In this issue we are going to discuss relay servers; what are they, what do they do, and why do I need them, and how do I use them?
Let’s start with what a relay server really is. In the most basic sense a relay server any system with an agent that passes on communications from other agents. These can be any device with an agent installed, the only difference from other devices is one change in their configuration that flags them as a relay. In most cases this will still be a server of some level, but just as well could be an always on workstation depending on the situation. You can set the configuration option to make a device a relay in the rollout you use to install them, manually through the asset core console or configuration files, or using an operational rule. We’ll go over all that in more detail later.
Alright, so that sounds good and all, but what do they actually do? As mentioned earlier, relays pass data from one machine to another. Every device in Asset Core has a parent, they send their data to this device and only accept data from it. This changes when you make the device a relay. Once set to be a relay the device will accept connections from any device that is configured to use it as a parent. It then takes this data and passes it up to its parent on up the chain. When sending data back down to a client that data is first sent to relay and then from the relay back to the device.
Sounds great so far, but why would I want to use them? Since relays act as a single point for multiple child devices below them, but only connect to one parent device above them, they can be used to better manage the way data crosses the network. As an example of why this is a good thing, think of a network with 1 main office and several satellite offices connected across WAN links. In the main office all the devices are on a fast network and there isn’t much concern having them talk to the Asset Core master server. The problem comes in with the remote sites. Since every bit of bandwidth matters you don’t want each computer at the remote site to transfer everything across the WAN. To prevent this you put a relay server in each office, these devices now talk on the local LAN to the relay and only that one relay talks across the WAN. This means the relay will gather all the data and send it upstream and downstream. Since things only have to be transmitted once it means less bandwidth usage. If you need to send a large package to all the devices at the remote site, it only has to be sent once. The relay stores the data from its parent and then sends from there to its child devices.
Ok, since it saves me bandwidth and makes the communications flow smoother, how do I set up a relay? First thing is to get the device flagged as a relay. This can be done in several ways, the first is to build a rollout that is used just to install on relays. This is done by building a rollout as normal in the Rollout Wizard, but on the first step, “Core Setup Configuration”, check the option for “Enable agent as a relay for other agents”. That’s it, you then just finish the configuration as you normally use.
The next way you can make a device a relay is through the console. To do this, find the device and expand it on the left and side. Expand Agent Configuration (you may be prompted to enter a windows account to access the system). Expand Module Configuration and Select Relay. On the right hand pane Right Click and go to properties. Check mark “Is Enabled” and click ok. You’re done! The device is a relay.
The last 2 ways are to create an operational rule to modify the relay module settings or by manually editing a configuration file. If you are interested in taking this method please contact Technical Support as this could cause unintended configuration changes.
Once your relays are configured your devices need to be setup to point to the relays. Normally this is done during the initial rollout, but can also be done after the fact. This is an in depth topic as there are many ways to configure this. Some of the methods allow the devices to search a list of relays, which is good for when a device moves from office to office, others are statically set. As there are many ways this can be setup we urge you read the full documentation, contact Technical Support, or discuss you’re your Professional Services technician before you begin the setup. You can find the full documentation on rollout and relay configuration in the full document files which are available for download on your support profile at http://support.numarasoftware.com
We hope you have found this information helpful. If you have any questions or comments please leave them below or contact us here at BMC. Have a great day, we look forward to seeing you next time!