The local system is MacOS. The installation system is CentOS; The VIRTUAL machine product used is Parallels Desktop.

According to the procedures in the installation manual:

  • Digital signature verification;
  • Query system information.
  • Create an installation user.
  • Check system limits;
  • Check the system memory and storage space.
  • Disable firewalls and selinux policies;

Digital signature verification

Skip this step because of the downloaded trial version.

Querying System Information

Reason for querying system information: Check whether DM8 can be installed on this machine. I don’t know for the time being, except for the basic requirements, which machines can’t be installed with DM8.

The query method is as follows:getconf LONG_BIT: Queries the system bits:

lsb_release -a: Queries the release information of the operating system. The command cannot be found for the first time, and the system prompts you to install itredhat-lsb-coreThis package can be used after the installation is complete.

cat /etc/issue: Queries system information.

uname -a: Queries the system name.

Creating an Installation User

The reason for creating an installation user: Do not use the root user to install and run the DM to avoid adverse impact on the operating system.

To create a user:

  1. Create an installation user group:dminstall
groupadd -g 12349 dminstall
Copy the code

Check whether the installation is successful:

cat /etc/group
Copy the code

Generally successful installation will appear in the last item

  1. Creating an Installation Userdmdba
useradd -u 12345 -g dminstall -m -d /home/dmdba -s /bin/bash dmdba
Copy the code

Run the following command to check whether the vm is successfully created:

cat /etc/shadow
Copy the code

It will appear in the last item if created successfully

  1. Initialize user password:
passwd dmdba
Copy the code
  1. Log out and then log in as dMDba.

Check operating system restrictions

Reason: On Linux, the use of operating system resources may be limited by the presence of ulimit.

useulimit -aQuery all parameters:

Change the resource limit of ulimit

  1. ulimit -n 65536: Changes the maximum number of open files to 65536. This change takes effect only for this session. The modification options are listed below.
  2. Modify the configuration file. The file address is:/etc/security/limits.conf.

Add to this file:

dmdba soft nofile 65536
dmdba hard nofile 65536
Copy the code

Check the system memory and storage space

Checking system Memory

At least 1GB of available memory is required to ensure the DM is running properly. If the memory is too small, the DM may fail to be installed or run.

  • Get total memory size:grep MemTotal /proc/meminfo

  • Get swap partition size:grep SwapTotal /proc/meminfo

  • Get memory usage:free

Checking Storage Space

To query the available space, run the df -h /dirname command

  1. DM8 requires 1GB of storage for a full installation. Reserve usable space for the database instance as well.
  2. DM8 generates 1GB of temporary files when installed. Temporary files need 1GB and the default address is in/TMP. You can do this by setting environment variablesDM_INSTALL_TMPDIRSpecifies the temporary directory for the installer.

Disabling firewalls and Selinux policies (critical)

A firewall

  • Check firewall status:systemctl status firewalld
  • Stop the firewall:systemctl stop firewalld
  • Disabling a firewall:systemctl disable firewalld

Close the selinux

Check whether selinux is disabled:getenforce vim /etc/selinux/configInstead ofSELINUX=disabled

Dameng community website: eco.dameng.com/