It has been a hot minute since I shared my initial thoughts of the Asustor Drivestor 4 Pro Gen 2 (AS3304T V2).
To recap my from my first part to this review, the Asustor Drivestor 4 Pro Gen 2 (AS3304T V2) is a 4-bay, ARM-based NAS that supports Btrfs, multiple drive brands, and comes with a Realtek RTD1619B chip and fixed 2GB RAM. Setup is fast and beginner-friendly, with Asustor’s ADM OS offering a DSM-like UI and broad support for external devices. It accepts mixed-brand drives without complaint and features a single 2.5GbE port. However, the non-upgradable RAM could limit performance under load.
Part two of this review is going to be focus on the App Central offerings within ADM (Asustor Data Master). Fair warning, this is a more technical review.
tl;dr
App Central adds powerful flexibility to the Asustor Drivestor 4 Pro Gen 2, but its 2GB fixed RAM is a bottleneck for heavier apps. Great for tinkerers, limited for productivity-focused home users. Solid NAS core, but app ecosystem still maturing.
App Central
Like any good NAS OS, the base functionality of ADM can be extended with installation from App Central.
Think Google Play, Apple Store, Windows Store etc, the Asustor App Central is a central repository of curated applications that provides value-add to your NAS investment.
A rough count of the “All Apps” is around 160 in categories ranging from
- Business Applications
- Professional Design
- Backup & Sumc
- Security
- Media Server
- Ticket System
- Home Automation
just to name a few
I am not going to cover all of them. I went through the list and loaded up a few key ones for this review. These grabbed my attention but also, for reasons explained later, defined my thoughts on ADM as it is at this point in time.
RAM constraints
Going into this part of the review, I had some concerns over the amount of RAM that is baked into this Drivestor 4 Pro. It’s fixed at 2GB and no option to increase it. So let’s see what we can do.
Baselining the system, I turned off every application I installed for this part of the review. The one that I couldn’t stop, IronWolf Health Management, I uninstalled completely.
Then I rebooted the entire system and gave it about five minutes to settle after it came back online. This gives me the absolute bare minimum numbers of what the Drivestor 4 Pro requires just to be powered on.
Looking at the Activity Monitor screenshot:
- Memory utilisation sits at 20% (of 2 GB).
- CPU utilisation sits at 1%
Plex Media Server
A stalwart of self hosted media servers. I have been using it on one platform or another since around 2013. It has a native implementation on pretty much every platform, including here on ADM.
Firing up just the Plex Media Server process bumped the memory usage up by 5% to 25%, and stays there even when I am streaming a movie from it – in it’s native quality.
Forcing the system to transcode though, tells a different story.
- Memory utilisation increases to 34% (from 25%).
- CPU utilisation spikes up to 51% (from 1%)
There is a quite a significant delay before the system can stream the transcoded media.
Transcoding two concurrent streams pushed the CPU up another 10% to 61%.
It is not the end of the world, but you are starting to load up the CPU, with just one additional application running.
Photo Gallery 3
This is Asustor’s photo management system. Having played with it for a little bit of time, I found this one is a bit basic in functionality.
It functions largely as a photo repository with a display by timeline frontend, ability to manually create folders and albums. The system does auto generate a folder structure based on the date of the media.
You can also search for photos, but it’s not a contextual search.
For example you can’t search by say “apple” and get results of photos of apples, either the fruit or the product the company makes. The results are returned based on filename. This can be an issue which I will mention later.
Also of note is the limitation of 999 files per folder. So if you have thousands of photos to store on the Drivestor 4 Pro, then you will have lots of folders with 999 files in them.
From the PC I throw a bunch of decently sized files at it and they all uploaded fine via the browser interface. The CPU had a bump of about 7% during the process which is is no cause for concerns.
To upload from your mobile device, you will need to install the AiFoto 3 app from your app store. It is essentially a photo gallery replacement, with the option to backup to your Drivestor 4 Pro.
I am writing this part for the v3.3.2 of the Android app in particular.
In my testing I found the app to be very glitchy. I set the app to backup my DCIM (photo folder) which was the default option of the app. I also chose to backup my entire camera roll of 8700 media objects.
The upload breaks if you did not leave the app on screen, or if the screen lock engages. That is not ideal but the real dealbreaker is that it cannot resume when you go back into the app. Not even if you pause and resume the task.
[Updated 14 August 2025]
Asustor has pushed out some updates:
- ADM to 5.0.1.RKD2
- Photo Gallery 3 to 3.2.5.r747
- AiFoto 3 to 3.4.0
The upload issues I was experiencing earlier has gone away now. The app prompts you to permit “Run in Background” when you first set it up (I don’t recall seeing it in the earlier version but I could be wrong).
If you missed that setting early on, it is a little hidden to find afterwards. You need to tap on the picture next to Photos on the top left corner, then click on the cog on the top right corner. I have included screenshots below for reference.
Circling back to the search criteria, files uploaded from the mobile app will retain the generic filename. That will essentially limit your ability to find photos down to date and time.
Surveillance Center 3 (Beta)
The latest version of Surveillance Center on ADM is version 3, and is in beta mode. Notably it does not coexist with v2.8 due to port conflicts (and most likely other components).
I did actually try v2.8 for a bit. It is all kinds of horrible chunky UI straight out of yesteryear, so I opt to spend more time on the V3 beta. Out of the box ADM allows for four camera licence which is pretty nice.
For testing I have four Dahua cameras which are linked to a Surveillance Center on a different platform. During the review phase I changed my setup so that these cameras are dedicated to the ADM connections.
Baselining the system with other services disabled
- memory utilisation sits at 30% (of 2 GB).
- cpu utilisation sits at 3%
I would like to say that adding my Dahua to the ADM Surveillance Center was a breeze, it was anything but.
The wizard can perform a scan for all cameras on your network, and it picked up all four of my cameras successfully and quickly. That’s when the easy part stopped.
All my cameras were detected as ONVIF brand. Not strictly wrong as they are all ONVIF devices but I rolled with it, mainly because it does not allow me to change it on this screen. When I tried to add my credentials in, they all failed the verification.
Whereas when I manually add them as Dahua (regardless of model), two of the four cameras will come online – and this is with the same configuration I had with the auto detection.
The other two cameras I could successfully get a test image using a User-Defined Brand and both RTP and RTSP models.
So with a bit of fiddling around, I could get all my cameras added in Surveillance Center and tested to return an image.
Going into the Live View though, immediately shows “Server Disconnected” on the two User-Defined branded cameras.
The live stream on the two working Dahua camera streams is quite variable. One evening I have no issues with it coming up quickly. Another evening I was getting the spinning circle forever.
The resourcing does not seem to be an issue, with the CPU occasionally spiking briefly, and Memory is holding steady at 31%.
A nice feature buried in the advanced setting is the ability to set “pre-recording” for up to 30 seconds. This is particularly handy for cameras that does not natively have this feature.
However, other features such as privacy mask and watermarking does not appear to be available.
To be fair, the Surveillance Center 3 is a beta product, I feel there is still quite a way to go before it is ready. I certainly cannot migrate across from my existing host across to it as:
- It does not support all my cameras
- No privacy mask
- No watermarking of video stream
- Can be slow to get a live view
Home Assistant
Another application of interest is an ADM flavour of Home Assistant. I have talked about this piece of software in other reviews, and I am a huge fan of it.
Home Assistant is an open source home automation software that can bring together disparate ecosystems under the one umbrella, and allow you local control of your smart phone.
The benefits of the ADM version is that it is super simple to install, without needing to fiddle around with another device such as a Raspberry Pi or a NUC. I was very pleasantly surprised to find the package is fully up to date to the latest version – in line with my existing instance.
The downside is, the resource monitor is reporting 54% of the memory used on the Drivestor 4 Pro.
I won’t go into further details with configuring Home Assistant. It is not for the faint hearted.
AdGuard Home
For those sick of seeing targeted ads on everything, you can run AdGuard Home natively on ADM.
Essentially it becomes your local DNS server, and you can block ads and tracking system wide on the same network. It’s pretty magical, although there are just some stuff you can’t block like YouTube ads.
It also is something that needs a bit of tech knowledge to get going.
What happens if I run all of these applications?
Well, the CPU does pretty good when there is no load, such as no streaming of cameras going on. The memory sits around 53%.
I have only managed to stress the CPU when I am transcoding a video on Plex. Overall the memory usage is fairly stable once each application has started.
For a unit with just 2 Gb of RAM, I am actually impressed at what it can manage in terms of applications.
What are my thoughts?
I am a bit torn getting to this part of the review.
As a tinkerer, the ADM platform offers plenty. I have thrown the weirdest mix of drives possible at it and it has performed flawlessly. The basic NAS function is solid, and on par with my experience on other platforms.
The application support is heavily bias to people who wants to get their hands dirty – geared for self host enthusiasts, developers, IT geeks for wanting of a better description. Even when you read the frequently paltry descriptions in each app, it feels like there is an underlying assumption that you have a pretty good idea of what each thing does based on the name.
For your standard home user, who wants a simple device to store their files, back up their photos and the like, the platform feels like it is not quite mature enough.
Yes there is Photo Gallery, but the Android version of the app was pretty glitchy.
There is no productivity offering such as a replacement for a word processing or spreadsheet application. Yes there are free cloud alternatives, but those will take the file storage away from the Drivestor 4 Pro Gen 2.
Further, this is driven by a personal requirement I had recently, this particular model the Drivestor 4 Pro Gen 2 (AS3304T V2) lacks the memory to run virtual machines. During a recent work trip, I wanted to spin up a virtual machine for a specific task I need for DRN but this chassis was not capable of it.
Final Verdict
I feel the Asustor offerings are worth considering for two types of users:
- tinkerers who want a platform with good developer support
- home users not needing productivity tools
The reasons are the same – the Asustor offerings come without brand restrictions on drives, and also come with USB ports that support sharing of devices such as external drive and printers.
My review chassis, the Asustor Drivestor 4 Pro Gen 2 (AS3304T V2), is RAM constraint to 2GB which really is insufficient to take full advantage of ADM’s strengths. However, there are other models available in the series that will take care of that issue.
Overall I think the App Central part of the Asustor NAS devices still need time to mature to be competitive. The core of the NAS provides a solid platform for Asustor to build on.
As it stands though, Asustor is not on the private cloud boat. It is kind of doable with the right technical knowledge, but it is not end user friendly. It is in a space where NAS was still mainly just data storage, before it became an enabler for private cloud.
DRN would like to thank Asustor for providing the review unit.
