mysqld_safe error: log-error set to however file don’t exists on compiled mysql8.0

2018-08-20 KENNETH 0

환경 OS : CentOS7 DB : mysql-8.0.11, mysql-8.0.12 (8.0.11 이전에도 문제가 있었는지는 모르지만 아마 있을듯)   문제점 mysql  실행시 아래와 같은 메세지와 함께 실행 불가 # mysql.server start Starting MySQL.2018-08-20T04:33:38.742995Z mysqld_safe error: log-error set to ‘/var/log/mysql/mysql_error.log’, however file don’t exists. Create writable for user ‘mysql’. The server quit without updating PID file (/var/lib/mysql/myserver.pid).   원인 보통의 원인이라면 로그가 쌓여야 하는 위치(예제 : /var/log/mysql)가 존재하지 않을 경우 로그가 쌓여야 하는 위치의 권한이 mysql 유저가 “쓰기(write)” 가능하지 않을 경우   여야 하지만.. 현재 시스템의 상황은 이런 문제가 있지 않음… my.cnf 설정중 log_error 옵션을 손대지 않고 그대로 실행했을 경우는 문제가 없지만 log_error=/var/log/mysql/mysql_error.log 등으로 기본값이 아닌 “수정”이 이루어졌을 경우에 발생 하고 있음   해결 touch /var/log/mysql/mysql_error.log chown mysql.mysql /var/log/mysql/mysql_error.log 이렇게 생성 & 권한부여 를 해주면 정상 구동이 됨… 듣는 사람은 당연히 황당 하겠지만… 지금 이 결과가 mysql-8.0.11, mysql-8.0.12 를 소스컴파일 설치 했을 때 발생 [ more… ]

Difference between MySQL Connector/J 5.1 and MySQL Connector/J 8.0

2018-08-01 KENNETH 0

Difference between MySQL Connector/J 5.1 and MySQL Connector/J 8.0   Summary of Connector/J Versions Connector/J version JDBC version MySQL Server version JRE Supported JDK Required for Compilation Status 8.0 4.2 5.5, 5.6, 5.7, 8.0 1.8.x 1.8.x General availability. Recommended version. 5.1 3.0, 4.0, 4.1, 4.2 5.5, 5.6*, 5.7*, 8.0* 1.5.x, 1.6.x, 1.7.x, 1.8.x* 1.5.x and 1.8.x General availability   Difference ClassName MySQL Connector/J 5.1 package name : java.sql (java.sql.*) class name : com.mysql.jdbc.Driver MySQL Connector/J 8.0 package name : java.sql (java.sql.*) class name : com.mysql.cj.jdbc.Driver    

Host ‘::1’ is not allowed to connect on mysql8 with telnet

2018-08-01 KENNETH 0

발단 확인을 위해 무심코 실행한 명령어…. # telnet localhost 3306 # telnet 127.0.0.1 3306 (위에것이 안되서 혹시나 하고)     에러메세지 # telnet localhost 3306 Trying ::1… Connected to localhost. Escape character is ‘^]’. <Host ‘::1’ is not allowed to connect to this MySQL serverConnection closed by foreign host.     사용환경 OS : CentOS7 MySQL : 8.0 원래 mariadb, mysql-5.7 등등등을 계속 변경 하면서 돌리다가 최근 업데이트 함 mysql -uroot -p dbname 또는 mysql -hlocalhost -uroot -p dbname 등으로 정상 접근 되고… 실제로 동일한 서버내에 WEB+DB가 같이 작동하며… dbhost = localhost port = 3306 형태의 설정으로 문제없이 사용중인데… ㄷ ㄷ ㄷ ㄷ     원인 세상에.. 이게 원인이.. 대체… skip_name_resolve 때문 이라니!!!!!! 참고로 mariadb-10.2, mysql-5.7 까지는 저 옵션이 활성화 된 상황에서도 telnet localhost 3306 명령에 이슈가 발생하지는 않았었다.     해결 skip_name_resolve 옵션을 해제….     고찰 “지금 이 [ more… ]

MySQL 8.0 Keywords and Reserved Words

2018-07-04 KENNETH 0

URL : https://dev.mysql.com/doc/refman/8.0/en/keywords.html   MySQL 8.0 Keywords and Reserved Words The following list shows the keywords and reserved words in MySQL 8.0, along with changes to individual words from version to version. Reserved keywords are marked with (R). In addition, _FILENAME is reserved. At some point, you might upgrade to a higher version, so it is a good idea to have a look at future reserved words, too. You can find these in the manuals that cover higher versions of MySQL. Most of the reserved words in the list are forbidden by standard SQL as column or table names (for example, GROUP). A few are reserved because MySQL needs them and uses a yacc parser.   A ACCESSIBLE (R) ACCOUNT ACTION ADD (R) ADMIN became nonreserved in 8.0.12 AFTER AGAINST AGGREGATE ALGORITHM ALL (R) ALTER (R) ALWAYS ANALYSE removed in 8.0.1 [ more… ]

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mysql server system variables log_warnings to log_error_verbosity

2016-10-04 KENNETH 0

url : http://dev.mysql.com/doc/refman/5.7/en/server-system-variables.html   under 5.7.2 : log_warnings over 5.7.2 : log_error_verbosity   log_warnings Deprecated 5.7.2 Command-Line Format –log-warnings[=#] System Variable Name log_warnings Variable Scope Global Dynamic Variable Yes Permitted Values (32-bit platforms, <= 5.7.1) Type integer Default 1 Min Value 0 Max Value 4294967295 Permitted Values (32-bit platforms, >= 5.7.2) Type integer Default 2 Min Value 0 Max Value 4294967295 Permitted Values (64-bit platforms, <= 5.7.1) Type integer Default 1 Min Value 0 Max Value 18446744073709551615 Permitted Values (64-bit platforms, >= 5.7.2) Type integer Default 2 Min Value 0 Max Value 18446744073709551615 Whether to produce additional warning messages to the error log. This variable is enabled by default (the default is 1 before MySQL 5.7.2, 2 as of 5.7.2). To disable it, set it to 0. The server logs messages about statements that are unsafe for statement-based logging if the [ more… ]