Hi Ravi,
This error is typical of a scenario where the proxy/Hue has been configured and has timed out the connection according to its own internal timeout settings before the destination server has been able to respond to a request.
I would suggest reviewing the configuration to ensure that your timeout values are sufficient to allow the destination server to respond (or reach its own internal timeout).
To determine whether increasing Hue's configured timeouts is appropriate check the follow:
For older versions of Cloudera Manager this must be set as a safety valve:
1. From Cloudera Manager, click Hue service > Configuration
2. Enter: Hue Service Advanced Configuration Snippet (Safety Valve) for hue_safety_valve.ini in the search field.
3. Add the following:
[impala]
query_timeout_s=600
[beeswax]
server_conn_timeout=600
For newer versions of Cloudera Manager, this can be configured using the configuration options for Hue in Cloudera Manager: Hue service > Configuration > HiveServer2 and Impala Thrift Connection Timeout