Using traceroute with a specific port

This is how you can use traceroute for a specific port:

traceroute -T -p 3306 10.20.41.1

or the same:

traceroute --tcp -p 3306 10.20.41.1

How to solve ‘Can’t locate DBD/mysql.pm’

As simple as:

yum install perl-DBD-mysql

1. Download the repository packages:

wget https://repo.percona.com/apt/percona-release_0.1-3.$(lsb_release -sc)_all.deb

2. Install it:

dpkg -i percona-release_0.1-3.$(lsb_release -sc)_all.deb

3. Update the packages list:

apt-get update

4. Install

apt-get install percona-nagios-plugins

5. Grant the privileges:

GRANT USAGE, SELECT, REPLICATION CLIENT on *.* to 'test'@'localhost' IDENTIFIED BY 'password';

6. Test:

/usr/lib64/nagios/plugins/pmp-check-mysql-status -x wsrep_cluster_status -C == -T str -c non-Primary -l test -p password

curl -H "Origin: https://www.pydelion.com" \
https://static.pydelion.com/style/all.css -I  -v

fallocate -l 512M /mnt/swap ; \
dd if=/dev/zero of=/mnt/swap bs=512 count=1048576 \
 ; mkswap /mnt/swap ; swapon /mnt/swap ; swapon -s ; free -m

ansible MySQL replication fails to change master with the following error: ‘Sending passwords in plain text without SSL/TLS is extremely insecure.’

To fix the problem open /usr/lib64/python2.6/site-packages/MySQLdb/cursors.py and change:

defer_warnings = False

defer_warnings = True

This is ugly but it works.

Fire:

postmap /etc/postfix/virtual

Once done :

service restart postfix

That’s it.

Sometimes it’s needed to get only packages names only using rpm. This is how it can be done:

rpm -qa --qf "%{NAME}\n"

As simple as:

sed -e '/^$/N;/^\n$/D' <file>

Run:

set global relay_log_purge=1;

And flush the logs:

flush logs;