Oracle Turn on Slow monitoring

Phenomenon:

In an Oracle database, it is very slow to use lsnrctl to turn on, turn off listening, or to view the listening state, so that the action can be done immediately by means of a broken network.

When a client connects to a database using Plsql and other methods, it is also very slow, and it can also be done by switching network state.

Divided into two levels:

1. The monitoring itself has a problem

Turn off the listening log and clean up the listening log

A. Turn off the listening log

Shell command line login to Oracle user, enter LSNRCTL to enter the listening command line.

Show Log_status View the Listening log status, "set to On" means open, "set to off" means close

Set Log_status off Listen log

Save_config Save Configuration

B. Clean up the Listening log

The Listening log (with the word "log" in the name) may be in the following location, and it is recommended to clean or rename after backup.

/u01/app/oracle/diag/tnslsnr/distance/listener/alert

/u01/app/oracle/diag/tnslsnr/distance/listener/trace

/u01/app/oracle/diag/rdbms/orcl/orcl/alert

(The location may vary depending on the installation, please find the corresponding directory of your machine according to the actual situation)

Reference: https://zhidao.baidu.com/question/616289319368834692.html (Stop listening)

10195493 (listening log location)

2. Server Network configuration issues

There may be a problem with the DNS resolution file, modify the database server's/etc/resolv.conf, the "nameserver xxx.xxx.xxx.xxx" this line commented out

Troubleshooting and conclusion reference from http://www.itpub.net/thread-1784287-1-1.html

In the process of solving the above problems, there is an episode, because their CentOS build too long forgotten the root password, reference https://www.linuxidc.com/Linux/2018-01/150211.htm modified the CentOS password.

CentOS6 change root password, pro-test effective, of course, remember to take a snapshot of the virtual machine before changing.

Oracle Turn on Slow monitoring