我有一個 docker 容器，我正在嘗試在其中運行 pppd。主機內核具有CONFIG_PPP=y.我正在像這樣設定 ppp 設備：
mkdir /run/container/dev
mknod /run/container/dev c 108 0
... add some more devices here ...
然後我啟動卷安裝量為 的容器/run/container/dev:/dev。容器以 root 身分執行--privileged，且容器內的進程以 root 身分執行。
當我嘗試在容器內執行 pppd 時，它失敗了：
/ # pppd
Couldn't open the /dev/ppp device: Operation not permitted
pppd: Sorry - this system lacks PPP kernel support
strace表示問題出EPERM在嘗試開啟時/dev/ppp：
openat(AT_FDCWD, "/dev/ppp", O_RDWR|O_LARGEFILE) = -1 EPERM (Operation not permitted)
getpid() = 76
sendto(3, "<27>Jul 14 09:55:08 pppd[76]: Co"..., 89, 0, NULL, 0) = -1 ENOTCONN (Socket not connected)
connect(3, {sa_family=AF_UNIX, sun_path="/dev/log"}, 12) = -1 EPROTOTYPE (Protocol wrong type for socket)
write(1, "Couldn't open the /dev/ppp devic"..., 58Couldn't open the /dev/ppp device: Operation not permitted) = 58
write(1, "\n", 1
) = 1
writev(2, [{iov_base="pppd: Sorry - this system lacks "..., iov_len=52}, {iov_base=NULL, iov_len=0}], 2pppd: Sorry - this system lacks PPP kernel support
) = 52
getpid() = 76
sendto(3, "<27>Jul 14 09:55:08 pppd[76]: So"..., 75, 0, NULL, 0) = -1 ENOTCONN (Socket not connected)
connect(3, {sa_family=AF_UNIX, sun_path="/dev/log"}, 12) = -1 EPROTOTYPE (Protocol wrong type for socket)
exit_group(4) = ?
我在這裡缺少什麼？
答案1
--device-cgroup-rule="c 108:0 rwm"最終在 docker 命令列上找到了這一點。