backups fail dumping database

I've recently converted from mysql to postgresql and running backups fail with:

sudo -u git -H bundle exec rake gitlab:backup:create RAILS_ENV=production
Dumping database ... 
Dumping PostgreSQL database gitlabhq_production ... [FAILED]
...

This results in a zero byte database.sql file in the backup archive.

Interestingly I can run gitlab which connects to the postgresql server fine.

sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production

System information
System:		
Current User:	git
Using RVM:	yes
RVM Version:	1.24.4
Ruby Version:	1.9.3p484
Gem Version:	2.1.11
Bundler Version:1.3.5
Rake Version:	10.3.1
Sidekiq Version:2.17.0

GitLab information
Version:	6.9.2
Revision:	e46b644
Directory:	/usr/local/home/git/gitlab
DB Adapter:	postgresql
URL:		https://gitlab.someserver
HTTP Clone URL:	https://gitlab.someserver/some-project.git
SSH Clone URL:	git@gitlab.someserver:some-project.git
Using LDAP:	yes
Using Omniauth:	no

GitLab Shell
Version:	1.9.3
Repositories:	/usr/local/home/git/repositories/
Hooks:		/usr/local/home/git/gitlab-shell/hooks/
Git:		/usr/bin/git

I'm trying to migrate to the omnibus 7.0 soon and need to get a good backup to import.

Is there a log file or any ideas?

TIA

Status changed to closed

What was your solution? I'm in the same situation and can't update to a newer version without a backup.

sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production

System information
System:         Ubuntu 14.04
Current User:   git
Using RVM:      no
Ruby Version:   2.1.2p95
Gem Version:    2.2.2
Bundler Version:1.6.3
Rake Version:   10.3.2
Sidekiq Version:3.3.0

GitLab information
Version:        7.8.1
Revision:       e2d785c
Directory:      /home/git/gitlab
DB Adapter:     postgresql
URL:            http://
HTTP Clone URL: http:///some-project.git
SSH Clone URL:  git@:some-project.git
Using LDAP:     no
Using Omniauth: no

GitLab Shell
Version:        2.5.4
Repositories:   /home/git/repositories/
Hooks:          /home/git/gitlab-shell/hooks/
Git:            /usr/bin/git

mentioned in commit 94f6ca5b

mentioned in merge request !14785