I have ordered a new server Centos 4.3 with Cpanel WHM 10.8.0 cPanel 10.8.2-R119.

When I have transfered old server all accounts to this new server, some sites mysql database had a few problems. I found the new server is MySQL 4.1.xx and my old server is MySQL 4.0.xx. So I decide to downgrade MYSQL 4.1.X to MySQL 4.0.xx.

cPanel Tweak Settings only have MYSQL 4.1 or MYSQL 5.0 , so I vi /var/cpanel/cpanel.config,change mysql-version=4.1 into mysql-version=4.

then, you have to do the following:

cp -fr /var/lib/mysql /var/lib/mysql.old

rm -fr /var/lib/mysql

rm -f /usr/sbin/mysqld

/scripts/mysqlup --force

when installed mysql, I found a problem

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Attempting to restart mysql

Waiting for mysql to restart.... . . . . . . . . . . finished.

mysql status

/usr/bin/mysqladmin: connect to server at 'localhost' failed error: 'Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)' Check that mysqld is running and that the socket: '/var/lib/mysql/mysql.sock' exists! mysql has failed, please contact the sysadmin (result was "Warning, no valid mysql.sock file found.mysql has failed").

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when I was checking mysql logs, I found the problem was /etc/my.cnf. which needed to edit /etc/my.cnf with the edition of mysql 4.0.xx, such as

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[mysqld]

datadir=/var/lib/mysql

socket=/var/lib/mysql/mysql.sock

skip-locking

skip-bdb

skip-innodb

back_log = 200

query_cache_limit=1M

query_cache_type=1

query_cache_size = 16M

interactive_timeout=10

connect_timeout=2

max_connections=500

wait_timeout=10

long_query_time=5

thread_cache = 8

thread_concurrency = 4

key_buffer = 16M

max_allowed_packet = 1M

table_cache = 64

sort_buffer_size = 1M

net_buffer_length = 8K

myisam_sort_buffer_size = 64M

[mysql.server]

user=mysql

basedir=/var/lib

[safe_mysqld]

err-log=/var/log/mysqld.log

pid-file=/var/run/mysqld/mysqld.pid

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then, you have to do the following:

cp -fr /var/lib/mysql /var/lib/mysql.old

rm -fr /var/lib/mysql

rm -f /usr/sbin/mysqld

/scripts/mysqlup --force

If you install mysql finished, Cpanel downgrade MYSQL 4.1.X to MySQL 4.0.xx .