DebugAH

Problem description: Some errors occur when running the xtrabackup backup script on the database

DB_version:mysql8.0.26

Xtrabackup: percona-xtrabackup-8.0.27-19-Linux-x86_64.glibc2.12.tar.gz

[root@orch2 scripts]# $xtrDir --defaults-file=$mysql_cnf --user=$mysql_user --password=$mysql_password --socket=$mysql_socket --compress --compress-threads= 2 --backup -- target-dir= $target_dir
xtrabackup: recognized server arguments: --datadir=/home/mysql/db_orch2/data --tmpdir=/home/mysql/db_orch2/tmp --log_bin=/home/mysql/db_orch2/binlog/orch2-bin --log- bin-index=/home/mysql/db_orch2/binlog/orch2-bin.index --server-id= 1330611 --innodb_open_files= 63000 --innodb_data_home_dir=/home/mysql/db_orch2/data --innodb_log_group_home_dir=/home/mysql /db_orch2/data --innodb_log_file_size=8G --innodb_log_files_in_group= 4 --innodb_undo_directory=/home/mysql/db_orch2/ulog --innodb_undo_tablespaces= 3 --innodb_flush_log_at_trx_commit= 2 --innodb_flush_method=O_DIRECT --innodb_io_capacity= 3000--innodb_buffer_pool_size=64G --innodb_log_buffer_size=32M --innodb_max_dirty_pages_pct= 85 --innodb_adaptive_hash_index= 1 --innodb_data_file_path=ibdata1:512M:autoextend --innodb_write_io_threads= 16 --innodb_read_io_threads = 16  
xtrabackup: recognized client arguments --password=* --socket=/home/mysql/db_orch2/mysql.sock --compress --compress-threads= 2 --backup= 1 --target-dir=/home/mysql/backup/ 13306 // 2022-04-06 
/root/percona-xtrabackup/bin/xtrabackup version 8.0 . 27 - 19 based on MySQL server 8.0 .27 Linux (x86_64) (revision id: 50dbc8dadda)
Can ' t locate Data/Dumper.pm in @INC (@INC contains: /usr/local/lib64/perl5 /usr/local/share/perl5 /usr/lib64/perl5/vendor_perl /usr/share/perl5/vendor_perl / usr/lib64/perl5 /usr/share/perl5 .) at - line 749. 
BEGIN failed--compilation aborted at - line 749 .
 220406  12 : 26 : 14 Connecting to MySQL server host: localhost, user: root, password: set , port: not set , socket : /home/mysql/db_orch2/mysql.sock
Using server version 8.0 . 26 
220406  12 : 26 : 14 Executing LOCK INSTANCE FOR BACKUP...
xtrabackup: uses posix_fadvise().
xtrabackup: cd to /home/mysql/db_orch2/ data
xtrabackup: open files limit requested 0 , set to 1024 
xtrabackup: using the following InnoDB configuration:
xtrabackup: innodb_data_home_dir = /home/mysql/db_orch2/ data
xtrabackup: innodb_data_file_path = ibdata1:512M:autoextend
xtrabackup: innodb_log_group_home_dir = /home/mysql/db_orch2/ data
xtrabackup: innodb_log_files_in_group = 4 
xtrabackup: innodb_log_file_size = 8589934592 
xtrabackup: using O_DIRECT
Number of pools: 1
xtrabackup: initialize_service_handles suceeded
220406  12 : 26 : 14 Connecting to MySQL server host: localhost, user: root, password: set , port: not set , socket: /home/mysql/db_orch2/mysql.sock
xtrabackup: Redo Log Archiving is not set up.
Starting to parse redo log at lsn = 1276785485862 
220406  12 : 26 : 14 >> log scanned up to ( 1276786464962 )
xtrabackup: Generating a list of tablespaces
xtrabackup: Generating a list of tablespaces
Scanning ' ./ ' 
Scanning ' /home/mysql/db_orch2/ulog/ ' 
Completed space ID check of 2 files.
Allocated tablespace ID 2198  for eomaqzy_data/app_source_rela, old maximum was 0 
220406  12 : 26 : 15 >> log scanned up to ( 1276786574060 )
Undo tablespace number 1 was being truncated when mysqld quit.
Cannot recover a truncated undo tablespace in read- only mode
 xtrabackup: error: xb_load_tablespaces() failed with error code 57

 

Check whether there are undo files in the data file directory, clean up the undo files and test the backup again

 

mv undo*.log /tmp

 

 

 

 

 

Error two:

 

 

xtrabackup: Can ' t create/write to file ' /home/mysql/backup/ 13306 / 2022-04-06 /eomaqzy_data/pl02_inv_meter_data.ibd.qp ' ( OS errno 24 - Too many open files) You 
are in / var /spool There are mails in /mail/root

 

 

OS file count unadjusted limit

[root@orch2 13306 ]# ulimit - n
 1024

[root@orch2 ~]# grep -i nofile /etc/security/limits.conf
#         - nofile - max number of open file descriptors

[root@orch2 ~]# vim /etc/security/limits.conf
 * hard nofile 65535 
* soft nofile 65535

Disconnect and log back in
[root@orch2 ~]# ulimit - n
 65535

 

back up again

+ echo =========================Run full backup beginning =================== =======
+ /root/percona-xtrabackup/bin/xtrabackup --defaults-file=/home/mysql/db_orch2/conf/orch2.cnf --user=root --password=XXXXX --socket=/home/mysql/db_orch2/ mysql.sock --compress --compress-threads= 2 --backup --target - dir=/home/mysql/backup/ 13306 / 2022-04-06 + 
echo =========== ============Run full backup 
finished successfully ======================================================================================================================================== There are mails in /mail/root