4.0.4: lxc-copy does nothing

[kloczek]

After create first container:

# lxc-ls -f
NAME   STATE   AUTOSTART GROUPS IPV4       IPV6 UNPRIVILEGED
fedora RUNNING 0         -      10.0.3.104 -    false

(which has been created on btrfs) I've been trying to clone/copy it
So I've executed:

# lxc-copy -n fedora -N fedora-test -s -B btrfs

But that command does nothing and even does not print any warnings or errors .. completly nothing (!! ?)
Man page is really enigmatic and using it is really hard figure oit what needs to be done. Am I doing that wrong way?
All what I want is just create clone of the existing zone with btrfs clone underneath.

On using strace I see only:

# strace -f lxc-copy -n fedora -N fedora-test -s -B btrfs
execve("/usr/bin/lxc-copy", ["lxc-copy", "-n", "fedora", "-N", "fedora-test", "-s", "-B", "btrfs"], 0x7ffc52a6c750 /* 26 vars */) = 0
brk(NULL)                               = 0x55b7a47ad000
arch_prctl(0x3001 /* ARCH_??? */, 0x7ffda8e90540) = -1 EINVAL (Invalid argument)
access("/etc/ld.so.preload", R_OK)      = -1 ENOENT (No such file or directory)
openat(AT_FDCWD, "/etc/ld.so.cache", O_RDONLY|O_CLOEXEC) = 3
fstat(3, {st_mode=S_IFREG|0644, st_size=239749, ...}) = 0
mmap(NULL, 239749, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f0a5c20c000
close(3)                                = 0
openat(AT_FDCWD, "/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\0\340\202\2\0\0\0\0\0"..., 832) = 832
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\0\300\4\0\0\0\330\1\0\0\0\0\0\0"..., 48, 848) = 48
pread64(3, "\4\0\0\0\24\0\0\0\3\0\0\0GNU\0\317Xfi\305\0100\254e\331\344\230\356\302\276\254"..., 68, 896) = 68
fstat(3, {st_mode=S_IFREG|0755, st_size=3226024, ...}) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f0a5c20a000
pread64(3, "\6\0\0\0\4\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0@\0\0\0\0\0\0\0"..., 784, 64) = 784
mmap(NULL, 1880736, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5c03e000
mprotect(0x7f0a5c064000, 1687552, PROT_NONE) = 0
mmap(0x7f0a5c064000, 1372160, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x26000) = 0x7f0a5c064000
mmap(0x7f0a5c1b3000, 311296, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x175000) = 0x7f0a5c1b3000
mmap(0x7f0a5c200000, 24576, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1c1000) = 0x7f0a5c200000
mmap(0x7f0a5c206000, 12960, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f0a5c206000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/liblxc.so.1", 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\20\321\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=665152, ...}) = 0
mmap(NULL, 653824, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5bf9e000
mmap(0x7f0a5bfaa000, 421888, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xc000) = 0x7f0a5bfaa000
mmap(0x7f0a5c011000, 163840, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x73000) = 0x7f0a5c011000
mmap(0x7f0a5c039000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x9a000) = 0x7f0a5c039000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libseccomp.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\320!\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=115488, ...}) = 0
mmap(NULL, 114752, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5bf81000
mprotect(0x7f0a5bf83000, 102400, PROT_NONE) = 0
mmap(0x7f0a5bf83000, 45056, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f0a5bf83000
mmap(0x7f0a5bf8e000, 53248, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xd000) = 0x7f0a5bf8e000
mmap(0x7f0a5bf9c000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1a000) = 0x7f0a5bf9c000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libselinux.so.1", 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\320\207\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=176656, ...}) = 0
mmap(NULL, 181736, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5bf54000
mmap(0x7f0a5bf5b000, 106496, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x7000) = 0x7f0a5bf5b000
mmap(0x7f0a5bf75000, 32768, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x21000) = 0x7f0a5bf75000
mmap(0x7f0a5bf7d000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x28000) = 0x7f0a5bf7d000
mmap(0x7f0a5bf7f000, 5608, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f0a5bf7f000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libutil.so.1", 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\360\23\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=23536, ...}) = 0
mmap(NULL, 16392, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5bf4f000
mmap(0x7f0a5bf50000, 4096, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1000) = 0x7f0a5bf50000
mmap(0x7f0a5bf51000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f0a5bf51000
mmap(0x7f0a5bf52000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f0a5bf52000
mmap(0x7f0a5bf53000, 8, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f0a5bf53000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libpthread.so.0", 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@\201\0\0\0\0\0\0"..., 832) = 832
pread64(3, "\4\0\0\0 \0\0\0\5\0\0\0GNU\0\1\0\0\300\4\0\0\0\30\0\0\0\0\0\0\0"..., 48, 792) = 48
pread64(3, "\4\0\0\0\24\0\0\0\3\0\0\0GNU\0\r:H \34T\315\347\335O\323\331\17z\223\360"..., 68, 840) = 68
fstat(3, {st_mode=S_IFREG|0755, st_size=304656, ...}) = 0
mmap(NULL, 135600, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5bf2d000
mmap(0x7f0a5bf34000, 65536, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x7000) = 0x7f0a5bf34000
mmap(0x7f0a5bf44000, 20480, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x17000) = 0x7f0a5bf44000
mmap(0x7f0a5bf49000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1b000) = 0x7f0a5bf49000
mmap(0x7f0a5bf4b000, 12720, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f0a5bf4b000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libcap.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\0p7\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=36944, ...}) = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f0a5bf2b000
mmap(NULL, 36920, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5bf21000
mmap(0x7f0a5bf24000, 12288, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0x7f0a5bf24000
mmap(0x7f0a5bf27000, 8192, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x6000) = 0x7f0a5bf27000
mmap(0x7f0a5bf29000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x7000) = 0x7f0a5bf29000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libgcc_s.so.1", 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\3605\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=108352, ...}) = 0
mmap(NULL, 107592, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5bf06000
mmap(0x7f0a5bf09000, 73728, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0x7f0a5bf09000
mmap(0x7f0a5bf1b000, 16384, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x15000) = 0x7f0a5bf1b000
mmap(0x7f0a5bf1f000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x18000) = 0x7f0a5bf1f000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libcrypto.so.1.1", 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\0\300\7\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=3082320, ...}) = 0
mmap(NULL, 3059344, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5bc1b000
mmap(0x7f0a5bc95000, 1753088, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x7a000) = 0x7f0a5bc95000
mmap(0x7f0a5be41000, 593920, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x226000) = 0x7f0a5be41000
mmap(0x7f0a5bed2000, 196608, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2b6000) = 0x7f0a5bed2000
mmap(0x7f0a5bf02000, 16016, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f0a5bf02000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libpcre2-8.so.0", 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`\"\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=612568, ...}) = 0
mmap(NULL, 610928, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5bb85000
mmap(0x7f0a5bb87000, 430080, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f0a5bb87000
mmap(0x7f0a5bbf0000, 167936, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x6b000) = 0x7f0a5bbf0000
mmap(0x7f0a5bc19000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x93000) = 0x7f0a5bc19000
close(3)                                = 0
openat(AT_FDCWD, "/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\0p\"\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=37392, ...}) = 0
mmap(NULL, 24688, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5bb7e000
mmap(0x7f0a5bb80000, 8192, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7f0a5bb80000
mmap(0x7f0a5bb82000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x4000) = 0x7f0a5bb82000
mmap(0x7f0a5bb83000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x4000) = 0x7f0a5bb83000
mmap(0x7f0a5bb84000, 112, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f0a5bb84000
close(3)                                = 0
openat(AT_FDCWD, "/lib64/libz.so.1", 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\0\3605\0\0\0\0\0\0"..., 832) = 832
fstat(3, {st_mode=S_IFREG|0755, st_size=103128, ...}) = 0
mmap(NULL, 102408, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7f0a5bb64000
mprotect(0x7f0a5bb67000, 86016, PROT_NONE) = 0
mmap(0x7f0a5bb67000, 57344, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x3000) = 0x7f0a5bb67000
mmap(0x7f0a5bb75000, 24576, PROT_READ, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x11000) = 0x7f0a5bb75000
mmap(0x7f0a5bb7c000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x17000) = 0x7f0a5bb7c000
mmap(0x7f0a5bb7d000, 8, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f0a5bb7d000
close(3)                                = 0
mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f0a5bb62000
mmap(NULL, 12288, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f0a5bb5f000
arch_prctl(ARCH_SET_FS, 0x7f0a5bb5f8c0) = 0
mprotect(0x7f0a5c200000, 12288, PROT_READ) = 0
mprotect(0x7f0a5bb7c000, 4096, PROT_READ) = 0
mprotect(0x7f0a5bb83000, 4096, PROT_READ) = 0
mprotect(0x7f0a5bf49000, 4096, PROT_READ) = 0
mprotect(0x7f0a5bc19000, 4096, PROT_READ) = 0
mprotect(0x7f0a5bed2000, 180224, PROT_READ) = 0
mprotect(0x7f0a5bf1f000, 4096, PROT_READ) = 0
mprotect(0x7f0a5bf29000, 4096, PROT_READ) = 0
mprotect(0x7f0a5bf52000, 4096, PROT_READ) = 0
mprotect(0x7f0a5bf7d000, 4096, PROT_READ) = 0
mprotect(0x7f0a5bf9c000, 4096, PROT_READ) = 0
mprotect(0x7f0a5c039000, 12288, PROT_READ) = 0
mprotect(0x55b7a34df000, 12288, PROT_READ) = 0
mprotect(0x7f0a5c272000, 4096, PROT_READ) = 0
munmap(0x7f0a5c20c000, 239749)          = 0
set_tid_address(0x7f0a5bb5fb90)         = 896724
set_robust_list(0x7f0a5bb5fba0, 24)     = 0
rt_sigaction(SIGRTMIN, {sa_handler=0x7f0a5bf34ba0, sa_mask=[], sa_flags=SA_RESTORER|SA_SIGINFO, sa_restorer=0x7f0a5bf41250}, NULL, 8) = 0
rt_sigaction(SIGRT_1, {sa_handler=0x7f0a5bf34c40, sa_mask=[], sa_flags=SA_RESTORER|SA_RESTART|SA_SIGINFO, sa_restorer=0x7f0a5bf41250}, NULL, 8) = 0
rt_sigprocmask(SIG_UNBLOCK, [RTMIN RT_1], NULL, 8) = 0
prlimit64(0, RLIMIT_STACK, NULL, {rlim_cur=8192*1024, rlim_max=RLIM64_INFINITY}) = 0
openat(AT_FDCWD, "/proc/sys/crypto/fips_enabled", O_RDONLY) = 3
read(3, "0\n", 2)                       = 2
close(3)                                = 0
access("/etc/system-fips", F_OK)        = -1 ENOENT (No such file or directory)
prctl(PR_CAPBSET_READ, CAP_MAC_OVERRIDE) = 1
prctl(PR_CAPBSET_READ, 0x30 /* CAP_??? */) = -1 EINVAL (Invalid argument)
prctl(PR_CAPBSET_READ, 0x28 /* CAP_??? */) = -1 EINVAL (Invalid argument)
prctl(PR_CAPBSET_READ, CAP_BLOCK_SUSPEND) = 1
prctl(PR_CAPBSET_READ, CAP_PERFMON)     = 1
prctl(PR_CAPBSET_READ, CAP_BPF)         = 1
statfs("/sys/fs/selinux", {f_type=SELINUX_MAGIC, f_bsize=4096, f_blocks=0, f_bfree=0, f_bavail=0, f_files=0, f_ffree=0, f_fsid={val=[0, 0]}, f_namelen=255, f_frsize=4096, f_flags=ST_VALID|ST_RELATIME}) = 0
statfs("/sys/fs/selinux", {f_type=SELINUX_MAGIC, f_bsize=4096, f_blocks=0, f_bfree=0, f_bavail=0, f_files=0, f_ffree=0, f_fsid={val=[0, 0]}, f_namelen=255, f_frsize=4096, f_flags=ST_VALID|ST_RELATIME}) = 0
brk(NULL)                               = 0x55b7a47ad000
brk(0x55b7a47ce000)                     = 0x55b7a47ce000
access("/etc/selinux/config", F_OK)     = 0
geteuid()                               = 0
openat(AT_FDCWD, "/etc/lxc/lxc.conf", O_RDONLY|O_CLOEXEC) = -1 ENOENT (No such file or directory)
geteuid()                               = 0
stat("/run", {st_mode=S_IFDIR|0755, st_size=1620, ...}) = 0
geteuid()                               = 0
mkdir("/", 0755)                        = -1 EEXIST (File exists)
mkdir("/run/", 0755)                    = -1 EEXIST (File exists)
mkdir("/run/lxc/", 0755)                = -1 EEXIST (File exists)
mkdir("/run/lxc/lock//", 0755)          = -1 EEXIST (File exists)
mkdir("/run/lxc/lock//var/", 0755)      = -1 EEXIST (File exists)
mkdir("/run/lxc/lock//var/lib/", 0755)  = -1 EEXIST (File exists)
mkdir("/run/lxc/lock//var/lib/lxc", 0755) = -1 EEXIST (File exists)
stat("/var/lib/lxc/fedora/config", {st_mode=S_IFREG|0640, st_size=781, ...}) = 0
openat(AT_FDCWD, "/run/lxc/lock//var/lib/lxc/.fedora", O_RDWR|O_CREAT|O_NOCTTY|O_NOFOLLOW|O_CLOEXEC, 0600) = 3
fcntl(3, F_OFD_SETLKW, {l_type=F_WRLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = 0
memfd_create(".lxc_config_file", MFD_CLOEXEC) = 4
openat(AT_FDCWD, "/var/lib/lxc/fedora/config", O_RDONLY|O_CLOEXEC) = 5
sendfile(4, 5, NULL, 2147479552)        = 781
write(4, "\0", 1)                       = 1
lseek(4, 0, SEEK_SET)                   = 0
mmap(NULL, 782, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_POPULATE, 4, 0) = 0x7f0a5c246000
stat("/usr/share/lxc/config/common.conf", {st_mode=S_IFREG|0644, st_size=2346, ...}) = 0
memfd_create(".lxc_config_file", MFD_CLOEXEC) = 6
openat(AT_FDCWD, "/usr/share/lxc/config/common.conf", O_RDONLY|O_CLOEXEC) = 7
sendfile(6, 7, NULL, 2147479552)        = 2346
write(6, "\0", 1)                       = 1
lseek(6, 0, SEEK_SET)                   = 0
mmap(NULL, 2347, PROT_READ|PROT_WRITE, MAP_SHARED|MAP_POPULATE, 6, 0) = 0x7f0a5c245000
stat("/usr/share/lxc/config/common.conf.d/", {st_mode=S_IFDIR|0755, st_size=12, ...}) = 0
openat(AT_FDCWD, "/usr/share/lxc/config/common.conf.d/", O_RDONLY|O_NONBLOCK|O_CLOEXEC|O_DIRECTORY) = 8
fstat(8, {st_mode=S_IFDIR|0755, st_size=12, ...}) = 0
getdents64(8, 0x55b7a47b14f0 /* 3 entries */, 32768) = 80
getdents64(8, 0x55b7a47b14f0 /* 0 entries */, 32768) = 0
close(8)                                = 0
close(7)                                = 0
close(6)                                = 0
munmap(0x7f0a5c245000, 2347)            = 0
getpid()                                = 896724
openat(AT_FDCWD, "/dev/urandom", O_RDONLY|O_CLOEXEC) = 6
fstat(6, {st_mode=S_IFCHR|0666, st_rdev=makedev(0x1, 0x9), ...}) = 0
ioctl(6, TCGETS, 0x7ffda8e8fec0)        = -1 EINVAL (Invalid argument)
read(6, "\17\321}\345\"\215\304\325\330\36\216s\27+\204Cne\\\264\361\373\327F\25\236g4\r\276\334\327"..., 4096) = 4096
close(6)                                = 0
getpid()                                = 896724
openat(AT_FDCWD, "/dev/urandom", O_RDONLY|O_CLOEXEC) = 6
fstat(6, {st_mode=S_IFCHR|0666, st_rdev=makedev(0x1, 0x9), ...}) = 0
ioctl(6, TCGETS, 0x7ffda8e8fe70)        = -1 EINVAL (Invalid argument)
read(6, "g\3364\351\246A^\333\3605%\342v\274\32n\354\351?\273\321c\320(G\332\2038\t\354\24\22"..., 4096) = 4096
close(6)                                = 0
close(5)                                = 0
close(4)                                = 0
munmap(0x7f0a5c246000, 782)             = 0
fcntl(3, F_OFD_SETLK, {l_type=F_UNLCK, l_whence=SEEK_SET, l_start=0, l_len=0}) = 0
close(3)                                = 0
openat(AT_FDCWD, "/var/lib/lxc/fedora/partial", O_RDWR|O_CLOEXEC) = -1 ENOENT (No such file or directory)
socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0) = 3
connect(3, {sa_family=AF_UNIX, sun_path=@"/var/lib/lxc/fedora/command"}, 30) = 0
getpid()                                = 896724
getuid()                                = 0
getgid()                                = 0
sendmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\4\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", iov_len=16}], msg_iovlen=1, msg_control=[{cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS, cmsg_data={pid=896724, uid=0, gid=0}}], msg_controllen=32, msg_flags=0}, MSG_NOSIGNAL) = 16
recvmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\0\0\0\0\0\0\0\0\206H?\0\0\0\0\0", iov_len=16}], msg_iovlen=1, msg_controllen=0, msg_flags=MSG_CMSG_CLOEXEC}, MSG_CMSG_CLOEXEC) = 16
close(3)                                = 0
stat("/var/lib/lxc/fedora/config", {st_mode=S_IFREG|0640, st_size=781, ...}) = 0
stat("/var/lib/lxc/fedora/config", {st_mode=S_IFREG|0640, st_size=781, ...}) = 0
socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0) = 3
connect(3, {sa_family=AF_UNIX, sun_path=@"/var/lib/lxc/fedora/command"}, 30) = 0
getpid()                                = 896724
getuid()                                = 0
getgid()                                = 0
sendmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\3\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", iov_len=16}], msg_iovlen=1, msg_control=[{cmsg_len=28, cmsg_level=SOL_SOCKET, cmsg_type=SCM_CREDENTIALS, cmsg_data={pid=896724, uid=0, gid=0}}], msg_controllen=32, msg_flags=0}, MSG_NOSIGNAL) = 16
recvmsg(3, {msg_name=NULL, msg_namelen=0, msg_iov=[{iov_base="\0\0\0\0\0\0\0\0\2\0\0\0\0\0\0\0", iov_len=16}], msg_iovlen=1, msg_controllen=0, msg_flags=MSG_CMSG_CLOEXEC}, MSG_CMSG_CLOEXEC) = 16
close(3)                                = 0
exit_group(1)                           = ?
+++ exited with 1 +++

[yearski]

I think the root issue to be addressed is that lxc-copy can fail without useable log output. For example:

 /var/lib/lxc % lxc-copy -n archlinux-base -N www -B overlayfs -s

Failed silently. Retrying the command increasing log priority level with -l INFO:

/var/lib/lxc % lxc-copy -n archlinux-base -N www -B overlayfs -s -l INFO
lxc-copy: archlinux-base: storage/overlay.c: ovl_clonepaths: 244 Invalid argument - overlay clone of btrfs container is not yet supported
lxc-copy: archlinux-base: storage/storage.c: storage_copy: 412 Failed creating new paths for clone of "/var/lib/lxc/archlinux-base/rootfs"
lxc-copy: archlinux-base: lxccontainer.c: copy_storage: 3584 Error copying storage.
lxc-copy: archlinux-base: tools/lxc_copy.c: do_clone: 358 Failed to clonelxc-copy: base: tools/lxc_copy.c: do_clone: 358 Failed to clone

In my case, I made a simple copy paste error from another project, the -B overlayfs option should have been btrfs. I think Error copying storage should have been raised to ERROR level.

[yearski]

@kloczek You might also check to see if the snapshot was created somewhere unexpected. I found this in Stéphane's blog
https://stgraber.org/2013/12/27/lxc-1-0-container-storage/. It's a bit old so may not still apply, but I didn't find it documented elsewhere (casually searching).

Standard paths
One quick word with the way LXC usually works and where it’s storing its files:

- /var/lib/lxc (default location for containers)
- /var/lib/lxcsnap (default location for snapshots)
- /var/cache/lxc (default location for the template cache)
- $HOME/.local/share/lxc (default location for unprivileged containers)
- $HOME/.local/share/lxcsnap (default location for unprivileged snapshots)
- $HOME/.cache/lxc (default location for unprivileged template cache)

Otherwise, try running it again increasing the log level with -l INFO.

[yearski]

Another example of a silent failure that I think should log at a level higher than INFO:

lxc-copy: archlinux-base: lxccontainer.c: do_lxcapi_clone: 3785 error: Original container (archlinux-base) is running. Use --allowrunning if you want to force a snapshot of the running container.
lxc-copy: archlinux-base: tools/lxc_copy.c: do_clone: 358 Failed to clone

[yearski]

Is this the same issue as #4405 resolved by #4421?

I verified that my two examples are resolved. I suspect the silent "is running" error was at fault for OP

# lxc-ls -f
NAME   STATE   AUTOSTART GROUPS IPV4       IPV6 UNPRIVILEGED
fedora RUNNING 0         -      10.0.3.104 -    false