As part of an article series dedicated to the Synology NAS solutions this one focuses on the configuration of the Synology DS620Slim Storage Pool. The Storage Pool is essentially a logical group of disks part of the same configuration. This constitutes the base for next logical constructs like Volumes and LUNs built on top of the Storage Pools. Ultimately the LUNs are the physical storage where VMware vSphere Hypervisor and other operating systems in general access to create and allocate the required storage. For example a VMware Datastore or Physical Storage to create disk volumes for operating systems. Everything is software defined. Means adding, removing or replacing disks when required it is a very simple process. For example to increase capacity or simply put to replace old failing drives. The Storage Pool takes care of these aspects and when configured correctly provides a transparent approach to storage facing applications and operating systems. The purpose of this article is to cover the steps for the Synology DS620Slim Storage Pool configuration and provide LUNs to create several VMware Datastores.
Synology DS620Slim storage Pools
The steps to configure the Synology DS620Slim Storage Pools are pretty simple and most of all wizard driven. Which means the entire setup is just a matter of few clicks on the next screen. As expected it is possible to start the Storage Manager from the Control Panel or even quicker choosing the link from the start menu > Storage Manager > Storage Pools. Before proceeding it is advised to update the NAS device to the latest firmware. Again also in this case the process is wizard driven and very easy to follow.
This example covers only SSD Disks as part of the Storage Pool. Due to the cheaper costs, it might make sense to invest on these rather than traditional SATA drives. Should SATA disks be available or even desired it is possible to configure an SSD cache location as a “performance tier” for faster access of frequent data. When the Storage Pool is already running on SSD storage then the SSD cache will be disabled. Next step is to click on Create to initiate the Storage Pool group.
Assuming the DS620Slim Storage Pool will serve multiple volumes the second option about Higher Flexibility is the best one. For this particular case only one Volume will be created. Such Volume will host the different LUNs that will be presented to the VMware vSphere infrastructure. In this case the first option “Better Performance” is the best suited.
In the next screen is possible to choose the RAID type the DS620Slim Storage system will use to create and manage the stripes across different physical disks. Based on the actual number of installed and recognized drives only the suitable RAID types will be available on drop down menu. Considering the number of actual installed drives (3) and the workload type where there will be more Reads rather than Writes, the RAID 5 offers a good compromise in terms of fault tolerance and performance. Of course protecting data with Backup brings that peace of mind when either single Disks or the entire RAID are not recoverable.
Next step is to select the installed drives which will be part of the Storage Pool. As per screenshot below the 3rd disk is on position 6 (bay number). The DS620Slim supports hot swap drives.
In the next screen it is just a matter of accepting and let the NAS start erasing the content of the drives. Operation is not reversible so it is important to select and use the correct drives!
At this point the DS620Slim Storage system has the information to create a disk pool formatted with RAID 5 for data redundancy. It also shows the total capacity. With 3 disks in RAID 5, 1 TB each, one disk is always used for data parity totalling 2 TB. Of course this type of RAID can support up to one disk failure. The great news is the DS620Slim provides up to 6 Bays. This means other RAID types can be used. Should the recovery from failure of multiple disks at the same time is required.
As soon as the settings are confirmed the DS620Slim Storage creates the format the Storage Pool. This operation will carry on in the background while it is still possible to run other apps. Depending on the installed RAM Memory and the total drives capacity this operation might complete faster. In any case the DS620Slim also allows to add extra RAM Memory. Officially it supports up to 6 GB Memory and is also possible to add RAM slots with higher capacity.
Visiting the Storage Manager > Storage Pool section it shows the current progress.
The configuration for the DS620Slim Storage Pool is a very simple and straight forward process. Allows to even create and manage an SSD cache tier when the a mix of both SATA and SSD disks are used. This option is naturally disabled when using SSD drives. Considering the latest technology trends, cost and performance it makes sense to invest in the latest format. The entire process is wizard driven and allows replacing the drives very easily (assuming drive failures) and adding new ones to increase capacity. The selected RAID type will format and extend the pool in order to accommodate the new data stripes. The Storage Pools allow for extra configurations like Data Scrubbing and RAID ReSync speed limits which will be covered in dedicated articles.