Oracle database exception due to missing x permission for Bdump directory

rhel6.3 x64bit, Oracle 11.2.0.4 x64bit

[Email protected] test]$ pwd/u01/app/oracle/diag/rdbms/test/test[[email protected] test]$ chmod u-x trace[[email  Protected] test]$ lltotal 100drwxr-x---.  2 Oracle Oinstall 4096 alertdrwxr-x---.  2 Oracle Oinstall 4096 cdumpdrwxr-x---. 2 Oracle Oinstall 4096 hmdrwxr-x---.  Oracle Oinstall 4096 Jan 8 20:58 incidentdrwxr-x---.  2 Oracle Oinstall 4096 incpkgdrwxr-x---.  2 Oracle Oinstall 4096 irdrwxr-x---.  2 Oracle Oinstall 4096 Jan 8 20:58 lckdrwxr-x---.  2 Oracle Oinstall 4096 metadatadrwxr-x---.  2 Oracle Oinstall 4096 metadata_dgifdrwxr-x---.  2 Oracle Oinstall 4096 metadata_pvdrwxr-x---.  2 Oracle Oinstall 4096 Jan 8 20:58 stagedrwxr-x---. 2 Oracle Oinstall 4096 Jan 8 20:58 sweepdrw-r-x---. Oracle Oinstall 49152 Jan 8 20:58 Trace---> Missing x permission, the directory is the Bdump directory (the directory specified by Background_dump_dest)

Here's what happens to DB server's native login sqlplus:

[Email protected] ~]$ sqlplus  /As Sysdbsql*plus:release 11.2.0.4.0 Production on Thu Jan 8 21:04:16 2015Copyright ( c) 1982, Oracle.  All rights reserved. Error:ora-12547:tns:lost Contactenter User-name:  

3 minutes or so before the above error is reported.
The DB is connected from the Oracle DB Client (PL/SQL Developer) and is reported:

Ora-12537:tns:connection closed

At this point, the trace directory is not going to go in:

[Email protected] test]$ CD trace-bash:cd:trace:permission denied

The solution to this problem is actually simple:

[Email protected] test]$ chmod u+x Trace

Oracle database exception due to missing x permission for Bdump directory