[Asterisk-Users] (for FC3 too) Unable to open master device '/dev/zap/ctl'

[Doug Campbell]

>>You are right! If his distro is using udev it might dynamically create
>>the zap devices with the wrong set of permissions.

Alternately, it could be that /sbin/ztcfg assumes that the devices
are available immediately, which they are not on a udev system like
Fedora Core 3 (and others).

I have found that I can overcome this error by just unloading the
module and then loading it again:

  modprobe wcfxo
  rmmod wcfxo
  modprobe wcfxo

The second modprobe always works for me with no errors.

If one were ambitious and had the time, one could change
ztcfg.c to wait for the availability of the device file
before trying to open it.

Doug