[Linaro-validation] Failed to access the lava instance from browser after installed locally

Hi, All

After I installed a lava instance and access it from browser, it says:

Bad Gateway

The proxy server received an invalid response from an upstream server. ------------------------------ Apache/2.2.22 (Ubuntu) Server at 192.168.9.109 Port 80

And in the /var/log/apache2/error.log file, I can see following information:

[Fri Jan 04 13:04:37 2013] [error] [client 192.168.9.109] uwsgi: unable to connect to uWSGI server: Permission denied [Fri Jan 04 13:04:37 2013] [debug] mod_deflate.c(615): [client 192.168.9.109] Zlib: Compressed 311 to 235 : URL /fastmodel

Anyone know why and how can I make it work again?