[Freeipa-devel] Adding a User-Managed YubiKey Hardware Token valueerror: no backend available

[Alexander Bokovoy]

On pe, 24 helmi 2017, Oucema Bellagha wrote:
>while I'm trying to add an ipa token to freeipa server: ipa otptoken-add-yubikey --slot=2
>I got the following error:
>
>ipa: ERROR: non-public: ValueError: No backend available
>Traceback (most recent call last):
>  File "/usr/lib/python2.7/site-packages/ipalib/backend.py", line 137, in execute
>    result = self.Command[_name](*args, **options)
>  File "/usr/lib/python2.7/site-packages/ipalib/frontend.py", line 449, in __call__
>    return self.__do_call(*args, **options)
>  File "/usr/lib/python2.7/site-packages/ipalib/frontend.py", line 477, in __do_call
>    ret = self.run(*args, **options)
>  File "/usr/lib/python2.7/site-packages/ipalib/frontend.py", line 800, in run
>    return self.forward(*args, **options)
>  File "/usr/lib/python2.7/site-packages/ipaclient/plugins/otptoken_yubikey.py", line 120, in forward
>    yk = yubico.find_yubikey()
>  File "/usr/lib/python2.7/site-packages/yubico/yubikey.py", line 229, in find_key
>    YK = YubiKeyUSBHID(debug=debug, skip=skip)
>  File "/usr/lib/python2.7/site-packages/yubico/yubikey_usb_hid.py", line 165, in __init__
>    if not self._open(skip):
>  File "/usr/lib/python2.7/site-packages/yubico/yubikey_usb_hid.py", line 447, in _open
>    usb_device = self._get_usb_device(skip)
>  File "/usr/lib/python2.7/site-packages/yubico/yubikey_usb_hid.py", line 497, in _get_usb_device
>    find_all=True, idVendor=_YUBICO_VID)]
>  File "/usr/lib/python2.7/site-packages/usb/core.py", line 864, in find
>    raise ValueError('No backend available')
>ValueError: No backend available
>ipa: ERROR: an internal error has occurred
>
>how can I fix this?
Install actual libusb package?

pyusb is designed to work against various usb library implementations.
In Fedora there are at least two: libusbx and libusb. Install one of
them.

What the following small python script does return on your system?

------
from usb.libloader import locate_library
print locate_library(('usb-1.0', 'libusb-1.0', 'usb'))
print locate_library(('usb-0.1', 'libusb-0.1', 'usb'))
-------


-- 
/ Alexander Bokovoy