[root@nixbox ~]# ping 192.168.0.5 connect: No buffer space available [root@nixbox ~]# ping 192.168.0.6 PING 192.168.0.6 (192.168.0.6) 56(84) bytes of data. 64 bytes from 192.168.0.6: icmp_seq=0 ttl=115 time=294 ms 64 bytes from 192.168.0.6: icmp_seq=1 ttl=115 time=299 ms --- 192.168.0.6 ping statistics --- 3 packets transmitted, 2 received, 33% packet loss, time 2003ms rtt min/avg/max/mdev = 294.385/297.013/299.642/2.684 ms, pipe 2 [root@nixbox ~]# ping 192.168.0.5 connect: No buffer space available [root@nixbox ~]# ping 192.168.0.6 PING 192.168.0.6 (192.168.0.6) 56(84) bytes of data. 64 bytes from 192.168.0.6: icmp_seq=0 ttl=115 time=294 ms --- 192.168.0.6 ping statistics --- 1 packets transmitted, 1 received, 0% packet loss, time 0ms rtt min/avg/max/mdev = 294.512/294.512/294.512/0.000 ms, pipe 2 [root@nixbox ~]# ping 192.168.0.5 connect: No buffer space available ==================Strace o/p================= execve("/bin/ping", ["ping", "192.168.0.5"], [/* 19 vars */]) = 0 uname({sys="Linux", node="host2.a4", ...}) = 0 brk(0) = 0x85ef000 access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory) open("/etc/ld.so.cache", O_RDONLY) = 3 fstat64(3, {st_mode=S_IFREG|0644, st_size=85547, ...}) = 0 old_mmap(NULL, 85547, PROT_READ, MAP_PRIVATE, 3, 0) = 0xb7efd000 close(3) = 0 open("/lib/libresolv.so.2", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\3603\253"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0755, st_size=79488, ...}) = 0 old_mmap(NULL, 75944, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x97a000 old_mmap(0x989000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0xf000) = 0x989000 old_mmap(0x98b000, 6312, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x98b000 close(3) = 0 open("/lib/tls/libc.so.6", O_RDONLY) = 3 read(3, "\177ELF\1\1\1\0\0\0\0\0\0\0\0\0\3\0\3\0\1\0\0\0\20/\203"..., 512) = 512 fstat64(3, {st_mode=S_IFREG|0755, st_size=1454546, ...}) = 0 old_mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7efc000 old_mmap(NULL, 1219772, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0xc4f000 old_mmap(0xd73000, 16384, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x124000) = 0xd73000 old_mmap(0xd77000, 7356, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0xd77000 close(3) = 0 old_mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0xb7efb000 mprotect(0xd73000, 4096, PROT_READ) = 0 mprotect(0x2d5000, 4096, PROT_READ) = 0 set_thread_area({entry_number:-1 -> 6, base_addr:0xb7efb6c0, limit:1048575, seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, seg_not_present:0, useable:1}) = 0 munmap(0xb7efd000, 85547) = 0 socket(PF_INET, SOCK_RAW, IPPROTO_ICMP) = 3 getuid32() = 0 setuid32(0) = 0 socket(PF_INET, SOCK_DGRAM, IPPROTO_IP) = 4 connect(4, {sa_family=AF_INET, sin_port=htons(1025), sin_addr=inet_addr("192.168.0.5")}, 16) = -1 ENOBUFS (No buffer space available) dup(2) = 5 fcntl64(5, F_GETFL) = 0x8001 (flags O_WRONLY|O_LARGEFILE) close(5) = 0 write(2, "connect: No buffer space availab"..., 35connect: No buffer space available ) = 35 exit_group(2) = ? Process 31135 detached