我已经调试了一天多，没有运气，
安装 ruby、gems 和Passenger 后，我尝试启动Passenger，但不断收到“找不到乘客”：
passenger@dragon:/usr/website/myapp/current$ passenger start -p 4000 -e production -d
/home/passenger/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/dependency.rb:247:in `to_specs': Could not find passenger (>= 0) amongst [actionmailer-3.2.8, actionmailer-3.2.3, actionpack-3.2.8, actionpack-3.2.3, activemodel-3.2.8, activemodel-3.2.3, activerecord-3.2.8, activerecord-3.2.3, activeresource-3.2.8, activeresource-3.2.3, activesupport-3.2.8, activesupport-3.2.3, arel-3.0.2, bcrypt-ruby-3.0.1, builder-3.0.3, builder-3.0.0, cape-1.4.0, capistrano-2.13.4, coffee-rails-3.2.2, coffee-script-2.2.0, coffee-script-source-1.3.3, devise-2.1.2, devise_ldap_authenticatable-0.6.1, erubis-2.7.0, execjs-1.4.0, guess_html_encoding-0.0.4, high_voltage-1.1.1, highline-1.6.15, hike-1.2.1, i18n-0.6.1, i18n-0.6.0, journey-1.0.4, jquery-rails-2.0.2, jruby-pageant-1.1.1, jsmin-1.0.1, json-1.7.3, libv8-3.3.10.4-x86-linux, mail-2.4.4, mime-types-1.19, mini_magick-3.4, multi_json-1.3.6, net-ldap-0.2.2, net-scp-1.0.4, net-sftp-2.0.5, net-ssh-2.6.0, net-ssh-gateway-1.1.0, nokogiri-1.5.5, orm_adapter-0.4.0, polyglot-0.3.3, rack-1.4.1, rack-cache-1.2, rack-ssl-1.3.2, rack-test-0.6.1, rails-3.2.8, rails-3.2.3, rails-settings-cached-0.2.1, railties-3.2.8, railties-3.2.3, rake-0.9.2.2, rdoc-3.12, ruby-readability-0.5.4, rvm-capistrano-1.2.7, sass-3.1.20, sass-rails-3.2.5, sprockets-2.1.3, sqlite3-1.3.6, subexec-0.2.2, swfobject-rails-1.1.1, therubyracer-0.10.1, thor-0.16.0, thor-0.14.6, tilt-1.3.3, treetop-1.4.10, tzinfo-0.3.33, uglifier-1.2.5, warden-1.2.1] (Gem::LoadError)
from /home/passenger/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems/dependency.rb:256:in `to_spec'
from /home/passenger/.rvm/rubies/ruby-1.9.3-p194/lib/ruby/site_ruby/1.9.1/rubygems.rb:1231:in `gem'
from /home/passenger/.rvm/gems/ruby-1.9.3-p194/bin/passenger:18:in `<main>'
from /home/passenger/.rvm/gems/ruby-1.9.3-p194/bin/ruby_noexec_wrapper:14:in `eval'
from /home/passenger/.rvm/gems/ruby-1.9.3-p194/bin/ruby_noexec_wrapper:14:in `<main>'
gem install passenger如您所见，在安装了Passenger gem（我曾经安装过它）时：
passenger@dragon:/usr/website/myapp/current$ gem list
*** LOCAL GEMS ***
actionmailer (3.2.3)
actionpack (3.2.3)
activemodel (3.2.3)
activerecord (3.2.3)
activeresource (3.2.3)
activesupport (3.2.3)
arel (3.0.2)
bcrypt-ruby (3.0.1)
builder (3.0.0)
bundler (1.2.1)
cape (1.4.0)
capistrano (2.13.4)
coffee-rails (3.2.2)
coffee-script (2.2.0)
coffee-script-source (1.3.3)
daemon_controller (1.0.0)
devise (2.1.2)
devise_ldap_authenticatable (0.6.1)
erubis (2.7.0)
execjs (1.4.0)
fastthread (1.0.7)
file-tail (1.0.11)
guess_html_encoding (0.0.4)
high_voltage (1.1.1)
highline (1.6.15)
hike (1.2.1)
i18n (0.6.0)
journey (1.0.4)
jquery-rails (2.0.2)
jruby-pageant (1.1.1)
jsmin (1.0.1)
json (1.7.3)
libv8 (3.3.10.4 x86-linux)
mail (2.4.4)
mime-types (1.19)
mini_magick (3.4)
multi_json (1.3.6)
net-ldap (0.2.2)
net-scp (1.0.4)
net-sftp (2.0.5)
net-ssh (2.6.0)
net-ssh-gateway (1.1.0)
nokogiri (1.5.5)
orm_adapter (0.4.0)
passenger (3.0.17)
polyglot (0.3.3)
rack (1.4.1)
rack-cache (1.2)
rack-ssl (1.3.2)
rack-test (0.6.1)
rails (3.2.3)
rails-settings-cached (0.2.1)
railties (3.2.3)
rake (0.9.2.2)
rdoc (3.12)
ruby-readability (0.5.4)
rubygems-bundler (1.1.0)
rvm (1.11.3.5)
rvm-capistrano (1.2.7)
sass (3.1.20)
sass-rails (3.2.5)
sprockets (2.1.3)
sqlite3 (1.3.6)
subexec (0.2.2)
swfobject-rails (1.1.1)
therubyracer (0.10.1)
thor (0.14.6)
tilt (1.3.3)
tins (0.5.5)
treetop (1.4.10)
tzinfo (0.3.33)
uglifier (1.2.5)
warden (1.2.1)
这是我的宝石环境：
passenger@dragon:/usr/website/myapp/current$ gem env
RubyGems Environment:
- RUBYGEMS VERSION: 1.8.24
- RUBY VERSION: 1.9.3 (2012-04-20 patchlevel 194) [i686-linux]
- INSTALLATION DIRECTORY: /home/passenger/.rvm/gems/ruby-1.9.3-p194
- RUBY EXECUTABLE: /home/passenger/.rvm/rubies/ruby-1.9.3-p194/bin/ruby
- EXECUTABLE DIRECTORY: /home/passenger/.rvm/gems/ruby-1.9.3-p194/bin
- RUBYGEMS PLATFORMS:
- ruby
- x86-linux
- GEM PATHS:
- /home/passenger/.rvm/gems/ruby-1.9.3-p194
- /home/passenger/.rvm/gems/ruby-1.9.3-p194@global
- GEM CONFIGURATION:
- :update_sources => true
- :verbose => true
- :benchmark => false
- :backtrace => false
- :bulk_threshold => 1000
- REMOTE SOURCES:
- http://rubygems.org/
这是 rvm 信息：
passenger@dragon:/usr/website/myapp/current$ rvm info
ruby-1.9.3-p194:
system:
uname: "Linux dragon 3.2.0-26-generic-pae #41-Ubuntu SMP Thu Jun 14 16:45:14 UTC 2012 i686 i686 i386 GNU/Linux"
bash: "/bin/bash => GNU bash, version 4.2.24(1)-release (i686-pc-linux-gnu)"
zsh: " => not installed"
rvm:
version: "rvm 1.15.9 (stable) by Wayne E. Seguin <wayneeseguin@gmail.com>, Michal Papis <mpapis@gmail.com> [https://rvm.io/]"
updated: "2 days 23 hours 20 minutes 14 seconds ago"
ruby:
interpreter: "ruby"
version: "1.9.3p194"
date: "2012-04-20"
platform: "i686-linux"
patchlevel: "2012-04-20 revision 35410"
full_version: "ruby 1.9.3p194 (2012-04-20 revision 35410) [i686-linux]"
homes:
gem: "/home/passenger/.rvm/gems/ruby-1.9.3-p194"
ruby: "/home/passenger/.rvm/rubies/ruby-1.9.3-p194"
binaries:
ruby: "/home/passenger/.rvm/rubies/ruby-1.9.3-p194/bin/ruby"
irb: "/home/passenger/.rvm/rubies/ruby-1.9.3-p194/bin/irb"
gem: "/home/passenger/.rvm/rubies/ruby-1.9.3-p194/bin/gem"
rake: "/home/passenger/.rvm/gems/ruby-1.9.3-p194@global/bin/rake"
environment:
PATH: "/home/passenger/.rvm/gems/ruby-1.9.3-p194/bin:/home/passenger/.rvm/gems/ruby-1.9.3-p194@global/bin:/home/passenger/.rvm/rubies/ruby-1.9.3-p194/bin:/home/passenger/.rvm/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games"
GEM_HOME: "/home/passenger/.rvm/gems/ruby-1.9.3-p194"
GEM_PATH: "/home/passenger/.rvm/gems/ruby-1.9.3-p194:/home/passenger/.rvm/gems/ruby-1.9.3-p194@global"
MY_RUBY_HOME: "/home/passenger/.rvm/rubies/ruby-1.9.3-p194"
IRBRC: "/home/passenger/.rvm/rubies/ruby-1.9.3-p194/.irbrc"
RUBYOPT: ""
gemset: ""
这是引发错误的方法（第 247 行）：
1 require "rubygems/requirement"
2
3 ##
4 # The Dependency class holds a Gem name and a Gem::Requirement.
5
6 class Gem::Dependency
7
8 ##
9 # Valid dependency types.
10 #--
11 # When this list is updated, be sure to change
12 # Gem::Specification::CURRENT_SPECIFICATION_VERSION as well.
13
14 TYPES = [
15 :development,
16 :runtime,
17 ]
18
19 ##
20 # Dependency name or regular expression.
21
22 attr_accessor :name
23
24 ##
25 # Allows you to force this dependency to be a prerelease.
26
27 attr_writer :prerelease
28
29 ##
30 # Constructs a dependency with +name+ and +requirements+. The last
31 # argument can optionally be the dependency type, which defaults to
32 # <tt>:runtime</tt>.
33
34 def initialize name, *requirements
35 if Regexp === name then
36 msg = ["NOTE: Dependency.new w/ a regexp is deprecated.",
37 "Dependency.new called from #{Gem.location_of_caller.join(":")}"]
38 warn msg.join("\n") unless Gem::Deprecate.skip
39 end
40
41 type = Symbol === requirements.last ? requirements.pop : :runtime
42 requirements = requirements.first if 1 == requirements.length # unpack
43
44 unless TYPES.include? type
45 raise ArgumentError, "Valid types are #{TYPES.inspect}, "
46 + "not #{type.inspect}"
47 end
48
49 @name = name
50 @requirement = Gem::Requirement.create requirements
51 @type = type
52 @prerelease = false
53
54 # This is for Marshal backwards compatibility. See the comments in
55 # +requirement+ for the dirty details.
56
57 @version_requirements = @requirement
58 end
59
60 ##
61 # A dependency's hash is the XOR of the hashes of +name+, +type+,
62 # and +requirement+.
63
64 def hash # :nodoc:
65 name.hash ^ type.hash ^ requirement.hash
66 end
67
68 def inspect # :nodoc:
69 "<%s type=%p name=%p requirements=%p>" %
70 [self.class, self.type, self.name, requirement.to_s]
71 end
72
73 ##
74 # Does this dependency require a prerelease?
75
76 def prerelease?
77 @prerelease || requirement.prerelease?
78 end
79
80 def pretty_print q # :nodoc:
81 q.group 1, 'Gem::Dependency.new(', ')' do
82 q.pp name
83 q.text ','
84 q.breakable
85
86 q.pp requirement
87
88 q.text ','
89 q.breakable
90
91 q.pp type
92 end
93 end
94
95 ##
96 # What does this dependency require?
97
98 def requirement
99 return @requirement if defined?(@requirement) and @requirement
100
101 # @version_requirements and @version_requirement are legacy ivar
102 # names, and supported here because older gems need to keep
103 # working and Dependency doesn't implement marshal_dump and
104 # marshal_load. In a happier world, this would be an
105 # attr_accessor. The horrifying instance_variable_get you see
106 # below is also the legacy of some old restructurings.
107 #
108 # Note also that because of backwards compatibility (loading new
109 # gems in an old RubyGems installation), we can't add explicit
110 # marshaling to this class until we want to make a big
111 # break. Maybe 2.0.
112 #
113 # Children, define explicit marshal and unmarshal behavior for
114 # public classes. Marshal formats are part of your public API.
115
116 if defined?(@version_requirement) && @version_requirement
117 version = @version_requirement.instance_variable_get :@version
118 @version_requirement = nil
119 @version_requirements = Gem::Requirement.new version
120 end
121
122 @requirement = @version_requirements if defined?(@version_requirements)
123 end
124
125 def requirements_list
126 requirement.as_list
127 end
128
129 def to_s # :nodoc:
130 if type != :runtime then
131 "#{name} (#{requirement}, #{type})"
132 else
133 "#{name} (#{requirement})"
134 end
135 end
136
137 ##
138 # Dependency type.
139
140 def type
141 @type ||= :runtime
142 end
143
144 def == other # :nodoc:
145 Gem::Dependency === other &&
146 self.name == other.name &&
147 self.type == other.type &&
148 self.requirement == other.requirement
149 end
150
151 ##
152 # Dependencies are ordered by name.
153
154 def <=> other
155 self.name <=> other.name
156 end
157
158 ##
159 # Uses this dependency as a pattern to compare to +other+. This
160 # dependency will match if the name matches the other's name, and
161 # other has only an equal version requirement that satisfies this
162 # dependency.
163
164 def =~ other
165 unless Gem::Dependency === other
166 return unless other.respond_to?(:name) && other.respond_to?(:version)
167 other = Gem::Dependency.new other.name, other.version
168 end
169
170 return false unless name === other.name
171
172 reqs = other.requirement.requirements
173
174 return false unless reqs.length == 1
175 return false unless reqs.first.first == '='
176
177 version = reqs.first.last
178
179 requirement.satisfied_by? version
180 end
181
182 def match? name, version
183 return false unless self.name === name
184 return true if requirement.none?
185
186 requirement.satisfied_by? Gem::Version.new(version)
187 end
188
189 def matches_spec? spec
190 return false unless name === spec.name
191 return true if requirement.none?
192
193 requirement.satisfied_by?(spec.version)
194 end
195
196 ##
197 # Merges the requirements of +other+ into this dependency
198
199 def merge other
200 unless name == other.name then
201 raise ArgumentError,
202 "#{self} and #{other} have different names"
203 end
204
205 default = Gem::Requirement.default
206 self_req = self.requirement
207 other_req = other.requirement
208
209 return self.class.new name, self_req if other_req == default
210 return self.class.new name, other_req if self_req == default
211
212 self.class.new name, self_req.as_list.concat(other_req.as_list)
213 end
214
215 def matching_specs platform_only = false
216 matches = Gem::Specification.find_all { |spec|
217 self.name === spec.name and # TODO: == instead of ===
218 requirement.satisfied_by? spec.version
219 }
220
221 if platform_only
222 matches.reject! { |spec|
223 not Gem::Platform.match spec.platform
224 }
225 end
226
227 matches = matches.sort_by { |s| s.sort_obj } # HACK: shouldn't be needed
228 end
229
230 ##
231 # True if the dependency will not always match the latest version.
232
233 def specific?
234 @requirement.specific?
235 end
236
237 def to_specs
238 matches = matching_specs true
239
240 # TODO: check Gem.activated_spec[self.name] in case matches falls outside
241
242 if matches.empty? then
243 specs = Gem::Specification.all_names.join ", "
244 error = Gem::LoadError.new "Could not find #{name} (#{requirement}) amongst [#{specs}]"
245 error.name = self.name
246 error.requirement = self.requirement
247 raise error
248 end
249
250 # TODO: any other resolver validations should go here
251
252 matches
253 end
254
255 def to_spec
256 matches = self.to_specs
257
258 matches.find { |spec| spec.activated? } or matches.last
259 end
260 end