Your current output shows all locale variables set to zh_CN.GBK encoding. This legacy Chinese encoding can cause problems with:
- Modern web applications
- Database systems expecting UTF-8
- File processing scripts
- Internationalization tools


First verify available UTF-8 locales on your system:

# locale -a | grep zh_CN.utf8
zh_CN.utf8
zh_CN.UTF-8
If missing, generate them:
# localedef -i zh_CN -f UTF-8 zh_CN.UTF-8
For testing purposes, you can temporarily switch to UTF-8:
# export LANG=zh_CN.UTF-8
# export LC_ALL=zh_CN.UTF-8
Verify with:
# locale | grep -E 'LANG|LC_'
For CentOS 5.5, edit these files:
1. System-wide default (affects new users):
# vi /etc/sysconfig/i18n
LANG="zh_CN.UTF-8"
LC_ALL="zh_CN.UTF-8"
2. User-specific override (in ~/.bashrc):
export LANG=zh_CN.UTF-8
export LC_ALL=zh_CN.UTF-8
After changes, verify with:
# locale
# locale -k LC_CTYPE | grep charmap
Common issues:

- Missing locale packages: yum groupinstall "Chinese Support"

- SSH session caching: Start new session after changes

- Service restart requirements: Some daemons need restart
Some applications may require additional configuration:
For Apache:
AddDefaultCharset UTF-8
For MySQL:
[client]
default-character-set=utf8

[mysqld]
character-set-server=utf8
collation-server=utf8_general_ci
For PHP:
default_charset = "UTF-8"
mbstring.internal_encoding=UTF-8
mbstring.http_output=UTF-8


When working with internationalization on CentOS 5.5, you might encounter Chinese character encoding issues if your system uses GBK encoding instead of UTF-8. Here's a typical locale output showing GBK configuration:
LANG=zh_CN.GBK
LC_CTYPE="zh_CN.GBK"
LC_NUMERIC="zh_CN.GBK"
LC_TIME="zh_CN.GBK"
LC_COLLATE="zh_CN.GBK"
LC_MONETARY="zh_CN.GBK"
LC_MESSAGES="zh_CN.GBK"
LC_PAPER="zh_CN.GBK"
LC_NAME="zh_CN.GBK"
LC_ADDRESS="zh_CN.GBK"
LC_TELEPHONE="zh_CN.GBK"
LC_MEASUREMENT="zh_CN.GBK"
LC_IDENTIFICATION="zh_CN.GBK"
LC_ALL=

First, verify available UTF-8 locales and generate if necessary:
# Check available locales
locale -a | grep zh_CN

# Generate UTF-8 locale if not present
sudo localedef -v -c -i zh_CN -f UTF-8 zh_CN.UTF-8

Edit the system locale configuration file:
sudo vi /etc/sysconfig/i18n

Modify the content to:
LANG="zh_CN.UTF-8"
SUPPORTED="zh_CN.UTF-8:zh_CN:zh"
SYSFONT="latarcyrheb-sun16"

For immediate effect in current session (without reboot):
source /etc/sysconfig/i18n

To verify the changes:
locale

For individual users who need UTF-8 without changing system defaults:
echo 'export LANG=zh_CN.UTF-8' >> ~/.bashrc
echo 'export LC_ALL=zh_CN.UTF-8' >> ~/.bashrc
source ~/.bashrc

If you encounter issues after changing locale settings:

Check if the UTF-8 locale is properly generated with locale -a
Verify file permissions on /etc/sysconfig/i18n
Restart terminal sessions or SSH connections
For applications requiring specific encoding, set LC_CTYPE individually

When changing system locale in CentOS 5.5:

Some legacy applications might have compatibility issues with UTF-8
Existing files with GBK encoding won't automatically convert
System logs and cron jobs may be affected by locale changes
Consider testing changes in a development environment first