REAL TIME AI ORACLE DATABASE PROBLEM AND SOLUTIONS

Thursday, April 11, 2019

How to check and stop firewall on Oracle Linux 6.

How to check and stop firewall on Oracle Linux 6

[root@pri ~]# service iptables status
Table: nat
Chain PREROUTING (policy ACCEPT)
num target prot opt source destination

Chain INPUT (policy ACCEPT)
num target prot opt source destination

Chain OUTPUT (policy ACCEPT)
num target prot opt source destination

Chain POSTROUTING (policy ACCEPT)
num target prot opt source destination
1 MASQUERADE tcp -- 192.168.122.0/24 !192.168.122.0/24 masq ports: 1024-65535
2 MASQUERADE udp -- 192.168.122.0/24 !192.168.122.0/24 masq ports: 1024-65535
3 MASQUERADE all -- 192.168.122.0/24 !192.168.122.0/24

Table: mangle
Chain PREROUTING (policy ACCEPT)
num target prot opt source destination

Chain INPUT (policy ACCEPT)
num target prot opt source destination

Chain FORWARD (policy ACCEPT)
num target prot opt source destination

Chain OUTPUT (policy ACCEPT)
num target prot opt source destination

Chain POSTROUTING (policy ACCEPT)
num target prot opt source destination
1 CHECKSUM udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:68 CHECKSUM fill

Table: filter
Chain INPUT (policy ACCEPT)
num target prot opt source destination
1 ACCEPT udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:53
2 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:53
3 ACCEPT udp -- 0.0.0.0/0 0.0.0.0/0 udp dpt:67
4 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 tcp dpt:67
5 ACCEPT all -- 0.0.0.0/0 0.0.0.0/0 state RELATED,ESTABLISHED
6 ACCEPT icmp -- 0.0.0.0/0 0.0.0.0/0
7 ACCEPT all -- 0.0.0.0/0 0.0.0.0/0
8 ACCEPT tcp -- 0.0.0.0/0 0.0.0.0/0 state NEW tcp dpt:22
9 REJECT all -- 0.0.0.0/0 0.0.0.0/0 reject-with icmp-host-prohibited

Chain FORWARD (policy ACCEPT)
num target prot opt source destination
1 ACCEPT all -- 0.0.0.0/0 192.168.122.0/24 state RELATED,ESTABLISHED
2 ACCEPT all -- 192.168.122.0/24 0.0.0.0/0
3 ACCEPT all -- 0.0.0.0/0 0.0.0.0/0
4 REJECT all -- 0.0.0.0/0 0.0.0.0/0 reject-with icmp-port-unreachable
5 REJECT all -- 0.0.0.0/0 0.0.0.0/0 reject-with icmp-port-unreachable
6 REJECT all -- 0.0.0.0/0 0.0.0.0/0 reject-with icmp-host-prohibited

Chain OUTPUT (policy ACCEPT)
num target prot opt source destination

[root@pri ~]#
[root@pri ~]#
[root@pri ~]# service iptables stop
iptables: Setting chains to policy ACCEPT: nat mangle filte[ OK ]
iptables: Flushing firewall rules: [ OK ]
iptables: Unloading modules: [ OK ]
[root@pri ~]#
[root@pri ~]#
[root@pri ~]#
[root@pri ~]# service iptables status
iptables: Firewall is not running.

[root@pri ~]#

How can I access Oracle database from Python language using unique way ?

How can I access Oracle database from Python language?

we usually get issue while working with oracle database using python langaugae . The big issue how to connect with database .

There are many articles are available but when you run inti issue very few helps on out .
if you are here then you issue is solved to how to connect with oracle database using python langaugae ?

* First you need to install python (in my case python version is 3.7.2)

* Install Oracle client (in my case oracle 18c)

* Update network configuration file tnanames.ora using db details

* Stop firewall on linux (db install on linux in my case )

* Install oracle cx_Oracle module in python using pip command as below

* Start listener (db service) on oracle server

save the file as oracle_test.py

from future import print_function

import cx_Oracle

# Connect as user "hr" with password "hr" to the "ind" service running on this server.
connection = cx_Oracle.connect("hr", "hr", "192.168.43.68/ind")

cursor = connection.cursor()
cursor.execute("""
SELECT first_name, last_name
FROM employees
WHERE department_id = :did AND employee_id > :eid""",
did = 55,
eid = 180)
for fname, lname in cursor:
print("Values:", fname, lname)

* you can upgrade pip module using below snapshot:

Wednesday, April 10, 2019

Oracle database network configuration files - listener.ora and tnsnames.ora

DB Network Configuration file

tnsnames.ora

[oracle@pri admin]$ pwd
/u01/app/oracle/product/18.0.0/db/network/admin

[oracle@pri admin]$

[oracle@pri admin]$ cat tnsnames.ora
# tnsnames.ora Network Configuration File: /u01/app/oracle/product/18.0.0/db/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.

IND =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.43.68)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = IND)
)
)

##LISTENER_IND =
## (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.43.68)(PORT = 1521))

USA =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.43.69)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = USA)
)
)

listener.ora

[oracle@pri admin]$ cat listener.ora
# listener.ora Network Configuration File: /u01/app/oracle/product/18.0.0/db/network/admin/listener.ora
# Generated by Oracle configuration tools.

LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.43.68)(PORT = 1521))
(ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
)
)

SID_LIST_LISTENER =
(SID_LIST =
(SID_DESC =
(GLOBAL_DBNAME = IND)
(ORACLE_HOME = /u01/app/oracle/product/18.0.0/db)
(SID_NAME = IND)
)
(SID_DESC =
(GLOBAL_DBNAME = USA)
(ORACLE_HOME = /u01/app/oracle/product/18.0.0/db)
(SID_NAME = USA)
)
)

ADR_BASE_LISTENER = /u01/app/oracle

[oracle@pri admin]$

[oracle@pri ~]$ lsnrctl status

LSNRCTL for Linux: Version 18.0.0.0.0 - Production on 10-APR-2019 22:46:01

Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=192.168.43.68)(PORT=1521)))

STATUS of the LISTENER

------------------------

Alias LISTENER

Version TNSLSNR for Linux: Version 18.0.0.0.0 - Production

Start Date 10-APR-2019 17:03:30

Uptime 0 days 5 hr. 42 min. 30 sec

Trace Level off

Security ON: Local OS Authentication

SNMP OFF

Listener Parameter File /u01/app/oracle/product/18.0.0/db/network/admin/listener.ora

Listener Log File /u01/app/oracle/diag/tnslsnr/pri/listener/alert/log.xml

Listening Endpoints Summary...

(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=192.168.43.68)(PORT=1521)))

(DESCRIPTION=(ADDRESS=(PROTOCOL=ipc)(KEY=EXTPROC1521)))

Services Summary...

Service "IND" has 1 instance(s).

Instance "IND", status UNKNOWN, has 1 handler(s) for this service...

Service "USA" has 1 instance(s).

Instance "USA", status UNKNOWN, has 1 handler(s) for this service...

The command completed successfully

[oracle@pri ~]$