS IMPORT: data channel crypto options modified
Sat Feb 16 08:24:45 2019 Data Channel: using negotiated cipher 'AES-256-GCM'
Sat Feb 16 08:24:45 2019 Outgoing Data Channel: Cipher 'AES-256-GCM' initialized with 256 bit key
Sat Feb 16 08:24:45 2019 Incoming Data Channel: Cipher 'AES-256-GCM' initialized with 256 bit key
Sat Feb 16 08:24:45 2019 ROUTE_GATEWAY 192.168.0.222/255.255.255.0 IFACE=enp0s3 HWADDR=08:00:27:16:69:ed
Sat Feb 16 08:24:45 2019 TUN/TAP device tun0 opened
Sat Feb 16 08:24:45 2019 TUN/TAP TX queue length set to 100
Sat Feb 16 08:24:45 2019 do_ifconfig, tt->did_ifconfig_ipv6_setup=0
Sat Feb 16 08:24:45 2019 /sbin/ip link set dev tun0 up mtu 1500
Sat Feb 16 08:24:45 2019 /sbin/ip addr add dev tun0 10.8.0.2/24 broadcast 10.8.0.255
Sat Feb 16 08:24:45 2019 /sbin/ip route add 192.168.0.239/32 dev enp0s3
Sat Feb 16 08:24:45 2019 /sbin/ip route add 0.0.0.0/1 via 10.8.0.1
Sat Feb 16 08:24:45 2019 /sbin/ip route add 128.0.0.0/1 via 10.8.0.1
Sat Feb 16 08:24:45 2019 WARNING: this configuration may cache passwords in memory -- use the auth-nocache option to prevent this
Sat Feb 16 08:24:45 2019 Initialization Sequence Completed

Cek interface, akan muncul tun0

ifconfig

tun0: flags=4305<UP,POINTOPOINT,RUNNING,NOARP,MULTICAST>  mtu 1500
        inet 10.8.0.3  netmask 255.255.255.0  destination 10.8.0.2
        inet6 fe80::28c4:3e38:2497:e12a  prefixlen 64  scopeid 0x20<link>
        unspec 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00  txqueuelen 100  (UNSPEC)
        RX packets 51  bytes 11522 (11.5 KB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 134  bytes 43524 (43.5 KB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

Cek sambungan

ping -c3 10.8.0.1

Sample output:

PING 10.8.0.1 (10.8.0.1) 56(84) bytes of data.
64 bytes from 10.8.0.1: icmp_seq=1 ttl=64 time=0.539 ms
64 bytes from 10.8.0.1: icmp_seq=2 ttl=64 time=1.17 ms
64 bytes from 10.8.0.1: icmp_seq=3 ttl=64 time=0.921 ms

--- 10.8.0.1 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2007ms
rtt min/avg/max/mdev = 0.539/0.878/1.176/0.264 ms

Cek routing

route -n

Sample output

Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
0.0.0.0         10.8.0.1        128.0.0.0       UG    0      0        0 tun0

Anda sudah tersambung ke VPN dengan IP 10.8.0.0/24

Referensi

Pranala Menarik

OpenVPN
IPv6

@@ Line 23: / Line 23: @@
   IP : 192.168.0.237/24
-==Buat Clint Config di Server==
+==Buat Client Config di Server==
 Konfigurasi client dibuat di server menggunakan
@@ Line 44: / Line 44: @@
 Pilih 1 dan akan dibuatkan config untuk client2 dst. File ini ada di /root/client2.ovpn.
 Copykan file tersebut ke client.
 ==Konfigurasi OpenVPN Client==