MySQL使用xtrabackup备份时报错’Too many open files’

报错信息

2019-04-25 14:04:48 7fd5e9b0a720  InnoDB: Operating system error number 24 in a file operation.
InnoDB: Error number 24 means 'Too many open files'.
InnoDB: Some operating system error numbers are described at
InnoDB: http://dev.mysql.com/doc/refman/5.6/en/operating-system-error-codes.html
InnoDB: Error: could not open single-table tablespace file ./user/user_group.ibd
InnoDB: We do not continue the crash recovery, because the table may become
InnoDB: corrupt if we cannot apply the log records in the InnoDB log to it.
InnoDB: To fix the problem and start mysqld:
InnoDB: 1) If there is a permission problem in the file and mysqld cannot
InnoDB: open the file, you should modify the permissions.
InnoDB: 2) If the table is not needed, or you can restore it from a backup,
InnoDB: then you can remove the .ibd file, and InnoDB will do a normal
InnoDB: crash recovery and ignore that table.
InnoDB: 3) If the file system or the disk is broken, and you cannot remove
InnoDB: the .ibd file, you can set innodb_force_recovery > 0 in my.cnf
InnoDB: and force InnoDB to continue crash recovery here.
innobackupex: got a fatal error with the following stacktrace: at /usr/bin/innobackupex line 2703
    main::wait_for_ibbackup_file_create('/share/db_backup/mysql_backup/201904251358/xtrabackup_suspend...') called at /usr/bin/innobackupex line 2723
    main::wait_for_ibbackup_suspend('/share/db_backup/mysql_backup/201904251358/xtrabackup_suspend...') called at /usr/bin/innobackupex line 1976
    main::backup() called at /usr/bin/innobackupex line 1601
innobackupex: Error: The xtrabackup child process has died at /usr/bin/innobackupex line 2703

ulimit -n 65535

修改my.cnf配置文件的参数

innodb_open_files = 10240
open-files-limit = 10240

vi /etc/selinux/config

将SELINUX=enforcing 改为 SELINUX=permissive