TNS-12564: TNS:connection refused

Question

Hi,
I have some PHP applications which connect to Oracle database.
I sometime receive the following error message.
Fatal NI connect error 12516, connecting to:
(DESCRIPTION=(CONNECT_DATA=(SERVICE_NAME=)(CID=(PROGRAM=httpd)(HOST=r33188.ovh.net)(USER=nobody)))(ADDRESS=(PROTOCOL=TCP)(HOST=178.32.113.43)(PORT=1521)))
VERSION INFORMATION:
     TNS for Linux: Version 10.2.0.1.0 - Production
     TCP/IP NT Protocol Adapter for Linux: Version 10.2.0.1.0 - Production
Time: 29-JUL-2010 18:01:45
Tracing not turned on.
Tns error struct:
ns main err code: 12564
TNS-12564: TNS:connection refused
ns secondary err code: 0
nt main err code: 0
nt secondary err code: 0
nt OS err code: 0
I already had that error message in the past. At that time, I looked at the V$RESOURCE_LIMIT view and I saw session and process parameters were too small so I increased its.
Now, I checked again to these parameters and values never went nearly the max values.
RESOURCE_NAME     CURRENT_UTILIZATION     MAX_UTILIZATION     INITIAL_ALLOCATION     LIMIT_VALUE
processes     21     183     400     400
sessions     29     191     445     445
enqueue_locks     13     23     5470     5470
enqueue_resources     13     44     2176     UNLIMITED
ges_procs     0     0     0     0
ges_ress     0     0     0     UNLIMITED
ges_locks     0     0     0     UNLIMITED
ges_cache_ress     0     0     0     UNLIMITED
ges_reg_msgs     0     0     0     UNLIMITED
ges_big_msgs     0     0     0     UNLIMITED
ges_rsv_msgs     0     0     0     0
gcs_resources     0     0     0     0
gcs_shadows     0     0     0     0
dml_locks     0     73     1956     UNLIMITED
temporary_table_locks     0     3     UNLIMITED     UNLIMITED
transactions     1     6     489     UNLIMITED
branches     0     0     489     UNLIMITED
cmtcallbk     0     1     489     UNLIMITED
sort_segment_locks     5     8     UNLIMITED     UNLIMITED
max_rollback_segments     11     11     489     65535
max_shared_servers     4     7     UNLIMITED     UNLIMITED
parallel_max_servers     0     0     0     3600
Is it possible it can from another thing ? What is the best way to never have this error message again ? What is max value for sessions and processes that Oracle can support ?
Thanks in advance,
Best regards.

Answer 1

Why do I am having (HOST=178.32.113.43)(PORT=1521) in the error message? I am using only the DNS name.
my tnsnames.ora file:
NV =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = dns_name)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = NV)
and in my php connection function I also use the DNS name as the host and username/password like:
$connect = ocilogon($username, $password, 'dns_name');
Should I connect in another way ? like:
$ora_host='(DESCRIPTION =(ADDRESS =(PROTOCOL = TCP)(HOST = dns_name)(PORT = 1521))(CONNECT_DATA =(SID = NV)))';
$connect = ocilogon($username, $password, $ora_host);