Thêm một nút quản lý là đơn giản. Thứ nhất, cài đặt các khách hàng quản lý trên các nút mới (tham khảo công thức ở chương 1). Thứ hai, sửa đổi các tập tin , như thể hiện trước đó trong công thức này để thêm các nút quản lý mới, và sao chép tập tin này mới để cả hai nút quản lý. Cuối cùng, ngăn chặn các nút quản lý hiện có và bắt đầu mới bằng cách sử dụng các lệnh sau đây: Đối với nút quản lý hiện có,. | Chapter 4 773 tcp open submit 3306 tcp open mysql Nmap finished 1 IP address 1 host up scanned in seconds Host resolution If you are not using IP addresses in the file strongly recommended ensure that you have all of the hosts involved in the cluster in a etc hosts file to ensure that a simple DNS outages does not take down the entire cluster. For example your etc hosts may look as follows root@node1 mysql-cluster cat etc hosts Do not remove the following line or various programs that require network functionality will fail. node1 localhost 1 localhost6 node1 node2 node3 node4 node5 Memory It is extremely common for IndexMemory and DataMemory to use more memory than the system s free memory. This is commonly caused by running another process on the same server as a storage node such as a standard MySQL server which may use a large amount of RAM while executing a specific query . It is recommended that storage nodes only run the storage node processes. In the case that this becomes a regular problem it is possible to tune the Linux kernel out of memory OOM killer this is the piece of code which decides which process to kill in the case of running out of physical memory to kill another process and not the ndbd process. There is a value proc pid oom-adj which ranges from -16 to 15 -17 means never kill this process . The following bash snippet can be used to run after a storage node has started to significantly reduce the change of the OOM killer killing ndbd root@node1 mysql-cluster for pid in pidof ndbd do echo -10 proc pid oom_adj done root@node1 mysql-cluster However it is still recommended not to come near to running out of physical memory on a storage node 129 129 MySQL Cluster Troubleshooting Seeking help In this recipe we will cover what to do when help is .