[oracle@testdb2 ~]$ tnsping testdb1 TNS Ping Utility for Linux: Version 11.2.0.3.0 - Production on 18-APR-2017 21:47:19 Copyright (c) 1997, 2011, Oracle. All rights reserved. Used parameter files: /opt/oracle/product/11.2.0.3/network/admin/sqlnet.ora Used TNSNAMES adapter to resolve the alias Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 10.0.76.54)(PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = testdb1))) TNS-12543: TNS:destination host unreachable
Solution: Common causes for the ORA-12543 error include:
If this is due to firewall issue then follow the instruction to disable firewall: [root@testdb1 ~]# service iptables save Saving firewall rules to /etc/sysconfig/iptables: [ OK ] [root@testdb1 ~]# service iptables stop Flushing firewall rules: [ OK ] Setting chains to policy ACCEPT: filter [ OK ] Unloading iptables modules: [ OK ] [root@testdb1 ~]# chkconfig iptables off
[oracle@testdb2 ~]$ tnsping testdb1 TNS Ping Utility for Linux: Version 11.2.0.3.0 - Production on 18-APR-2017 22:02:08 Copyright (c) 1997, 2011, Oracle. All rights reserved.
Used parameter files: /opt/oracle/product/11.2.0.3/network/admin/sqlnet.ora Used TNSNAMES adapter to resolve the alias Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 10.0.76.54)(PORT = 1521))) (CONNECT_DATA = (SERVICE_NAME = testdb1))) OK (0 msec) |