tun0: device not found

Question

I have installed OpenVPN 2.4.7 (as client) on Debian 8 (following this) and loaded the module tun into it. Even after I start the OpenVPN I cannot see the tun0 running.

In /etc/openvpn/ I have certificate (.cer), key (.key) & .ovpn files

Here are the output of the following codes-

lsmod

Module                  Size  Used by
brcmfmac              165961  0
brcmutil                4957  1 brcmfmac
cfg80211              219211  1 brcmfmac
compat                  1055  2 cfg80211,brcmfmac
tun                    16749  1

systemctl status openvpn

● openvpn.service - OpenVPN service
   Loaded: loaded (/lib/systemd/system/openvpn.service; enabled)
   Active: active (exited) since Mon 2021-01-04 12:10:51 CET; 1h 26min ago
  Process: 15304 ExecStart=/bin/true (code=exited, status=0/SUCCESS)
 Main PID: 15304 (code=exited, status=0/SUCCESS)

ifconfig

eth0      Link encap:Ethernet  HWaddr fc:c2:3d:0c:9b:68
          inet addr:192.168.1.193  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::fec2:3dff:fe0c:9b68/64 Scope:Link
          inet6 addr: 2001:b07:6464:c46e:fec2:3dff:fe0c:9b68/64 Scope:Global
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:126868 errors:0 dropped:0 overruns:0 frame:0
          TX packets:145458 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:68031425 (64.8 MiB)  TX bytes:21688032 (20.6 MiB)
          Interrupt:48 Base address:0xc000

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:951509 errors:0 dropped:0 overruns:0 frame:0
          TX packets:951509 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1
          RX bytes:267473055 (255.0 MiB)  TX bytes:267473055 (255.0 MiB)

wlan0     Link encap:Ethernet  HWaddr 00:25:ca:07:64:dd
          UP BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:141 errors:0 dropped:17 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:32124 (31.3 KiB)  TX bytes:0 (0.0 B)

when is run openvpn --config /etc/openvpn/client.ovpn

Output/

 >     Wed Jan  6 10:28:03 2021 WARNING: file '/etc/openvpn/xxx.key' is group or others accessible
    >     Wed Jan  6 10:28:03 2021 OpenVPN 2.4.7 armv7l-unknown-linux-gnueabihf [SSL (OpenSSL)] [LZO] [LZ4] [EPOLL]
    > [MH/PKTINFO] [AEAD] built on Dec 31 2020
    >     Wed Jan  6 10:28:03 2021 library versions: OpenSSL 1.0.1t  3 May 2016, LZO 2.08
    >     Wed Jan  6 10:28:03 2021 TCP/UDP: Preserving recently used remote address: [AF_INET]xx.xxx.xxx.25:443
    >     Wed Jan  6 10:28:03 2021 Socket Buffers: R=[163840->163840] S=[163840->163840]
    >     Wed Jan  6 10:28:03 2021 UDP link local: (not bound)
    >     Wed Jan  6 10:28:03 2021 UDP link remote: [AF_INET]xx.xx.xx.xx:443
    >     Wed Jan  6 10:28:03 2021 TLS: Initial packet from [AF_INET]xx.xxx.xxx.25:443, sid=ae681168 8251285e
    >     Wed Jan  6 10:28:03 2021 VERIFY OK: depth=1, CN=Company CA
    >     Wed Jan  6 10:28:03 2021 VERIFY KU OK
    >     Wed Jan  6 10:28:03 2021 Validating certificate extended key usage
    >     Wed Jan  6 10:28:03 2021 ++ Certificate has EKU (str) TLS Web Server Authentication, expects TLS Web Server Authentication
    >     Wed Jan  6 10:28:03 2021 VERIFY EKU OK
    >     Wed Jan  6 10:28:03 2021 VERIFY OK: depth=0, CN=server
    >     Wed Jan  6 10:28:04 2021 Control Channel: TLSv1.2, cipher TLSv1/SSLv3 ECDHE-RSA-AES256-GCM-SHA384, 2048 bit RSA
    >     Wed Jan  6 10:28:04 2021 [server] Peer Connection Initiated with [AF_INET]xx.xxx.xxx.25:443
    >     Wed Jan  6 10:28:05 2021 SENT CONTROL [server]: 'PUSH_REQUEST' (status=1)
    >     Wed Jan  6 10:28:05 2021 PUSH: Received control message: 'PUSH_REPLY,dhcp-option DNS xxx.xx.x.2,dhcp-option DNS 8.8.8.8,route
    > xxx.xx.x.0 255.255.0.0,route-gateway xxx.xx.x.129,topology subnet,ping
    > 1,ping-restart 20,ifconfig xxx.xx.x.130 255.255.255.224,peer-id
    > 0,cipher AES-256-GCM'
    >     Wed Jan  6 10:28:05 2021 OPTIONS IMPORT: timers and/or timeouts modified
    >     Wed Jan  6 10:28:05 2021 OPTIONS IMPORT: --ifconfig/up options modified
    >     Wed Jan  6 10:28:05 2021 OPTIONS IMPORT: route options modified
    >     Wed Jan  6 10:28:05 2021 OPTIONS IMPORT: route-related options modified
    >     Wed Jan  6 10:28:05 2021 OPTIONS IMPORT: --ip-win32 and/or --dhcp-option options modified
    >     Wed Jan  6 10:28:05 2021 OPTIONS IMPORT: peer-id set
    >     Wed Jan  6 10:28:05 2021 OPTIONS IMPORT: adjusting link_mtu to 1624
    >     Wed Jan  6 10:28:05 2021 OPTIONS IMPORT: data channel crypto options modified
    >     Wed Jan  6 10:28:05 2021 Outgoing Data Channel: Cipher 'AES-256-GCM' initialized with 256 bit key
    >     Wed Jan  6 10:28:05 2021 Incoming Data Channel: Cipher 'AES-256-GCM' initialized with 256 bit key
    >     Wed Jan  6 10:28:05 2021 ROUTE_GATEWAY 192.168.1.1/255.255.255.0 IFACE=eth0 HWADDR=xx:xx:xx:xx:xx:xx

TUN/TAP not created beyond this

I have been trying different approaches to fix this issue, but I couldn't a solution for it. How can I fix this issue? Any help will be highly appreciated.

I created it following - https://www.acmesystems.it/compile_linux_4_4_X_LTS and the used modprobe tun — MJ019, Jan 04 '21 at 16:14
oh. ok. Then which 'tunctl' command should I use to create the tun0? — MJ019, Jan 04 '21 at 16:37

score 1 · Answer 1 · answered Jan 04 '21 at 19:47

1

To create a tun0 interface owned by root do

sudo tunctl tun0

To create it with yourself as owner do

sudo tunctl -u $USER tun0

answered Jan 04 '21 at 19:47

stark

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hi @stark, I tried with is cmd, but still no 'tun0' was created when 'openvpn --congif....' – MJ019 Jan 05 '21 at 11:11

tun0: device not found

1 Answers1