Additional info:

I have full disk encryption, but vagrant used to work for me (about 6 months ago?) and it's the same computer although I'm now on 14.04 instead of 13.* , since then- is this a new thing, that it's known not to work on fully encrypted disks but just on Trusty Tahr specifically?

I was able to complete vagrant up with NFS shares off, but unfortunately still with errors. 

While there is a server running at http://127.0.0.1:8080/ I get File not found: /vagrant/mediawiki/index.php. Alas! 

Output of vagrant up:

Stderr from the command:

stdin: is not a tty
Error: composer install --optimize-autoloader returned 1 instead of one of [0]
Error: /Stage[main]/Mediawiki/Php::Composer::Install[/vagrant/mediawiki]/Exec[composer-install--vagrant-mediawiki]/returns: change from notrun to 0 failed: composer install --optimize-autoloader returned 1 instead of one of [0]
Error: /usr/local/bin/multiversion-install wiki admin --dbname wiki --dbpass vagrant --dbuser root --pass vagrant --scriptpath /w --server http://127.0.0.1:8080 --confpath /vagrant/settings.d/wikis/wiki 
 returned 1 instead of one of [0]
Error: /Stage[main]/Mediawiki/Mediawiki::Wiki[devwiki]/Exec[wiki_setup]/returns: change from notrun to 0 failed: /usr/local/bin/multiversion-install wiki admin --dbname wiki --dbpass vagrant --dbuser root --pass vagrant --scriptpath /w --server http://127.0.0.1:8080 --confpath /vagrant/settings.d/wikis/wiki 
 returned 1 instead of one of [0]
Warning: /Stage[main]/Mediawiki/Mediawiki::Wiki[devwiki]/Exec[wiki_include_extra_settings]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Visualeditor/Mediawiki::Extension[VisualEditor]/Mediawiki::Extension::Browsertests[VisualEditor]/Browsertests::Bundle[VisualEditor_browsertests_bundle]/Ruby::Bundle[VisualEditor_browsertests_bundle]/File[/vagrant/mediawiki/extensions/VisualEditor/modules/ve-mw/tests/browser/.bundle/config]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Visualeditor/Mediawiki::Extension[VisualEditor]/Mediawiki::Extension::Browsertests[VisualEditor]/Browsertests::Bundle[VisualEditor_browsertests_bundle]/Ruby::Bundle[VisualEditor_browsertests_bundle]/Exec[bundle_install_VisualEditor_browsertests_bundle]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Codeeditor/Mediawiki::Extension[CodeEditor]/Git::Clone[mediawiki/extensions/CodeEditor]/Exec[git_clone_mediawiki/extensions/CodeEditor]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Parserfunctions/Mediawiki::Extension[ParserFunctions]/Git::Clone[mediawiki/extensions/ParserFunctions]/Exec[git_clone_mediawiki/extensions/ParserFunctions]: Skipping because of failed dependencies
Warning: /Stage[main]/Mediawiki/Exec[copy_LocalSettings]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Cite/Mediawiki::Extension[Cite]/Git::Clone[mediawiki/extensions/Cite]/Exec[git_clone_mediawiki/extensions/Cite]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Visualeditor/Mediawiki::Extension[VisualEditor]/Git::Clone[mediawiki/extensions/VisualEditor]/Exec[git_clone_mediawiki/extensions/VisualEditor]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Templatedata/Mediawiki::Extension[TemplateData]/Git::Clone[mediawiki/extensions/TemplateData]/Exec[git_clone_mediawiki/extensions/TemplateData]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Wikieditor/Mediawiki::Extension[WikiEditor]/Git::Clone[mediawiki/extensions/WikiEditor]/Exec[git_clone_mediawiki/extensions/WikiEditor]: Skipping because of failed dependencies
Warning: /Stage[main]/Browsertests/Mediawiki::User[Selenium_user]/Exec[mediawiki_user_Selenium_user]: Skipping because of failed dependencies
Warning: /Stage[main]/Mediawiki::Parsoid/Mediawiki::Extension[Parsoid]/Git::Clone[mediawiki/extensions/Parsoid]/Exec[git_clone_mediawiki/extensions/Parsoid]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Geshi/Mediawiki::Extension[SyntaxHighlight_GeSHi]/Git::Clone[mediawiki/extensions/SyntaxHighlight_GeSHi]/Exec[git_clone_mediawiki/extensions/SyntaxHighlight_GeSHi]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Wikieditor/Mediawiki::Extension[WikiEditor]/Mediawiki::Settings[WikiEditor]/File[/vagrant/settings.d/puppet-managed/10-WikiEditor.php]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Codeeditor/Mediawiki::Extension[CodeEditor]/Mediawiki::Settings[CodeEditor]/File[/vagrant/settings.d/puppet-managed/10-CodeEditor.php]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Cite/Mediawiki::Extension[Cite]/Mediawiki::Settings[Cite]/File[/vagrant/settings.d/puppet-managed/10-Cite.php]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Visualeditor/Mediawiki::Extension[VisualEditor]/Mediawiki::Settings[VisualEditor]/File[/vagrant/settings.d/puppet-managed/10-VisualEditor.php]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Templatedata/Mediawiki::Extension[TemplateData]/Mediawiki::Settings[TemplateData]/File[/vagrant/settings.d/puppet-managed/10-TemplateData.php]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Geshi/Mediawiki::Extension[SyntaxHighlight_GeSHi]/Mediawiki::Settings[SyntaxHighlight_GeSHi]/File[/vagrant/settings.d/puppet-managed/10-SyntaxHighlight_GeSHi.php]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Parserfunctions/Mediawiki::Extension[ParserFunctions]/Mediawiki::Settings[ParserFunctions]/File[/vagrant/settings.d/puppet-managed/10-ParserFunctions.php]: Skipping because of failed dependencies
Warning: /Stage[main]/Mediawiki::Parsoid/Mediawiki::Extension[Parsoid]/Mediawiki::Settings[Parsoid]/File[/vagrant/settings.d/puppet-managed/10-Parsoid.php]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Scribunto/Mediawiki::Extension[Scribunto]/Git::Clone[mediawiki/extensions/Scribunto]/Exec[git_clone_mediawiki/extensions/Scribunto]: Skipping because of failed dependencies
Warning: /Stage[main]/Role::Scribunto/Mediawiki::Extension[Scribunto]/Mediawiki::Settings[Scribunto]/File[/vagrant/settings.d/puppet-managed/10-Scribunto.php]: Skipping because of failed dependencies
Warning: /Stage[main]/Mediawiki::Jobrunner/Service[jobrunner]: Skipping because of failed dependencies
Warning: /Stage[main]/Apache/Service[apache2]: Skipping because of failed dependencies