Reproduction steps:

• Install phabricator and leave phabricator.base-uri empty
• enable ssh service according to diffusion_hosting
• ssh -T pha_host

Expected result:

• ssh login successfully

Actual result:

• Error: phabricator Permission denied (publickey,keyboard-interactive)

Version:

• phabricator eac49e421a4192218e491662c51ef5fa9c7a8e00 (Thu, Nov 24)
• arcanist fad85844314b151994769a461825c90f7400c145 (Oct 22 2016)
• phutil 19d250fe8a8ad55f38d29d597bf219a9c92bf152 (Thu, Nov 24)

Analysis:

• Without base-uri defined, line 12 in phabricator/scripts/ssh/ssh-auth.php will raise exception:

12   $keys = id(new PhabricatorAuthSSHKeyQuery())
13     ->setViewer(PhabricatorUser::getOmnipotentUser())
14     ->withIsActive(true)
15     ->execute();

O:9:"Exception":7:{s:10:"*message";s:64:"Define 'phabricator.base-uri' in your configuration to continue.";s:17:"Exceptionstring";s:0:"";s:7:"*code";i:0;s:7:"*file";s:67:"/var/www/html/phabricator/src/infrastructure/env/PhabricatorEnv.php";s:7:"*line";i:473;s:16:"Exceptiontrace"

Suggestion:

• Why ssh service depend on phabricator.base-uri?
• If this is not a bug, please add phabricator.base-uri configuration in diffusion_hosting as a necessary requirement