ERROR: Can not connect to monitor daemon! Problems

Use yum install mysql-mmm for installation.

After the mmm software is installed, the configuration is completed, but the following error is reported when the/usr/sbin/mmm_control show command is executed:

ERROR: Can not connect to monitor daemon!

1. Check that the agent on db1 and db2 is enabled.

2. Check iptables. It is also good. No filtering is performed.

3. Check the mmm log report and report that the socket connecting to port 9988 of 127.0.0.1 is not created successfully. Ask for help from colleagues to analyze the following two situations:

(1): the socket in mmm_common.conf is not set. You need to add the following Configuration:

<Socket>

Type plain

Cert_file/etc/mysql-mmm/ssl_crt.pem

Key_file/etc/mysql-mmm/ssl_key.pem

Ca_file/etc/mysql-mmm/ca_crt.pem

</Socket>

Then restart the monitor service. check/usr/sbin/mmm_control show.

(2): The original debug monitor is not completely stopped, so starting a new monitor will fail, use netstat-tupln | grep 9988 or netstat-anp | grep 9988 to check whether the port is enabled.

[PS]: in linux, chown like mmm_control should be granted the mmmd account permission.