DBI connect('database=koha_library;host=localhost;port=3306','koha_library',...) failed: Access denied for user 'koha_library'@'localhost' (using password: YES) at /usr/share/perl5/DBIx/Class/Storage/DBI.pm line 1517. DBIx::Class::Storage::DBI::catch {...} (): DBI Connection failed: Access denied for user 'koha_library'@'localhost' (using password: YES) at /usr/share/perl5/DBIx/Class/Storage/DBI.pm line 1520. at /usr/share/koha/lib/Koha/Database.pm line 107 dpkg: error processing package koha-common (--configure): installed koha-common package post-installation script subprocess returned error exit status 255 Errors were encountered while processing: koha-common E: Sub-process /usr/bin/dpkg returned an error code (1)
This is not a bug, it looks like your database server has gone away. Please ask about these sorts of issue to your support provider, or on the mailing list