Re: [Openvpn-users] trouble with tun/tap driver

[Sean L. <me...@se...>]

Hello,

Bishop, you were correct - My /usr/include/linux dir had contents 
inconsistent with /usr/src/linux/include/linux (thanks red-hat!).  I 
fixed this, rebuilt and was on my way.   Now that I have it working, I 
must say it is excellent, and ideal for my purposes.  Thanks for your 
help and thank you James for help earlier and this great free software!

Sean

bishop wrote:

> James Yonan wrote:
>
>>> Hi James,
>>>
>>> Thank you for your prompt and detailed reply.  What was happening
>>> earlier was that I built openvpn first, then realized I needed to build
>>> the tun/tap kernel module, so built that and then rebuilt openvpn - but
>>> configure (god bless it) used the cached result of NOT finding 
>>> if_tun.h.
>>>  I cleared configure's cache and rebuilt it again - this time it found
>>> "tun/tap v1.4".  Now I'm onto a new set of problems though.  Now I get:
>>>
>>> 34: Cannot ioctl TUNSETIFF tun: File descriptor in bad state (errno=77)
>>
>>
>>
>> Though I've never seen this error personally, it has been talked about
>> extensively on the vtun list (another tunneling daemon that uses the 
>> TUN/TAP
>> driver).
>>
>> Go to http://sourceforge.net/mailarchive/forum.php?forum_id=1826
>>
>> and search for "bad state".
>>
>> It appears to be caused by a mismatch between the tun/tap kernel 
>> module and
>> the kernel itself.
>>
>> What kernel version are you using?
>>
>> Because in versions 2.4.6 and higher, the TUN/TAP module is integral 
>> to the
>> kernel -- if you try to build an external version of the module, 
>> rather than
>> using the one already bundled, it will likely fail.
>
>
> Also I've read a few posts that suggest that /usr/src/linux needs to 
> point to headers that match the running kernel.  Depending on what 
> Sean has, it may be worthwhile to ensure all the various versions 
> (kernel/headers/tunTap) all match.
>
> [insert pro-RPM/Deb rant here]
>
>  - bish
>
>