基本上这和您已经做过的从 lenny 升级没有什么区别。唯一的区别就是，您首先需要确定您的软件包列表仍旧引用像在 第 A.2 节 “检查您的 sources list” 说明的 lenny 中的软件包。

如果您从 Debian 镜像升级，将自动升级到最新的 lenny 。

If any of the lines in your /etc/apt/sources.list refer to 'stable', you are effectively already “using” squeeze. This might not be what you want if you are not ready yet for the upgrade. If you have already run apt-get update, you can still get back without problems following the procedure below.

如果您已经从 squeeze 安装了软件包，就没有太大的必要从 lenny 安装软件包了。在这种情况下，您必须决定是否继续或者终止。可以降级软件包，但是这里不会提及。

用您喜欢的编辑器(以 root 权限)打开文件 /etc/apt/sources.list，检查所有以 deb http: 或 deb ftp: 开头，引用 “stable” 的行。如果找到了，将 stable 改为 lenny 。

如果有些行以 deb file: 开始，您应该自己检查该位置是否包含有 lenny 或者 squeeze 的档案。

	重要
	不要修改任何以 deb cdrom: 开始的行。如果这样做了的话，这些行就会失效，您将需要重新运行 apt-cdrom 。即使在 'cdrom' 的行发现 “unstable”，也不要感到奇怪。虽然令人困惑，但这是正常的。

如果做了任何修改，保存文件后执行

# apt-get update

刷新软件包列表。

If your system is localised and is using a locale that is not based on UTF-8 you should strongly consider switching your system over to using UTF-8 locales. In the past, there have been bugs identified that manifest itself only when using a non-UTF-8 locale. On the desktop, such legacy locales are supported through ugly hacks in the libraries internals, and we cannot decently provide support for users who still use them.

To configure your system's locale you can run dpkg-reconfigure locales. Ensure you select an UTF-8 locale when you are presented with the question asking which locale to use as a default in the system. In addition, you should review the locale settings of your users and ensure that they do not have legacy locales definitions in their configuration environment.