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OpenVPN: dhclient が失敗する

tag-icon • tag-icon debian openvpn dhcp
OpenVPN: dhclient が失敗する

openvpn クライアントを起動し、dhclient tap0IP アドレスを取得するために実行すると、すべて正常に動作します。

同じコマンドがスクリプトから openvpn によって呼び出される場合 (upオプション):

#!/bin/sh
/sbin/dhclient tap0 || exit 1
exit 0

失敗します:

dhclient[30524]: Sending on   LPF/tap0/aa:aa:aa:12:23:e9
dhclient[30524]: Can't bind to dhcp address: Permission denied
dhclient[30524]: Please make sure there is no other dhcp server
dhclient[30524]: running and that there's no entry for dhcp or
dhclient[30524]: bootp in /etc/inetd.conf.   Also make sure you
dhclient[30524]: are not running HP JetAdmin software, which
openvpn[30517]: WARNING: Failed running command (--up/--down): external program exited with error status: 1
openvpn[30517]: Exiting due to fatal error
dhclient[30524]: includes a bootp server.
dhclient[30524]: 
dhclient[30524]: If you think you have received this message due to a bug rather
dhclient[30524]: than a configuration issue please read the section on submitting
dhclient[30524]: bugs on either our web page at www.isc.org or in the README file
dhclient[30524]: before submitting a bug.  These pages explain the proper
dhclient[30524]: process and the information we find helpful for debugging..
dhclient[30524]: 
dhclient[30524]: exiting.
systemd[1]: openvpn-client.service: Main process exited, code=exited, status=1/FAILURE

すべてが root として実行されるため、権限の問題は発生しないはずです。

答え1

スクリプトに「sudo」を入れて、openvpn を実行しているユーザーに対してパスワードなしで sudoers からの dhclient を許可してみてください。

また、conf で「script-security 2」を指定しましたか?

--script-security level [method]
          This  directive offers policy-level control over OpenVPN’s usage
          of external programs and scripts.  Lower level values  are  more
          restrictive,  higher  values  are more permissive.  Settings for
          level:

          0 -- Strictly no calling of external programs.
          1 -- (Default) Only call built-in executables such as  ifconfig,
          ip, route, or netsh.
          2  --  Allow  calling  of  built-in executables and user-defined
          scripts.
          3 -- Allow passwords to be passed to scripts  via  environmental
          variables (potentially unsafe).`

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