I want to update a two gateways cluster from version 8.2 to 9.0. While reading how to do so I came across with this two sentences in two different sections of the document:
- Cluster Upgrade - Split the cluster: Configure the Primary node to block database access and replication traffic from the Secondary node (use iptables command and modify /etc/sysconfig/iptables configuration)
- Cluster Upgrade – Establish Replication: Configure the Primary node to permit the Secondary node to re-connect for database purposes (use iptables command and modify /etc/sysconfig/iptables configuration)
It's the first time I work with iptables and I'm not quite sure how to accomplish this two steps. Do I have to execute in first process this?
$ iptables -A INPUT -p tcp -m tcp --sport 3306 -j REJECT
And when doing the second one, execute this?
$ iptables -A INPUT -p tcp -m tcp --sport 3306 -j ACCEPT
Thanks in advance.