Configure an OBServer node to start automatically on boot

This topic describes how to configure an OBServer node to start automatically on boot through online settings or offline settings depending on whether the OBServer node can access the Internet.

Scenarios

The configuration methods described in this topic are applicable only if the following requirements are met:

• An OceanBase cluster is deployed and not managed by OceanBase Shell (OBShell).

• You are using OceanBase Database V4.2.1.4 or later.

Online settings

If an OBServer node can access Internet, you can log on to the OBServer node and run the following command:

[admin@test001 ~]$ sudo bash -c "$(curl -s https://obbusiness-private.oss-cn-shanghai.aliyuncs.com/download-center/opensource/obshell/service_installer.sh)"

Offline settings

If an OBServer node cannot access the Internet, you can log on to the OBServer node and perform the following operations:

1. Create a script file.

   In this example, the file is named self_start.sh. You can use a custom name as needed.

   [admin@test001 ~]$ vim self_start.sh
   

   The content of the script file is as follows:

   #!/bin/bash
   
   # Prompt the user for input and retrieve it
   prompt_for_input() {
       local prompt_message="$1"
       local user_input
       read -p "$prompt_message" user_input
       echo "$user_input"
   }
   
   # Check if the homepath argument was provided via the command line
   expected_arg_name="homepath"
   if [ $# -gt 0 ]; then
       arg_value="$1"
   else
       # No arguments provided, ask the user for the homepath
       arg_value=$(prompt_for_input "Please enter the $expected_arg_name: ")
   fi
   echo "Using $expected_arg_name: $arg_value"
   
   # Check for the existence of the 'obshell' file in the provided homepath
   homepath=$arg_value
   obshell="$homepath/bin/obshell"
   if [ ! -f "$obshell" ]; then
       echo -e "\033[31m[ERROR]\033[0m Sorry, [$obshell] does not exist."
       echo "You may need to upgrade the obcluster. Please consult the developers for assistance."
       exit 1
   else
       echo "[$obshell] has been found in the work directory."
   fi
   
   # Check if the oceanbase.service file exists
   system_dir="/etc/systemd/system"
   oceanbase=$system_dir/oceanbase.service
   # Check if the service file exists
   if [ -f "$oceanbase" ]; then
       echo -e "\033[33m[WARN]\033[0m oceanbase.service has beed installed."
       echo "Please use 'systemctl status oceanbase.service' to check it."
       exit 0
   else
       echo "Service file $oceanbase does not exist."
   fi
   
   # Retrieve the owner of the 'observer' process configuration files
   owner=$(stat -c '%U' $homepath/etc)
   echo "Owner of the observer configuration: $owner"
   
   # Construct and output the content for the systemd service unit file
   name=observer.service
   mkdir -p $homepath/tmp
   file=$homepath/tmp/$name
   echo "Creating the service unit file at $file..."
   # Write the service content to the file
   cat << EOF > ${file}
   [Unit]
   Description=observer
   After=network.target
   [Service]
   User=${owner}
   Type=forking
   KillSignal=SIGKILL
   ExecStartPre=${homepath}/bin/obshell admin stop
   ExecStart=${homepath}/bin/obshell admin start --takeover 0
   ExecStartPost=${homepath}/bin/obshell admin stop
   ExecStop=${homepath}/bin/obshell admin stop
   PIDFile=${homepath}/run/observer.pid
   Restart=no
   SuccessExitStatus=SIGKILL
   [Install]
   WantedBy=multi-user.target
   EOF
   echo "The content of the Service unit file is:"
   sed 's/^/  /' "$file"
   
   # Deploy the unit configuration file to the system directory
   echo "Deploying the service unit file to the system directory"
   cp -f $file $system_dir/$name
   echo "Updating permissions for the service unit file..."
   chmod 644 $system_dir/$name
   echo "Reloading the systemd daemon to recognize the new service"
   systemctl daemon-reload
   systemctl enable observer.service
   echo -e "\033[32m[SUCCEED]\033[0m observer.service has been installed."
   

2. Run the script file.

   In this example, /home/admin/oceanbase is the installation directory of the OceanBase cluster. Specify the actual directory when you run the script file.

   [admin@test001 ~]$ sudo sh self_start.sh /home/admin/oceanbase