You need to rerun with an "strace -f". That way it will also strace the fork's one of which it appears to be waiting on. On Mon, May 30, 2022 at 1:52 AM Abhishek Agarwal < mragarwal.developer@gmail.com> wrote: > When a kubernetes pod is scheduled on the node having lvm2 libraries > already installed and trying to run lvm commands using those node binaries > from inside the pod container, the commands hang and are waiting on > something to complete. Although when ctrl+c is pressed the terminal session > resumes and checking the final code for the execution returns a "0" error > code and the commands operation is also carried out successfully. > > > Below is the command output and strace for the command:- > > strace of lvcreate on the pod container scheduled on the node where lvm2 > binaries are present: > # strace /sbin/lvm-eg/lvcreate -n test-lv -L 1G shared-vg > execve("/sbin/lvm-eg/lvcreate", ["/sbin/lvm-eg/lvcreate", "-n", "test-lv", > "-L", "1G", "shared-vg"], 0x7ffe7d7a6c98 /* 37 vars */) = 0 > brk(NULL) = 0x55d196f41000 > arch_prctl(0x3001 /* ARCH_??? */, 0x7ffdd8247a80) = -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=8679, ...}) = 0 > mmap(NULL, 8679, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f0d37895000 > close(3) = 0 > openat(AT_FDCWD, "/lib/x86_64-linux-gnu/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\360A\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\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32, > 848) = 32 > pread64(3, > "\4\0\0\0\24\0\0\0\3\0\0\0GNU\0\237\333t\347\262\27\320l\223\27*\202C\370T\177"..., > 68, 880) = 68 > fstat(3, {st_mode=S_IFREG|0755, st_size=2029560, ...}) = 0 > mmap(NULL, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = > 0x7f0d37893000 > 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\20\0\0\0\5\0\0\0GNU\0\2\0\0\300\4\0\0\0\3\0\0\0\0\0\0\0", 32, > 848) = 32 > pread64(3, > "\4\0\0\0\24\0\0\0\3\0\0\0GNU\0\237\333t\347\262\27\320l\223\27*\202C\370T\177"..., > 68, 880) = 68 > mmap(NULL, 2037344, PROT_READ, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = > 0x7f0d376a1000 > mmap(0x7f0d376c3000, 1540096, PROT_READ|PROT_EXEC, > MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x22000) = 0x7f0d376c3000 > mmap(0x7f0d3783b000, 319488, PROT_READ, > MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x19a000) = 0x7f0d3783b000 > mmap(0x7f0d37889000, 24576, PROT_READ|PROT_WRITE, > MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x1e7000) = 0x7f0d37889000 > mmap(0x7f0d3788f000, 13920, PROT_READ|PROT_WRITE, > MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7f0d3788f000 > close(3) = 0 > arch_prctl(ARCH_SET_FS, 0x7f0d37894580) = 0 > mprotect(0x7f0d37889000, 16384, PROT_READ) = 0 > mprotect(0x55d196662000, 8192, PROT_READ) = 0 > mprotect(0x7f0d378c5000, 4096, PROT_READ) = 0 > munmap(0x7f0d37895000, 8679) = 0 > getuid() = 0 > getgid() = 0 > getpid() = 19163 > rt_sigaction(SIGCHLD, {sa_handler=0x55d196657c30, sa_mask=~[RTMIN RT_1], > sa_flags=SA_RESTORER, sa_restorer=0x7f0d376e40c0}, NULL, 8) = 0 > geteuid() = 0 > brk(NULL) = 0x55d196f41000 > brk(0x55d196f62000) = 0x55d196f62000 > getppid() = 19160 > stat("/", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 > stat(".", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0 > openat(AT_FDCWD, "/sbin/lvm-eg/lvcreate", O_RDONLY) = 3 > fcntl(3, F_DUPFD, 10) = 10 > close(3) = 0 > fcntl(10, F_SETFD, FD_CLOEXEC) = 0 > geteuid() = 0 > getegid() = 0 > rt_sigaction(SIGINT, NULL, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, > 8) = 0 > rt_sigaction(SIGINT, {sa_handler=0x55d196657c30, sa_mask=~[RTMIN RT_1], > sa_flags=SA_RESTORER, sa_restorer=0x7f0d376e40c0}, NULL, 8) = 0 > rt_sigaction(SIGQUIT, NULL, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, > 8) = 0 > rt_sigaction(SIGQUIT, {sa_handler=SIG_DFL, sa_mask=~[RTMIN RT_1], > sa_flags=SA_RESTORER, sa_restorer=0x7f0d376e40c0}, NULL, 8) = 0 > rt_sigaction(SIGTERM, NULL, {sa_handler=SIG_DFL, sa_mask=[], sa_flags=0}, > 8) = 0 > rt_sigaction(SIGTERM, {sa_handler=SIG_DFL, sa_mask=~[RTMIN RT_1], > sa_flags=SA_RESTORER, sa_restorer=0x7f0d376e40c0}, NULL, 8) = 0 > read(10, "#!/bin/sh\npath=$(/sbin/lvm-eg/ge"..., 8192) = 79 > pipe([3, 4]) = 0 > clone(child_stack=NULL, > flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, > child_tidptr=0x7f0d37894850) = 19164 > close(4) = 0 > read(3, "/usr/sbin/lvcreate\n", 128) = 19 > --- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=19164, si_uid=0, > si_status=0, si_utime=0, si_stime=0} --- > rt_sigreturn({mask=[]}) = 19 > read(3, "", 128) = 0 > close(3) = 0 > wait4(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0, NULL) = 19164 > stat("/usr/local/sbin/chroot", 0x7ffdd8247710) = -1 ENOENT (No such file > or directory) > stat("/usr/local/bin/chroot", 0x7ffdd8247710) = -1 ENOENT (No such file or > directory) > stat("/usr/sbin/chroot", {st_mode=S_IFREG|0755, st_size=43352, ...}) = 0 > clone(child_stack=NULL, > flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, > child_tidptr=0x7f0d37894850) = 19168 > wait4(-1, ^Cstrace: Process 19163 detached > > > # ^C > > `lvs` output on the node after pressing ctrl+c on the pod > container's terminal: > ubuntu@ip-172-31-85-197:~$ sudo lvs > LV VG Attr LSize Pool Origin Data% > Meta% Move Log Cpy%Sync Convert > test-lv shared-vg -wi-a----- 1.00g > > If ctrl+c is not pressed and trying to see the above output on the node > also hangs until the pod operation is interrupted. > _______________________________________________ > linux-lvm mailing list > linux-lvm@redhat.com > https://listman.redhat.com/mailman/listinfo/linux-lvm > read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/ >