Gitlab : Backup Restore error

When i was try to restore a backup in gitlab, it' s fails and i am getting this error please help

rake aborted!
PG::ConnectionBad: could not connect to server: No such file or directory
    Is the server running locally and accepting
    connections on Unix domain socket " /var/opt/gitlab/postgresql/.s.PGSQL.5432" ?
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/db.rake:27:in `block (3 levels) in < top (required)> ' 
/opt/gitlab/embedded/service/gitlab-rails/lib/tasks/gitlab/backup.rake:52:in `block (3 levels) in < top (required)> ' 
/opt/gitlab/embedded/bin/bundle:23:in `load' 
/opt/gitlab/embedded/bin/bundle:23:in `< main> ' 
Tasks: TOP =>  gitlab:db:drop_tables
(See full trace by running task with --trace)