当我运行程序时，出现挂载错误：
[root@host ~]# ip vrf exec wan1 /usr/sbin/ssh [email protected]
Failed to mount cgroup2: No such file or directory
我知道我的内核支持 cgroup2：
[root@host network-scripts]# cat /proc/filesystems
nodev sysfs
nodev rootfs
nodev ramfs
nodev bdev
nodev proc
nodev cpuset
nodev cgroup
nodev cgroup2
nodev tmpfs
nodev devtmpfs
nodev configfs
nodev debugfs
nodev tracefs
nodev securityfs
nodev sockfs
nodev dax
nodev bpf
nodev pipefs
nodev hugetlbfs
nodev devpts
nodev autofs
nodev pstore
nodev efivarfs
nodev mqueue
nodev selinuxfs
xfs
vfat
这是失败安装的踪迹：
[root@host tmp]# strace -e trace=mount ip vrf exec wan1 /usr/sbin/ssh [email protected]
mount("none", "/var/run/cgroup2", "cgroup2", 0, NULL) = -1 ENOENT (No such file or directory)
Failed to mount cgroup2: No such file or directory
+++ exited with 1 +++
[root@host tmp]#
我有一个空目录：
[root@host tmp]# ls -la /var/run/cgroup2
total 0
drwxr-xr-x. 2 root root 40 Jul 31 12:53 .
drwxr-xr-x. 27 root root 800 Jul 31 13:25 ..
[root@host tmp]#
知道我为什么会收到这个错误吗？我在 Centos 7 上运行，内核为 4.17.10-1
谢谢你的帮助
[root@host tmp]# strace ip vrf exec wan1 /usr/sbin/ssh [email protected]
execve("/usr/sbin/ip", ["ip", "vrf", "exec", "wan1", "/usr/sbin/ssh", "[email protected]"], [/* 25 vars */]) = 0
brk(NULL) = 0x1714000
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa21313c000
access("/etc/ld.so.preload", R_OK) = 0
open("/etc/ld.so.preload", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
close(3) = 0
open("/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=32868, ...}) = 0
mmap(NULL, 32868, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fa213133000
close(3) = 0
open("/lib64/libdl.so.2", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0`\16\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=19776, ...}) = 0
mmap(NULL, 2109744, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fa212d18000
mprotect(0x7fa212d1a000, 2097152, PROT_NONE) = 0
mmap(0x7fa212f1a000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7fa212f1a000
close(3) = 0
open("/lib64/libc.so.6", O_RDONLY|O_CLOEXEC) = 3
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0P%\2\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=2173512, ...}) = 0
mmap(NULL, 3981792, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fa21294b000
mprotect(0x7fa212b0e000, 2093056, PROT_NONE) = 0
mmap(0x7fa212d0d000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1c2000) = 0x7fa212d0d000
mmap(0x7fa212d13000, 16864, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fa212d13000
close(3) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa213132000
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa213130000
arch_prctl(ARCH_SET_FS, 0x7fa213130740) = 0
mprotect(0x7fa212d0d000, 16384, PROT_READ) = 0
mprotect(0x7fa212f1a000, 4096, PROT_READ) = 0
mprotect(0x669000, 4096, PROT_READ) = 0
mprotect(0x7fa21313d000, 4096, PROT_READ) = 0
munmap(0x7fa213133000, 32868) = 0
socket(AF_NETLINK, SOCK_RAW|SOCK_CLOEXEC, NETLINK_ROUTE) = 3
setsockopt(3, SOL_SOCKET, SO_SNDBUF, [32768], 4) = 0
setsockopt(3, SOL_SOCKET, SO_RCVBUF, [1048576], 4) = 0
setsockopt(3, SOL_NETLINK, 11, [1], 4) = 0
bind(3, {sa_family=AF_NETLINK, pid=0, groups=00000000}, 12) = 0
getsockname(3, {sa_family=AF_NETLINK, pid=1736, groups=00000000}, [12]) = 0
sendmsg(3, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000}, msg_iov(1)=[{",\0\0\0\22\0\1\0\347\305`[\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"..., 44}], msg_controllen=0, msg_flags=0}, 0) = 44
recvmsg(3, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000}, msg_iov(1)=[{NULL, 0}], msg_controllen=0, msg_flags=MSG_TRUNC}, MSG_PEEK|MSG_TRUNC) = 1316
brk(NULL) = 0x1714000
brk(0x1735000) = 0x1735000
brk(NULL) = 0x1735000
recvmsg(3, {msg_name(12)={sa_family=AF_NETLINK, pid=0, groups=00000000}, msg_iov(1)=[{"$\5\0\0\20\0\0\0\347\305`[\310\6\0\0\0\0\1\0\6\0\0\0\301\4\1\0\0\0\0\0"..., 1316}], msg_controllen=0, msg_flags=0}, 0) = 1316
open("/proc/mounts", O_RDONLY) = 4
fstat(4, {st_mode=S_IFREG|0444, st_size=0, ...}) = 0
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa21313b000
read(4, "sysfs /sys sysfs rw,seclabel,nos"..., 1024) = 1024
read(4, "0 0\ncgroup /sys/fs/cgroup/pids c"..., 1024) = 1024
read(4, "emd-1 /proc/sys/fs/binfmt_misc a"..., 1024) = 580
read(4, "", 1024) = 0
read(4, "", 1024) = 0
close(4) = 0
munmap(0x7fa21313b000, 4096) = 0
stat("/var", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
stat("/var/run", {st_mode=S_IFDIR|0755, st_size=800, ...}) = 0
stat("/var/run/cgroup2", {st_mode=S_IFDIR|0755, st_size=40, ...}) = 0
mount("none", "/var/run/cgroup2", "cgroup2", 0, NULL) = -1 ENOENT (No such file or directory)
write(2, "Failed to mount cgroup2: No such"..., 51Failed to mount cgroup2:No such file or directory) = 51
exit_group(1) = ?
+++ exited with 1 +++
答案1
根据您的 systemd 版本，这可能是一个错误。尝试运行带有
UNIFIED_CGROUP_HIERARCHY=no前缀的命令，即
[root@host ~]# UNIFIED_CGROUP_HIERARCHY=no ip vrf exec wan1 /usr/sbin/ssh [email protected]
这将导致 systemd 回退到混合或完整的传统 cgroup 层次结构。请参阅https://www.freedesktop.org/software/systemd/man/systemd.html#systemd.unified_cgroup_hierarchy