Hi all. I currently try to start conntrackd to test it. CentOS release 6.3 (Final) Linux lb1.local 2.6.32-279.11.1.el6.x86_64 #1 SMP Tue Oct 16 15:57:10 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux This is a VirtualBox vm. I try: /usr/sbin/conntrackd -C /etc/conntrackd/conntrackd.conf -d My config: [root at lb1 log]# egrep -v '^\s*#|^$' /etc/conntrackd/conntrackd.conf | less Sync { Mode FTFW { } UDP { IPv4_address 192.168.100.11 IPv4_Destination_Address 192.168.100.12 Port 3780 SndSocketBuffer 1249280 RcvSocketBuffer 1249280 Checksum on } Options { } } General { Nice -20 HashSize 32768 HashLimit 131072 LogFile on LockFile /var/lock/conntrack.lock UNIX { Path /var/run/conntrackd.ctl Backlog 20 } NetlinkBufferSize 2097152 NetlinkBufferSizeMaxGrowth 8388608 Filter From Kernelspace { Protocol Accept { TCP } Address Ignore { IPv4_address 127.0.0.1 # loopback IPv4_address 192.168.100.11 # virtual IP 1 IPv4_address 192.168.100.12 # virtual IP 2 IPv4_address 10.0.2.111 IPv4_address 10.0.2.112 } State Accept { ESTABLISHED CLOSED TIME_WAIT CLOSE_WAIT for TCP } } } With strace (I haven't found an obvious problem in its output): strace /usr/sbin/conntrackd -C /etc/conntrackd/conntrackd.conf -d execve("/usr/sbin/conntrackd", ["/usr/sbin/conntrackd", "-C", "/etc/conntrackd/conntrackd.conf", "-d"], [/* 27 vars */]) = 0 brk(0) = 0x1c57000 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29ca4d000 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory) open("/etc/ld.so.cache", O_RDONLY) = 3 fstat(3, {st_mode=S_IFREG|0644, st_size=25665, ...}) = 0 mmap(NULL, 25665, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7fa29ca46000 close(3) = 0 open("/usr/lib64/libnetfilter_conntrack.so.3", O_RDONLY) = 3 read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0 at G\0\0\0\0\0\0"..., 832) = 832 fstat(3, {st_mode=S_IFREG|0755, st_size=85240, ...}) = 0 mmap(NULL, 2180848, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fa29c61a000 mprotect(0x7fa29c62d000, 2097152, PROT_NONE) = 0 mmap(0x7fa29c82d000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x13000) = 0x7fa29c82d000 close(3) = 0 open("/usr/lib64/libnfnetlink.so.0", O_RDONLY) = 3 read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0000\30\0\0\0\0\0\0"..., 832) = 832 fstat(3, {st_mode=S_IFREG|0755, st_size=24840, ...}) = 0 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29ca45000 mmap(NULL, 2120560, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fa29c414000 mprotect(0x7fa29c41a000, 2093056, PROT_NONE) = 0 mmap(0x7fa29c619000, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x5000) = 0x7fa29c619000 close(3) = 0 open("/lib64/libc.so.6", O_RDONLY) = 3 read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1\0\0\0\0\0"..., 832) = 832 fstat(3, {st_mode=S_IFREG|0755, st_size=1916528, ...}) = 0 mmap(NULL, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fa29c081000 mprotect(0x7fa29c20a000, 2097152, PROT_NONE) = 0 mmap(0x7fa29c40a000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x7fa29c40a000 mmap(0x7fa29c40f000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x7fa29c40f000 close(3) = 0 open("/lib64/libdl.so.2", O_RDONLY) = 3 read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\340\r\0\0\0\0\0\0"..., 832) = 832 fstat(3, {st_mode=S_IFREG|0755, st_size=19536, ...}) = 0 mmap(NULL, 2109696, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x7fa29be7d000 mprotect(0x7fa29be7f000, 2097152, PROT_NONE) = 0 mmap(0x7fa29c07f000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x2000) = 0x7fa29c07f000 close(3) = 0 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29ca44000 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29ca43000 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29ca42000 arch_prctl(ARCH_SET_FS, 0x7fa29ca43700) = 0 mprotect(0x7fa29c07f000, 4096, PROT_READ) = 0 mprotect(0x7fa29c40a000, 16384, PROT_READ) = 0 mprotect(0x7fa29ca4e000, 4096, PROT_READ) = 0 munmap(0x7fa29ca46000, 25665) = 0 uname({sys="Linux", node="lb1.local", ...}) = 0 umask(0177) = 022 brk(0) = 0x1c57000 brk(0x1c78000) = 0x1c78000 open("/etc/conntrackd/conntrackd.conf", O_RDONLY) = 3 ioctl(3, SNDCTL_TMR_TIMEBASE or TCGETS, 0x7fff09f67e50) = -1 ENOTTY (Inappropriate ioctl for device) fstat(3, {st_mode=S_IFREG|0644, st_size=13618, ...}) = 0 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29ca4c000 read(3, "#\n# Synchronizer settings\n#\nSync"..., 8192) = 8192 read(3, "# since the daemon may keep some"..., 8192) = 5426 read(3, "", 4096) = 0 open("/etc/nsswitch.conf", O_RDONLY) = 4 fstat(4, {st_mode=S_IFREG|0644, st_size=1688, ...}) = 0 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29ca4b000 read(4, "#\n# /etc/nsswitch.conf\n#\n# An ex"..., 4096) = 1688 read(4, "", 4096) = 0 close(4) = 0 munmap(0x7fa29ca4b000, 4096) = 0 open("/etc/ld.so.cache", O_RDONLY) = 4 fstat(4, {st_mode=S_IFREG|0644, st_size=25665, ...}) = 0 mmap(NULL, 25665, PROT_READ, MAP_PRIVATE, 4, 0) = 0x7fa29ca3b000 close(4) = 0 open("/lib64/libnss_files.so.2", O_RDONLY) = 4 read(4, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360!\0\0\0\0\0\0"..., 832) = 832 fstat(4, {st_mode=S_IFREG|0755, st_size=65928, ...}) = 0 mmap(NULL, 2151824, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 4, 0) = 0x7fa29bc6f000 mprotect(0x7fa29bc7b000, 2097152, PROT_NONE) = 0 mmap(0x7fa29be7b000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 4, 0xc000) = 0x7fa29be7b000 close(4) = 0 mprotect(0x7fa29be7b000, 4096, PROT_READ) = 0 munmap(0x7fa29ca3b000, 25665) = 0 open("/etc/protocols", O_RDONLY|O_CLOEXEC) = 4 fcntl(4, F_GETFD) = 0x1 (flags FD_CLOEXEC) fstat(4, {st_mode=S_IFREG|0644, st_size=6455, ...}) = 0 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29ca4b000 read(4, "# /etc/protocols:\n# $Id: protoco"..., 4096) = 4096 close(4) = 0 munmap(0x7fa29ca4b000, 4096) = 0 read(3, "", 8192) = 0 ioctl(3, SNDCTL_TMR_TIMEBASE or TCGETS, 0x7fff09f674d0) = -1 ENOTTY (Inappropriate ioctl for device) close(3) = 0 munmap(0x7fa29ca4c000, 4096) = 0 open("/var/log/conntrackd.log", O_RDWR|O_CREAT|O_APPEND, 0666) = 3 open("/var/lock/conntrack.lock", O_RDONLY|O_CREAT|O_EXCL|O_TRUNC, 0600) = 4 close(4) = 0 getpriority(PRIO_PROCESS, 0) = 20 setpriority(PRIO_PROCESS, 0, 4294967276) = 0 getpriority(PRIO_PROCESS, 0) = 40 mmap(NULL, 528384, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29c9c1000 mmap(NULL, 528384, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29c940000 open("/etc/localtime", O_RDONLY) = 4 fstat(4, {st_mode=S_IFREG|0644, st_size=2679, ...}) = 0 fstat(4, {st_mode=S_IFREG|0644, st_size=2679, ...}) = 0 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29ca4c000 read(4, "TZif2\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\n\0\0\0\n\0\0\0\0"..., 4096) = 2679 lseek(4, -1698, SEEK_CUR) = 981 read(4, "TZif2\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\v\0\0\0\v\0\0\0\0"..., 4096) = 1698 close(4) = 0 munmap(0x7fa29ca4c000, 4096) = 0 getpid() = 4564 fstat(3, {st_mode=S_IFREG|0600, st_size=86240, ...}) = 0 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7fa29ca4c000 write(3, "[Wed Nov 21 15:52:16 2012] (pid="..., 72) = 72 stat("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2679, ...}) = 0 write(3, "[Wed Nov 21 15:52:16 2012] (pid="..., 68) = 68 close(3) = 0 munmap(0x7fa29ca4c000, 4096) = 0 write(2, "ERROR: conntrackd cannot start, "..., 71ERROR: conntrackd cannot start, please check the logfile for more info ) = 71 unlink("/var/lock/conntrack.lock") = 0 exit_group(1) In /var/log/conntrackd.log: [Wed Nov 21 15:52:16 2012] (pid=4564) [ERROR] can't open channel socket [Wed Nov 21 15:52:16 2012] (pid=4564) [ERROR] initialization failed I haven't found anything interesting about "can't open channel socket". Can anyone help?