Oracle Network Products Troubleshooting Guide

Example of a Trace File

In the following example, the SQLNET.ORA file includes the following line:

TRACE_LEVEL_CLIENT = ADMIN

The following trace file is the result of a connection attempt that failed because the hostname is invalid.

The trace output is a combination of debugging aids for Oracle specialists and English information for network administrators. Several key events can be seen by analyzing this output from beginning to end:

The client describes the outgoing data in the connect descriptor used to contact the server.

An event is received (connection request).

A connection is established over the available transport (in this case TCP/IP).

The connection is refused by the application, which is the listener.

The trace file shows the problem, as follows:
-<FATAL?>- *** hostname lookup failure! ***

Error 12545 is reported back to the client.

If you look up Error 12545

of this guide, you will find the following description:

ORA-12545 TNS:Name lookup failure

Cause: A protocol specific ADDRESS parameter cannot be resolved.

Action: Ensure the ADDRESS parameters have been entered correctly; the most likely incorrect value is the node name.

Sample Trace File

The following trace file has been annotated to make it easier to understand:

--- TRACE CONFIGURATION INFORMATION FOLLOWS ---
New trace stream is "/private1/oracle/trace_admin.trc"
New trace level is 6
--- TRACE CONFIGURATION INFORMATION ENDS ---

--- PARAMETER SOURCE INFORMATION FOLLOWS ---
Attempted load of system pfile source /private1/oracle/network/admin/sqlnet.ora
Parameter source was not loaded
Error stack follows:
NL-00405: cannot open parameter file

Attempted load of local pfile source /home/ginger/.sqlnet.ora
Parameter source loaded successfully

 -> PARAMETER TABLE LOAD RESULTS FOLLOW <-
Some parameters may not have been loaded
See dump for parameters which loaded OK
 -> PARAMETER TABLE HAS THE FOLLOWING CONTENTS <-
  TRACE_DIRECTORY_CLIENT = /private1/oracle
  trace_level_client = ADMIN
  TRACE_FILE_CLIENT = trace_admin
--- PARAMETER SOURCE INFORMATION ENDS ---

--- LOG CONFIGURATION INFORMATION FOLLOWS ---
Attempted open of log stream "/private1/oracle/sqlnet.log"
Successful stream open
--- LOG CONFIGURATION INFORMATION ENDS ---

Unable to get data from navigation file tnsnav.ora
local names file is /home/ginger/.tnsnames.ora
system names file is /etc/tnsnames.ora
initial retry timeout for all servers is 500 csecs
max request retries per server is 2
default zone is [root]
Using nncin2a() to build connect descriptor for (possibly remote) database.
initial load of /home/ginger/.tnsnames.ora
-<ERROR>- failure, error stack follows
-<ERROR>- NL-00405: cannot open parameter file
-<ERROR>-   NOTE: FILE CONTAINS ERRORS, SOME NAMES MAY BE MISSING

initial load of /etc/tnsnames.ora
-<ERROR>- failure, error stack follows
-<ERROR>- NL-00427: bad list
-<ERROR>-   NOTE: FILE CONTAINS ERRORS, SOME NAMES MAY BE MISSING

Inserting IPC address into connect descriptor returned from nncin2a().
Calling address: (DESCRIPTION=(CONNECT_DATA=(SID=trace)(CID=(PROGRAM=)(HOST=lala)
 (USER=ginger)))(ADDRESS_LIST=(ADDRESS=(PROTOCOL=ipc
 (KEY=bad_host))(ADDRESS=(PROTOCOL=tcp)(HOST=lavender)
 (PORT=1521))))
Getting local community information
Looking for local addresses setup by nrigla
No addresses in the preferred address list
TNSNAV.ORA is not present. No local communities entry.
Getting local address information
Address list being processed...
No community information so all addresses are "local"
Resolving address to use to call destination or next hop
Processing address list...
No community entries so iterate over address list
This a local community access
Got routable address information
Making call with following address information: (DESCRIPTION=(EMPTY=0)(ADDRESS=(PROTOCOL=ipc)(KEY=bad_host)))
Calling with outgoing connect data (DESCRIPTION=(CONNECT_DATA=(SID=trace)(CID=(PROGRAM=)(HOST=lala)
 (USER=ginger)))(ADDRESS_LIST=(ADDRESS=(PROTOCOL=tcp)
 (HOST=lavender)(PORT=1521))))
(DESCRIPTION=(EMPTY=0)(ADDRESS=(PROTOCOL=ipc)(KEY=bad_host)))
 KEY = bad_host
connecting...
opening transport...
-<ERROR>- sd=8, op=1, resnt[0]=511, resnt[1]=2, resnt[2]=0
-<ERROR>- unable to open transport
-<ERROR>- nsres: id=0, op=1, ns=12541, ns2=12560; nt[0]=511, nt[1]=2, nt[2]=0
connect attempt failed
Call failed...
Call made to destination
Processing address list so continuing
Getting local community information
Looking for local addresses setup by nrigla
No addresses in the preferred address list
TNSNAV.ORA is not present. No local communities entry.
Getting local address information
Address list being processed...
No community information so all addresses are "local"
Resolving address to use to call destination or next hop
Processing address list...
No community entries so iterate over address list
This a local community access
Got routable address information


Making call with following address information: (DESCRIPTION=(EMPTY=0)(ADDRESS=(PROTOCOL=tcp)
 (HOST=lavender)(PORT=1521)))
Calling with outgoing connect data (DESCRIPTION=(CONNECT_DATA=(SID=trace)(CID=(PROGRAM=)(HOST=lala)
 (USER=ginger)))(ADDRESS_LIST=(ADDRESS=(PROTOCOL=tcp)
 (HOST=lavender)(PORT=1521))))
(DESCRIPTION=(EMPTY=0)(ADDRESS=(PROTOCOL=tcp)
 (HOST=lavender)(PORT=1521)))
port resolved to 1521
looking up IP addr for host: lavender

-<FATAL?>-  *** hostname lookup failure! ***

-<ERROR>- nsres: id=0, op=13, ns=12545, ns2=12560; nt[0]=515, nt[1]=0, nt[2]=0
Call failed...
Exiting NRICALL with following termination result -1
-<ERROR>-  error from nricall
-<ERROR>-    nr err code: 12206
-<ERROR>-    ns main err code: 12545
-<ERROR>-    ns (2)  err code: 12560
-<ERROR>-    nt main err code: 515
-<ERROR>-    nt (2)  err code: 0
-<ERROR>-    nt OS   err code: 0
-<ERROR>- Couldn't connect, returning 12545

Most tracing is very similar to this. If you have a basic understanding of the events the components perform, you can identify the probable cause of an error in the text of the trace.

Note: Customers who have a beta version of the new Oracle Trace product installed on a Solaris or Sequent machine will see additional files in the trace directory beside the standard .TRC files. These .CDF and .DAT files are created by Oracle Trace. They are in an encoded binary format and are not readable without Oracle Enterprise Manager, which is not yet released. To save disk space, these files should be removed.