MySQL starts the error in Mysqld_safe Safe mode

The mysqld_safe that uses the binary compilation file starts the error as follows:

[MYSQL@ECP-UC-DB1 ~]$ Mysqld_safe
110707 21:31:19 mysqld_safe Logging to '/opt/mysql/mysqldata/ecp-uc-db1.err '.
110707 21:31:19 Mysqld_safe the File/usr/local/mysql/bin/mysqld
Does not exist or are not executable. Please CD to the MySQL installation
Directory and restart this script from there as follows:
./bin/mysqld_safe&
Http://dev.mysql.com/doc/mysql/en/mysqld-safe.html for more information

Workaround:

Su–root
Mkdir/usr/local/mysql/bin
Ln-s/opt/mysql/product/5.5/bin/mysqld/usr/local/mysql/bin/mysqld

Execute Mysqld_safe again

[MYSQL@ECP-UC-DB1 ~]$ Mysqld_safe
110707 21:32:37 mysqld_safe Logging to '/opt/mysql/mysqldata/ecp-uc-db1.err '.
110707 21:32:37 Mysqld_safe starting mysqld daemon with databases From/opt/mysql/mysqldata

Startup results:

MySQL 26885 23452 0 21:32 pts/0 00:00:00/bin/sh/opt/mysql/product/5.5/bin/mysqld_safe
MySQL 27653 26885 0 21:32 pts/0 00:00:00/usr/local/mysql/bin/mysqld–basedir=/opt/mysql/product/5.5–datadir=/opt/ mysql/mysqldata–plugin-dir=/usr/local/mysql/lib/plugin–log-error=/opt/mysql/mysqldata/ecp-uc-db1.err– open-files-limit=8192–pid-file=/var/run/mysqld/mysqld.pid–socket=/var/run/mysqld/mysqld.sock–port=3306

Problem exists reason:

1, Mysqld_safe only know/usr/local/mysql/bin/mysqld (perhaps the configuration problem)
2, MY.CNF can only be placed under/etc/, otherwise use –defaults-file can not read my.cnf file (there are doubts)

Summing up, different problems may be a little different, we need to according to their own experience to analyze the reasons oh.