ioctl(3, DM_VERSION, {version=4.0.0, data_size=16384, flags=DM_EXISTS_FLAG} => {version=4.35.0, data_size=16384, flags=DM_EXISTS_FLAG}) = 0
stat("/dev/vg/lv20", {st_mode=S_IFBLK|0660, st_rdev=makedev(253, 18), ...}) = 0
stat("/dev/mapper/lv20", 0x7ffd1b0ce0d0) = -1 ENOENT (No such file or directory)
open("/dev/mapper", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 4
fstat(4, {st_mode=S_IFDIR|0755, st_size=460, ...}) = 0
getdents(4, /* 23 entries */, 32768)    = 992
stat("/dev/mapper/vg-lv15-real", {st_mode=S_IFBLK|0660, st_rdev=makedev(253, 18), ...}) = 0
close(4)                                = 0
ioctl(3, DM_DEV_STATUS, {version=4.0.0, data_size=16384, name="vg-lv15-real", flags=DM_EXISTS_FLAG} => {version=4.35.0, data_size=16384, name="vg-lv15-real", flags=DM_EXISTS_FLAG}) = -1 ENXIO (No such device or address)
write(2, "Device does not exist.", 22Device does not exist.)  = 22
write(2, "\n", 1
)                       = 1
write(2, "Command failed.", 15Command failed.)         = 15
write(2, "\n", 1
)                       = 1
close(3)                                = 0
exit_group(1)                           = ?
+++ exited with 1 +++