FATAL: cannot allocate TUN/TAP dev dynamically about android-openvpn-settings HOT 30 CLOSED

I followed this tutorial to install openVPN files on my device.
http://alldroid.org/threads/15594-OpenVPN-on-Milestone-%5BRoot-amp-Busybox-Requi
red%5D

Before with Tunnel droid, you could specify a path for the tun.ko file.
Now as the tutorial say, everytime you reboot, you have to type the following 
command
line : insmod /system/lib/modules/tun.ko
Using "adb shell".

Otherwise you have the error described above.

This cannot be included in the app ?

Thanks in advance

@celestin.masse

thanx for your help

I've inserted tun.ko file into the /system/lib/modules, thus while I type the 
insmod 
command line you've mentioned above, it returns: can't insert file 
/system/lib/modules/tun.ko file exists.

That means I've acquired the tun.ko in the lib/modules, but still got that 
error 
while launch the OpevVPN via openvpn settings.

Here is what I did :

Follow the tutorial
Get the files from the zip package.
When it says : (mtdblock6 might be 7 for some devices)
6 are for EU devices and 7 for US one.
Not sure that it changes anything but it's better to know it.
Then the tutorial have reboot step.
And after that come the command :
insmod /system/lib/modules/tun.ko


After that it was still not OK, but I found from the same developper, an 
application
named OpenVPN installer : http://code.google.com/p/android-openvpn-installer/
I installed this app by telling it for the first path : /system/bin
and /system/xbin for the second one.
Reboot the phone, go to adb shell>> su then the magic command line come :
insmod /system/lib/modules/tun.ko

After that I finish the tutorial by creating the links :

mount -o remount,rw -t yaffs2 /dev/block/mtdblock6 /system
mkdir /system/xbin
cd /system/xbin
ln -s /data/busybox/ifconfig ifconfig
ln -s /data/busybox/route route
mount -o remount,ro -t yaffs2 /dev/block/mtdblock6 /system

then it works.
If not, retry the magic command.

But the annoying thing is that you have to type :
the insmod /system/lib/modules/tun.ko command after every reboot using adb shell
And that was done before by tunnel droid but since the merge this feature 
disappeared.

Regards

@celestin.masse

Thx bud

But I managed to find an older version of TunnelDroid to use right now...So I'm 
expected to see OpenVPNSettings will get more rich featured.

Thanks in advance!

Added tun settings with settings for modprobe/insmod and path to tun module.
Could someone please verify it works?

@friedrich.schaeuffelhut

It works

thanx

btw, what's the difference between insmod and modprobe method?

@ss1271, It works for you ?

What are your settings ?
For me, using insmod and specifying the path /system/lib/modules/tun.ko is not 
working.
Really weird.

@celestin.masse
yup
it works
i'm using modprobe and specifying the path /system/lib/modules/tun.ko .
My devices didn't have the tun.ko file, because it loaded with official rom 
only, but I 
managed to find an usable one and put into /system/lib/modules after it was 
rooted.

@celestin.masse

UPDATE：
both modprobe and insmod working right now.

@ss1271

It must be my tun.ko file because none of the modprobe and insmod are working 
on my
phone. Where did you get yours ?

Are you also trying to go through the great firewall on your milestone ?
I say that because I saw a twitter app from you including proxy settings

@celestin.masse

I get my tun.ko from this place: http://orz.se/3Y6

works for my official rom 2.1-update1

As for that twitter app...I must say I have to hault that project because of my 
poor 
java knowledge , lol ：）

@ss1271

I get mine from this website also.
Weird that it doesn't work on my device which seems to be the same as yours.

@celestin.masse

Have you set the tun.ko's permission correctly if you put it into 
/system/lib/modules?

That may be the problem, I didn't adjust the permission settings there.

Can you have a look to that log, showing the permission settings for my tun.ko 
and a
few command to try to replace it.

Regards

That may be the problem, I didn't adjust the permission settings there.

Can you have a look to that log, showing the permission settings for my tun.ko 
and a
few command to try to replace it.

Regards

@celestin.masse

seems you are trying to grant 777 permission to this file.
this file's permission should be 644 just as the same as other files in this 
folder.

and before you use chmod command, you should remount this folder to make it 
writable.

If you feel not convenient to use command line on terminal, why not try root 
explorer 
(Paid apps)?

@ss1271

I just tried to chmod it.
I took the 777 permission randomly.
The fact that I can't write is due to the fact that forgot to mount it :(
You are right.

I feel convenient to use command line on the terminal. I use adb shell from my
computer or terminal emulator on the phone.

All right then.
I changed my tun.ko file, mount the folder again, change permission to 644.
Then it's working using insmod.

Perfect !
The version of the file seemed to be wrong.

Here is a new version of OpenVPN-Settings with tun parameters and fixes in the 
shell
communication. Sometimes the modprobe or insmod might have been discarded by 
the shell.
Could you please verify it works?

Issue 17 has been merged into this issue.

Seems to be solved now

@vandeplas.christophe

Well, the VPN connection seemed be disconnected automatically when not use for 
a while, 
can it be always online?

There is no feature disconnecting the tunnel. The tunnel should always be 
online. If
the problem persists please open a new bug.

Hi, please HELP =)!

I just was able to install, and I keep recieving the tun error, maybe is the 
wrong tun.ko, I even changed the permisions on it... is in insmod, but no 
luck!, im on android 2.1, rooted by paul @ modaco, original firmware...I dont 
know if I have busybox intalled, i asume i do because i can use openvpn 
settings gui...

Thanks in advance! I have 7 days left before i start paying to strongvpn to try 
to bypass the chinese greatwall

@yojosefo Hello, since this issue was marked as "fixed", would you please send 
me an E-mail privately? And I'll help you.

@yoyosefo : If you want to bypass the Great firewall, I'd suggest to go for 
L2TP or PPTP VPN, I am also trying to bypass it, but the openvpn technology is 
not working for me.

this issue is occurring in CyanogenMod 6.0rc1. I'm adjusting a bunch of 
settings and will double-check all the permissions when I get a chance tomorrow.

I had the same issue, installed a Chevyno1 kernel, seems to work now, at least 
it gets connected with the config file that I setup. No luck getting OpenVPN to 
work over 3G, need to research further.

I have Froyo in my Milestone, can i apply the same procedure? and im also 
getting     FATAL: cannot allocate TUN/TAP dev dynamically

I've also seen this and similar issues. Seems that it is quite easy
to get things installed into the wrong path. The only way for me to figure it 
out was to install the android development tools, and run adb shell.

This gives a way to test various things:
1. type 'adb shell' from your command line, now you're connected to your phone
2. type 'su'. If this works, your device is succesfully rooted.
3. type 'lsmod'. If this doesn't show something with 'tun', that driver is not 
loaded.
4. try out 'insmod /system/modules/tun.ko'. If this works, then you know what 
to fill in openVPN-settings/advanced/tun module settings.
5. 'which openvpn'
This gives you the path where openvpn is installed. Fill this in the 'advanced' 
menu of openVPN-settings.

6. Test your openvpn by hand: 
  cd /sdcard/openvpn
  openvpn client.conf &
(this runs openvpn in background, so now you can test your connection:)
  ping 8.8.8.8   # googles dns server. if it connects you have internet acces
  route  # shows you some gateways, try to ping them.

Hope this helps someone. I did end up compiling and installing openVPN-settings 
from source myself, but that shouldn't make a difference.

So for me the tool works, once I figured out the correct settings.

Sounds like a plan, but I'm new to Android.
How does one get to a command prompt?