Installing the Data Service

Before you begin

Log in to the host (repeat this procedure for every data host):

# ssh root@server_ip_address

Note: You must log in as a privileged user. This example uses the root login. If you use a non-root login, you might need to run the installation commands using sudo.

Configure the Direct Access (

DAX

) devices containing the persistent memory for the host you are installing. See Preparing Intel Optane DC PMEM.

Install the following dependencies required by Memory Machine.

Important: Installing these dependencies is required only if you are installing on CentOS 7. They are shipped with RHEL and CentOS 8.

# yum install libnet protobuf-c

About this task

Use this procedure to install Memory Machine data services to a single host. To install only the management service on a host, respond "No" when asked if you want to install data services.

Procedure

Set the max_map_count parameter. MemVerge recommends setting max_map_count to 6.3 million. This is a sufficiently large value to accommodate any existing DAX device setup.
1. Optional: Check the current max_map_count setting:
```
# sysctl -e -q vm.max_map_count
vm.max_map_count = 65530
```
2. To change max_map_count to 6,300,000 in the current scope:
```
# sysctl -w vm.max_map_count=6300000
vm.max_map_count = 6300000
```
3. To make this setting permanent (so that it persist across reboots), update the vm.max_map_count parameter in /etc/sysctl.conf:
```
vm.max_map_count=6300000
```
Copy the Memory Machine Package File, MemoryMachine-release-OS.bin, to a directory on the host. In the following example, the file is copied to the root home directory, /root:
```
# scp root@b:/path/to/MemoryMachine-v1.1.0-rhel7.bin /root
```
The Memory Machine Package File is a self-extracting package that unpacks files to the host and begins running the installation script. Run the package file as a privileged user:
```
# MemoryMachine-release-OS.bin
```
where:

release

is the Memory Machine software release number.

OS

represents the Linux operating system for which the software is compiled.

The following extended example shows a typical install. Once you type the install command (./MemoryMachine-v1.1.0-rhel8.bin in the example), the script runs as one long session. Comments intererspersed below explain the required responses.
```
# ./MemoryMachine-v1.1.0-rhel8.bin
Verifying archive integrity... All good.
Uncompressing MemVerge Memory Machine  100%
Welcome to the MemVerge Memory Machine installation wizard!
Please press ENTER to read the MemVerge End User License Agreement:
I have read and agree to the End User License Agreement [y/N]: y
```
After acknowledging the license agreement, you are prompted to install the data service. Choose "no" if you are installing this host as the management center but not as a data host. See Installing the Management Service.
```
Do you want to install data services? [y/N]: y
Start installing the Memory Machine data service? [y/N] y
```
If you continue with the data service installation, the script prompts you for an installation path. Press enter to use the default path, /opt/memverge.
```
Type the installation path. (Press enter to use the default path: /opt/memverge):
--> Performing pre-installation checks...
```
Memory Machine gives you the option of changing from its default socket path during installation. If you don't use the default, you must provide an existing writeable socket path as an alternative.
```
Type the socket path. (Press enter to use the default socket path: /tmp/dpme_daemon.0):
--> Installing binaries...
--> Installing libraries...
--> Installing configuration files...
--> Installing mvmallocd system service...
--> Installing mvcsnapd system service...
--> Installing mvmlog_groom cron service...
--> Creating mvmm user id and user group...
--> Changing ownership to mvmm...
/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/opt/q:/root/bin:/opt/memverge/sbin
```
The script next prompts for a data directory in which to store snapshot-related data. MemVerge recommends that you either accept the default directory on the current server or provide a high-availability network directory. If this directory becomes unavailable, snapshots cannot be captured or restored.

The Memory Machine log directory is installed at /var/log/memverge. You cannot change this location.
```
Type the path of the snapshot directory.
(Press enter to use the default path: /var/memverge/data):
The directory /var/memverge/data does not exist. Create this new directory? [y/N] y
Directory /var/memverge/data has been created.
Created log directory /var/log/memverge.
Done.
```
Continue by selecting which DAX devices you want to manage with Memory Machine:
```
Select the DAX device(s) to use:
1. /dev/dax1.0 size:63.00GiB
2. /dev/dax0.0 size:63.00GiB
Please choose one or more items, separated by "," (for example: 1,3): 1,2
Selected DAX device(s):
/dev/dax1.0
/dev/dax0.0
```
The script installs and starts the Memory Machine Agent service. The agent service must be run on all data hosts.
```
Installing the mmagent service...
Done.

Starting the mmagent service...
mmagent service started.
```
You are prompted to install the management center. You can install a standalone management host (skipping the data center installation above), or run the management center concurrently on a data host.

If you have chosen to install only the data service on this host, choose "No" at the management center prompt to end the script.
```
Do you want to install management center? [y/N]: 
```
If you choose not to install the management center, then the script prints instructions for some post-installation tasks:
```
To launch the Memory Machine data service (requires root):
1. Start the mvmallocd and mvsnapd system service:
      systemctl start mvmallocd.service mvsnapd.service
2. Make the data service start automatically when the system starts (optional):
      systemctl enable mvmallocd.service mvsnapd.service
To allow an existing user to use Memory Machine:
      usermod -a -G mvmm user-id
Re-login is recommended for the user-id to enable its mvmm group membership.
#
```

What to do next

To install the management service on this host, choose "yes" to the management center prompt and continue with Installing the Management Service.

If you plan to install the management service on a different host, choose "No" to the management center prompt. You can then continue configuration of this host by going to Initializing Direct Access Devices.