Failed to start Hadoop datanode. Return value: 1

启动某data节点失败：

service hadoop-hdfs-datanode start
starting datanode, logging to /var/log/hadoop-hdfs/xxxx.out
Failed to start Hadoop datanode. Return value: 1         [FAILED]

vim /var/log/hadoop-hdfs/xxxx.out

ulimit -a for user hdfs
core file size          (blocks, -c) 0
data seg size           (kbytes, -d) unlimited
scheduling priority             (-e) 0
file size               (blocks, -f) unlimited
pending signals                 (-i) 58780
max locked memory       (kbytes, -l) 64
max memory size         (kbytes, -m) unlimited
open files                      (-n) 65536
pipe size            (512 bytes, -p) 8
POSIX message queues     (bytes, -q) 819200
real-time priority              (-r) 0
stack size              (kbytes, -s) 10240
cpu time               (seconds, -t) unlimited
max user processes              (-u) 131072
virtual memory          (kbytes, -v) unlimited
file locks                      (-x) unlimited

ps -ef |grep java

kill -9 16140
重启：service hadoop-hdfs-datanode start

OK！
su hdfs
hdfs dfsadmin -report
可以看到dead的节点已经恢复过来。