使用Rails启动WEBrick服务器时出错

Question

我有一个已经准备好数据库的现有应用程序，我已经在database.yml中进行了所有更改，并在尝试使用Rails启动WEBrick服务器时进行了捆绑安装，但出现以下错误

/usr/lib/ruby/1.9.1/fileutils.rb:247:in `mkdir': File exists - /home/username/appname/app/releases/20120831125545/tmp (Errno::EEXIST)
from /usr/lib/ruby/1.9.1/fileutils.rb:247:in `fu_mkdir'
from /usr/lib/ruby/1.9.1/fileutils.rb:221:in `block (2 levels) in mkdir_p'
from /usr/lib/ruby/1.9.1/fileutils.rb:219:in `reverse_each'
from /usr/lib/ruby/1.9.1/fileutils.rb:219:in `block in mkdir_p'
from /usr/lib/ruby/1.9.1/fileutils.rb:205:in `each'
from /usr/lib/ruby/1.9.1/fileutils.rb:205:in `mkdir_p'
from /home/username/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.0.10/lib/rails/commands/server.rb:62:in `block in start'
from /home/username/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.0.10/lib/rails/commands/server.rb:61:in `each'
from /home/username/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.0.10/lib/rails/commands/server.rb:61:in `start'
from /home/username/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.0.10/lib/rails/commands.rb:30:in `block in <top (required)>'
from /home/username/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.0.10/lib/rails/commands.rb:27:in `tap'
from /home/username/.rvm/gems/ruby-1.9.3-p194/gems/railties-3.0.10/lib/rails/commands.rb:27:in `<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'

我是否缺少某些步骤，是否需要重新运行迁移（数据库已经准备好，其中包含数据）有什么帮助吗？

Answer 1

显然，Rails用于会话存储的tmp目录已经存在。 尝试删除发行目录中的/ tmp文件夹。