TN broken pipe error

When we try to open the TN it gives error like:
Could not get profile summary (username=******).
Could not retrieve Custom Fields from database
(0) java.sql.SQLException: [wm-cjdbc33-0069][Oracle JDBC Driver]Broken pipe
(1) java.sql.SQLException: [wm-cjdbc33-0069][Oracle JDBC Driver]Broken pipe.
We can connect to TN sometimes and sometimes it throws the above error?
Does anyone know the reason of it?

Can you try with Data Direct Connect JDBC driver, version 3.3 build number 79 ?

when can you connect to TN? check for any scheduled outage (if any). After running db scripts for TN, by any chance did u restart your IS? have you upgraded your TN?