When I start the data nodeid 1 (10.1.1.103) of MySQL Cluster 8.0 on Ubuntu 22.04 LTS I am getting the following error:
# ndbd
Failed to open /sys/devices/system/cpu/cpu0/cache/index3/shared_cpu_list: No such file or directory
2023-01-02 17:16:55 [ndbd] INFO -- Angel connected to '10.1.1.102:1186'
2023-01-02 17:16:55 [ndbd] INFO -- Angel allocated nodeid: 2
When I start data nodeid 2 (10.1.1.105) I get the following error:
# ndbd
Failed to open /sys/devices/system/cpu/cpu0/cache/index3/shared_cpu_list: No such file or directory
2023-01-02 11:10:04 [ndbd] INFO -- Angel connected to '10.1.1.102:1186'
2023-01-02 11:10:04 [ndbd] ERROR -- Failed to allocate nodeid, error: 'Error: Could not alloc node id at 10.1.1.102:1186: Connection done from wrong host ip 10.1.1.105.'
The management node log file reports (on /var/lib/mysql-cluster/ndb_1_cluster.log):
2023-01-02 11:28:47 [MgmtSrvr] INFO -- Node 2: Initial start, waiting for 3 to connect, nodes [ all: 2 and 3 connected: 2 no-wait: ]
What is the relevance of failing to open: /sys/devices/system/cpu/cpu0/cache/index3/shared_cpu_list: No such file or directory?
Why is data node on 10.1.1.105 unable to allocate a nodeid?
I initially installed a single Management Node on 10.1.1.102:
wget https://dev.mysql.com/get/Downloads/MySQL-Cluster-8.0/mysql-cluster_8.0.31-1ubuntu22.04_amd64.deb-bundle.tar
tar -xf mysql-cluster_8.0.31-1ubuntu22.04_amd64.deb-bundle.tar
dpkg -i mysql-cluster-community-management-server_8.0.31-1ubuntu22.04_amd64.deb
mkdir /var/lib/mysql-cluster
vi /var/lib/mysql-cluster/config.ini
The configuration set up on config.ini:
[ndbd default]
# Options affecting ndbd processes on all data nodes:
NoOfReplicas=2 # Number of replicas
[ndb_mgmd]
# Management process options:
hostname=10.1.1.102 # Hostname of the manager
datadir=/var/lib/mysql-cluster # Directory for the log files
[ndbd]
hostname=10.1.1.103 # Hostname/IP of the first data node
NodeId=2 # Node ID for this data node
datadir=/usr/local/mysql/data # Remote directory for the data files
[ndbd]
hostname=10.1.1.105 # Hostname/IP of the second data node
NodeId=3 # Node ID for this data node
datadir=/usr/local/mysql/data # Remote directory for the data files
[mysqld]
# SQL node options:
hostname=10.1.1.102 # In our case the MySQL server/client is on the same Droplet as the cluster manager
I then started and killed the running server and created a systemd file for Cluster manager:
ndb_mgmd -f /var/lib/mysql-cluster/config.ini
pkill -f ndb_mgmd
vi /etc/systemd/system/ndb_mgmd.service
Adding the following configuration:
[Unit]
Description=MySQL NDB Cluster Management Server
After=network.target auditd.service
[Service]
Type=forking
ExecStart=/usr/sbin/ndb_mgmd -f /var/lib/mysql-cluster/config.ini
ExecReload=/bin/kill -HUP $MAINPID
KillMode=process
Restart=on-failure
[Install]
WantedBy=multi-user.target
I then reloaded the systemd daemon to apply the changes, started and enabled the Cluster Manager and checked its active status:
systemctl daemon-reload
systemctl start ndb_mgmd
systemctl enable ndb_mgmd
Here is the status of the Cluster Manager:
# systemctl status ndb_mgmd
● ndb_mgmd.service - MySQL NDB Cluster Management Server
Loaded: loaded (/etc/systemd/system/ndb_mgmd.service; enabled; vendor preset: enabled)
Active: active (running) since Sun 2023-01-01 08:25:07 CST; 27min ago
Main PID: 320972 (ndb_mgmd)
Tasks: 12 (limit: 9273)
Memory: 2.5M
CPU: 35.467s
CGroup: /system.slice/ndb_mgmd.service
└─320972 /usr/sbin/ndb_mgmd -f /var/lib/mysql-cluster/config.ini
Jan 01 08:25:07 nuc systemd[1]: Starting MySQL NDB Cluster Management Server...
Jan 01 08:25:07 nuc ndb_mgmd[320971]: MySQL Cluster Management Server mysql-8.0.31 ndb-8.0.31
Jan 01 08:25:07 nuc systemd[1]: Started MySQL NDB Cluster Management Server.
I then set up a data node on 10.1.1.103, installing dependencies, downloading the data node and setting up its config:
apt update && apt -y install libclass-methodmaker-perl
wget https://dev.mysql.com/get/Downloads/MySQL-Cluster-8.0/mysql-cluster_8.0.31-1ubuntu22.04_amd64.deb-bundle.tar
tar -xf mysql-cluster_8.0.31-1ubuntu22.04_amd64.deb-bundle.tar
dpkg -i mysql-cluster-community-data-node_8.0.31-1ubuntu22.04_amd64.deb
vi /etc/my.cnf
I entered the address of the Cluster Management Node in the configuration:
[mysql_cluster]
# Options for NDB Cluster processes:
ndb-connectstring=10.1.1.102 # location of cluster manager
I then created a data directory and started the node:
mkdir -p /usr/local/mysql/data
ndbd
This is when I got the "Failed to open" error result on data nodeid 1 (102.1.1.103):
# ndbd
Failed to open /sys/devices/system/cpu/cpu0/cache/index3/shared_cpu_list: No such file or directory
2023-01-02 17:16:55 [ndbd] INFO -- Angel connected to '10.1.1.102:1186'
2023-01-02 17:16:55 [ndbd] INFO -- Angel allocated nodeid: 2
UPDATED (2023-01-02)
Thank you @MauritzSundell. I corrected the (private) IP addresses above and no longer got:
# ndbd
Failed to open /sys/devices/system/cpu/cpu0/cache/index3/shared_cpu_list: No such file or directory
ERROR: Unable to connect with connect string: nodeid=0,10.1.1.2:1186
Retrying every 5 seconds. Attempts left: 12 11 10 9 8 7 6 5 4 3 2 1, failed.
2023-01-01 14:41:57 [ndbd] ERROR -- Could not connect to management server, error: ''
Also @MauritzSundell, in order to use the ndbmtd process rather than the ndbd process, does any alteration need to be made to any of the configuration files (e.g. /etc/systemd/system/ndb_mgmd.service)?
What is the appropriate reference/tutorial documentation for MySQL Cluster 8.0? Is it MySQL Cluster "MySQL NDB Cluster 8.0" on: https://downloads.mysql.com/docs/mysql-cluster-excerpt-8.0-en.pdf
Or is it "MySQL InnoDB Cluster" on: https://dev.mysql.com/doc/refman/8.0/en/mysql-innodb-cluster-introduction.html
Not sure I understand the difference.