Openvz - pppd: Couldn't set tty to PPP discipline: Invalid argument

Ошибка:

Feb 1 13:16:55 vps111 pptpd[728]: CTRL: Client xxx.xxx.xx.xxx control connection finished
Feb 1 13:23:47 vps111 pppd[732]: pppd 2.4.5 started by root, uid 0
Feb 1 13:23:47 vps111 pppd[732]: Couldn't set tty to PPP discipline: Invalid argument
Feb 1 13:23:47 vps111 pppd[732]: Exit.

Решение - это подгрузить нужные модули ядра:

# modprobe ppp_async
# modprobe ppp_deflate
# modprobe ppp_mppe

Links:

http://pptpclient.sourceforge.net/howto-diagnosis.phtml#tty_einval