xtrabackup备份MySQL报错：InnoDB: Error number 24 means 'Too many open files'

xtrabackup备份MySQL报错：InnoDB: Error number 24 means 'Too many open files'

1.使用xtrabackup备份MySQL时出现如下报错：

 :: >> log scanned up to ()
xtrabackup: Generating a list of tablespaces
InnoDB: Allocated tablespace ID  for mysql/plugin, old maximum was
InnoDB: Operating system error number  in a file operation.
InnoDB: Error number  means 'Too many open files'
InnoDB: Some operating system error numbers are described at http://dev.mysql.com/doc/refman/5.7/en/operating-system-error-codes.html
InnoDB: File ./jira/AO_4B00E6_STASH_SETTINGS.ibd: 'open' returned OS error . Cannot continue operation
InnoDB: Cannot continue operation.

2.查看备份使用的user的ulimit

[root@linux mysql]# ulimit -a
core file size          (blocks, -c)
data seg size           (kbytes, -d) unlimited
scheduling priority             (-e)
file size               (blocks, -f) unlimited
pending signals                 (-i)
max locked memory       (kbytes, -l)
max memory size         (kbytes, -m) unlimited
open files                      (-n) 1024
pipe size            ( bytes, -p)
POSIX message queues     (bytes, -q)
real-time priority              (-r)
stack size              (kbytes, -s)
cpu time               (seconds, -t) unlimited
max user processes              (-u)
virtual memory          (kbytes, -v) unlimited
file locks                      (-x) unlimited

3.修改/etc/security/limits.conf

vim /etc/security/limits.conf

* soft nofile 

* hard nofile 

重新备份还是报错。

4.修改MySQL的配置文件，增加如下参数：

vim /etc/my.cnf

innodb_open_files=

重新备份成功！