Installation and Upgrade (Linux)
SmarterMail High Availability, or SmarterMail HA for short, allows businesses to build a fault-tolerant SmarterMail cluster on the exact same code base as previous versions of SmarterMail. It has 2 different installation files, one for hubs and another for nodes.
Jump to:
- Prerequisites
- Share Setup
- Hub Installation
- Node Installation
- Upgrading SmarterMail HA
- Things to Know
- Welcome to SmarterMail
Prerequisites
Prior to installing SmarterMail HA, you’ll need to have these things configured:
- You’ll need 1 Windows or Linux server or VM that will be used for storing domain and user settings. You will also need a shared folder with concurrent read/write access for a domain or local user. NOTE: SAN or NAS storage can also be used.
- You will need a Linux server or VM for your Hub. (Multiple hubs can be set up for redundancy, but will need at least one to get started.)
- You will need a Linux server or VM for at least one Node. (Multiple Nodes can be set up for redundancy, but you will need at least one to get started.)
- You’ll need to have both the hub installer script and the base installation script for your node(s). These are available from the SmarterMail Downloads page.
Share Setup
As SmarterMail HA is a clustering solution, emphasizing redundancy and fault tolerance, centralized storage is really a requirement. This can be handled us NFS or Samba shares on Linux, folder shares on Windows, or even using a SAN or NAS. Regardless of what is used, the following will be required so that SmarterMail HA hubs and nodes have access to this shared storage.
- Create a network shared directory on your Windows or Linux server, SAN or NAS. NFS or Samba shares work for Linux.
- Inside this shared directory, you will want to create a folder for your hub(s) and well as folders for each of your nodes. For example, your folder setup can look like this, where “data” is the shared directory:
- /data/hub - folder that will be used by each of your hubs
- /data/node1 - folder for your first node
- /data/node2 - folder for your second node
- /data/nodeN - additional folders for any additional nodes
- Mount the share created for your hub (e.g., /data/hub/) on the hub server or VM. (NOTE: You do not need to mount shares on your nodes, though you can. If you choose not to, you can add mount/unmount commands for your shares when you walk through Node Configuration.)
Hub Installation
Run the following in bash command to download and run the SmarterMail hub installer. Replace the XXXX with the build number you wish to install:
&& chmod +x smartermail_hub_XXXX \
&& sudo ./smartermail_hub_XXXX install
The installation includes setting up all folders and directories needed to run a SmarterMail hub.
Node Installation
Installing your node is no different than installing a standalone SmarterMail server. Run the following in bash command to download and run the SmarterMail installer. Replace the XXXX with the build number you wish to install:
&& chmod +x smartermail_XXXX \
&& sudo ./smartermail_XXXX install
The installation includes setting up all folders and directories needed to run a SmarterMail hub. You can repeat the above for any additional nodes you will be using in your SmarterMail HA cluster.
Upgrading SmarterMail HA
To upgrade SmarterMail, first, backup your SmarterMail installation or take a snapshot of your VM.
When upgrading hubs and nodes, it’s important to note that all hubs and nodes should be upgraded to the same version, and that there is an order of operations when it comes to upgrading. This ensures that the upgrade process is smooth and that impact for users is kept to a minimum, and that the hubs are up and running before the nodes attempt to connect.
The order is as follows:
- Stop all nodes.
sudo service smartermail stop
- Stop all hubs.
sudo service smartermail.hub stop
- Upgrade both hubs and nodes.
- Start the hubs.
sudo service smartermail.hub start
- Start the nodes.
sudo service smartermail start
As for the upgrade process itself, it’s pretty simple. With the services stopped, run through the Hub Installation and Node Installation sections, replacing the Build numbers with the most recent Build of each. Remember: hub installations will have “_hub” in the build number, nodes will not.
Things to Know
- The Release Notes for all major and minor versions of SmarterMail, as well as Release Notes for all current Builds, are available on the SmarterMail Release Notes page of our website. It's a great idea to familiarize yourself with all the changes that have been made to SmarterMail between the version you're on and the version you'll BE on once you've upgraded.
- As SmarterMail HA has a monthly License Agreement, all hub and node licenses work like lease licenses: that is, they will always be valid for any new version of SmarterMail that's been released. In addition, HA licenses are retroactive to previous versions of SmarterMail.
Set Up and Configuration of Hubs and Nodes
After SmarterMail is installed, it's time to set up and configure your hubs, and then setting up nodes and associating them to the hub.
SmarterMail HA DNS Notes
Each node, each hub, any load balancer, and any gateways should have a unique A record configured in DNS. Additionally, each server in your cluster should have a valid PTR record configured that points back to that A record.
If your nodes exist on internal IPs only, the externally facing IP (that traffic will come from when sent from those servers) should have proper A record and PTR records set so that mail servers will not block the traffic as invalid.