I’m currently working on designing a customized IO board for the CM4 for this exact purpose. We decided on 1 terabyte of storage, meaning two 1TB external drives. SATA random IO speeds are way faster, so if you're using the Pi to serve up disk images for netboot, VMs, or even for small file sharing, it's going to be a lot faster even over a 1 Gbps port than the same drive through USB 3.0. But a 5 port compact SATA SSD NAS would also be interesting. Set this up and create a regular cron job to make sure your data survives. No keyboard, mouse or display are required to be connected to the Pi. Happy birthday Make an online birthday card on a webpage. Assemble And Format The Disks. As with most Pi projects, youâll want to open a Terminal, either on the Pi itself â¦ Here are links (Amazon affiliate links—gotta pay the bills somehow!) Give the system a few seconds to âseeâ the disks, then enter the following: This command tells you about devices connected to the system. Win one of five of the latest version of Raspberry Pi! If the second drive fails, disaster. Youâll save money and get a regular supply of in-depth reviews, features, guides and other PC enthusiast goodness delivered directly to your door every month. these. Using iSCSI (as opposed to NFS or SMB) can be much more efficient. Come with us and celebrate with this special edition of The MagPi magazine. Now, thanks to the improved throughput of Raspberry Pi 4 with USB 3.0 and Gigabit Ethernet, you can build a fully featured NAS for a fraction ofÂ theÂ cost. over 1 year ago. Unfortunately, after the upgrade, I discovered that iperf benchmark had very little to do with the actual practical performance. The RAID-1 system is operational. But the HDDs on the label had the same minimal power requirement, so I don't see why the 12V/2A supply wouldn't work for them. The first card I tested after completing my initial review was the IO Crest 4-port SATA card pictured with my homegrown Pi NAS setup below: But it's been a long time testing, as I wanted to get a feel for how the Raspberry Pi handled a variety of storage situations, including single hard drives and SSD and RAID arrays built with mdadm. There was a post here that provided some basic instructions for setting up OMV5 on buster. Visit our projects site for tons of fun, step-by-step project guides with Raspberry Pi HTML/CSS Python Scratch Blender. The one starting âmmcblk0â is the microSD card containing Raspbian. to all the different products I used to build my SATA RAID array: Wow. In reply to Hi thank you for sharing… by Johan. All content copyright Jeff Geerling. Is enough with the same power supply? Amazing work! One thing you must have mentioned that a backup power, the files will be doomed if such thing happens. Since I have three disks, Iâll be using RAID 5 because it offers redundancy and more storage available than RAID 1. Today I'll show you how to build a rock-solid home/office NAS server using a Mini-ITX motherboard, a dedicated hardware RAID card, and enterprise class SAS hard drives, all in a Mini-ITX NAS case with an 8 drive hot-swap bay. Finally, make sure everything is up-to-date with sudo apt update && sudo apt -y upgrade, then reboot. (It's single client, so synchronization primitives are less important. Now type âwâ (to write the changes to the disk). Posted In reply to No link for the RPI4? However, setting it up as one used to be an involved process. And the SATA kernel modules are not included by default, which means the first step in using a PCIe card like the IO Crest (which has a Marvell 9215 chip—which is supported in the kernel) is to compile (or cross-compile, in my case) the kernel with CONFIG_ATA and CONFIG_SATA_AHCI enabled. Samba is a re-implementation of the SMB (Server Message Block) networking protocol that allows Linux computers to seamlessly integrate into active directory environments. These file- and media-serving black boxes can punch a hole in your bankÂ account, particularly the professional versions aimed at businesses. Disappointed with the results I accepted the failure and moved to other projects. The first card I tested after completing my initial review was the IO Crest 4-port SATA card pictured with my homegrown Pi NAS setup below: But it's been a long time testing, as I wanted to get a feel for how the Raspberry Pi handled a variety of storage situations, including single hard drives and SSD and RAID arrays built with mdadm. Besides this GitHub issue, I documented everything I learned in the video embedded below: The rest of this blog post will go through some of the details for setup, but I don't have the space in this post to compile all my learnings here—check out the linked issue and video for that! Obviously, it's not an option when you need to share files — you need to unmount it from one client and mount it on another. The design of Raspberry Pi means using external USB disks. Technically it's not required to partition before creating the array... but there are a couple small reasons it seems safer that way. (If you get an error that a partition already exists, use âdâ to delete it â this will lose any data on the disk!) To do this we use fdisk. But putting slower hard drives into RAID can give better performance, so I next tested all four WD Green drives in RAID 0 and RAID 10: And, as you'd expect, RAID 0 basically pools all the drives' performance metrics together, to make for an array that finally competes with the tiny microSD card for 4K performance, while also besting the Kingston SSD for synchronous file copies. 2 Ã External USB drives (minimum), e.g. By Lucy Hattersley, Build a Home Assistant: the light fantastic, Play with colour and mood, or go completely disco with Home Assistant's light controls. We will use that as a basis to for the installation. If you have more drives, it will continue up the alphabet. I appreciate you a lot for doing this. In this project, weâre going to setup a Raspberry Pi 4 NAS using openmediavault. Also, for now I don't use a power switch (though later on I might wire one up), nor do I have any kind of indicators (yet). Raspberry Pi-powered quad NAS with Radxa SATA HAT Radxa has announced the ROCK Pi SATA HAT, a series of SATA expansion targeting at the NAS solution for Raspberry Pi 4 and ROCK Pi 4. Rock band Make your own musical instruments with code blocks. â Characteristics of Linux RAID levels â Build your own Raspberry Pi NAS â How to Setup a Raspberry Pi Samba Server â Build a Raspberry Pi RAID NAS Server â Complete DIY Guide â Partitioning, Formatting, and Mounting a Hard Drive in Linux Then enter âpâ (for primary partition). Replace the failed disk as soon as possible and the array is ârebuiltâ. In reply to How much ram does the… by oREDi. For a much more affordable way to store loads of files to share with friends or family, Raspberry Pi 4 is ideal. Rotary drives give us lower cost and higher capacity than SSDs. There are many different forms, but weâre using one of the simplest: RAIDâ1, or mirroring. So more RAM would definitely help make for more consistent transfers, but I don't think that's the only bottleneck, as copies would still start showing slowdowns after only 1-2 GB sometimes, even after a fresh reboot. Also, the client OS can do more caching.) For each of the drives that were recognized, if you want to use it in a RAID array (which I do), you should add a partition. Or it's power supply? For the more adventurous user, Docker is an excellent way of making your NAS perform multiple functions without getting into a configuration nightmare. I work with storages for last ten years, maybe more, but what you do here is just excellent :). Today we will be looking at how to build your very own Cloud software system that will allow you to store your personal information in a cloud that you Control and maintain. You can find a few SATA HATs for the Raspberry Pi 4 that support single SATA or mSATA connections, such as Geekwormâs $26 X825 or Renkforceâs $19 SATA Extension Board, but Radxaâs new line of SATA HATs for network attached storage (NAS) applications appear to be the first to support multiple SATA connections. change password and display IP address. Using Samba is one of the simplest ways to build a Raspberry Pi NAS as it is easy to set up and configure. I also wanted to measure thermal performance and energy efficiency, since the end goal is to build a compact Raspberry-Pi based NAS that is competitive with any other budget NAS on the market. This one is the 4GB version, and running free -h during the benchmarking shows the Pi is filling up its RAM with filesystem cache data. If a drive does fail, your system will be in a âdegradedâ state, meaning that data is at risk until the drive is replaced. If you wish, configure WiFi at this point, but for a decent NAS youâll ideally be using the lovely full-speed Gigabit Ethernet port. RAID 10 backs off that performance a bit, but it's still respectable and offers a marked improvement over a single drive. We imaginatively changed ours to ânasâ, so the network address is ânas.localâ. This partâs pretty easy. Extract the disk image. In some of my testing, I noticed what looked like queueing of network packets as the Pi had to move network traffic to the RAID array disks, and I'm guessing the Pi's SoC is just not built to pump through hundreds of MB of traffic indefinitely. Getting access to those files and making sure they are protected from drive failure can be challenging without an expensive network-attached storage (NAS) solution. Many UPSes can communicate their status to your Raspberry Pi over USB, so a safe shutdown can be triggered. Alternatively, you can create additional entries in smb.conf for multiple shares. To provide a layer of protection, youâll need to double the number of drives to make sure your data is safer. At this point in time, the software being used is beta â openmediavault 5. I covered that in the video here: https://youtu.be/oWev1THtA04?t=1096 — but basically it uses ~6W at idle (with drives on), and ~12W max under highest load writing files over the network. Using Linux's Multiple Device admin tool (mdadm), we can put these drives together in any common RAID arrangement. By Rob Zwetsloot. maltesander In this tutorial we build a NAS Samba DLNA RAID server on RaspberryPi 3 Model B. To keep things fair, since it couldn't hold a candle to even a cheap SSD like the Kingston, I benchmarked it against my favorite microSD card for the Pi, the Samsung EVO+: While the hard drive does put through decent synchronous numbers (it has more bandwidth available over PCIe than the microSD card gets), it gets obliterated by the itsy-bitsy microSD card on random IO! I upgraded my Raspberry Pi 2 NAS to the latest and greatest Raspberry Pi 3B+ hoping to get the network performance boost promised by an excellent iperf benchmark. The â¦ So, to grant access to the current user, âpiâ: Youâll be asked to choose a password (it doesnât have to be the same as your Raspberry Pi password). This cloud will also employ a RAID â¦ Rob is amazing. That means it should protect against system failures that cause significant downtime, and make sure no data is lost as a result of those failures. To use a Pi 1 or 2 â¦ I am not so experienced with pi, but why didn't you consider OMV ? Youâll be asked a series of questions about sectors. The Raspberry Pi, on the other hand, is such a versatile little board that it can act as a cheap trial NAS thatâonce you grow out of itâcan be repurposed for something else. For reliable power we added a powered USB 3.0 hub. Now to share some files on the network using the popular protocol, SMB/CIFS. Try three issues for just Â£5, then pay Â£25 every six issues. Should a disk fail, your NAS keeps running and you donât lose anything. Finally, change your password and, under Network Options, change the Hostname (the NASâs network name) if you wish. The most important decision youâll make is how much storage youâll need. A Raspberry Pi NAS is affordable and easy to set up, all you need is a Raspberry Pi and some digital storage. To make sure mdadm automatically configures the RAID array on boot, persist the configuration into the /etc/mdadm/mdadm.conf file: And to make sure the filesystem is mounted at boot, add the following line to the bottom of your /etc/fstab file: One other thing I had to do a number of times during my testing was delete and re-create the array, which is not too difficult: Then also make sure to remove any entries added to your /etc/fstab or /etc/mdadm/mdadm.conf files, since those would cause failures during startup! Building the fastest Raspberry Pi NAS, with SATA RAID, recompiling the kernel with SATA support on the Pi itself, Samba and NFS installation guides in this issue, CableCreation low-profile SATA cable 5-pack, CoolerGuys 12v 2A Molex power adapter (for drives), Cable Matters Molex to SATA power adapter, ICY DOCK ExpressCage 4-bay 2.5" hot-swap cage, Cross-compiling the Raspberry Pi OS Linux kernel on macOS, I'm booting my Raspberry Pi 4 from a USB SSD, You can use a PCIe switch and use both the SATA array. Self-storage. You need to repeat the process for the second drive by entering: RAID (redundant array of inexpensive disks) is a method for protecting data by duplicating it over multiple disks. Very thorough job. It canât compete with Intel-based systems in terms of speed or features, but if you have some external USB disks lying around, itâs a very affordable way to not only serve your data, but protect it as well. Tutorials on Linux, Raspberry Pi, Windows and Networking. The limiting factor in the performance for a NAS on RPI is always going to be the 1GB Ethernet port. I'm looking for a new project and this is looking good. I bought this model because it is pretty average in terms of performance, but mostly because it was cheap to buy four of them! You can polish off this project with an uninterruptible power supply (UPS). Connected through USB 3.0, a SATA SSD is no slouch, but if you want the best possible performance on the Pi, using direct NVMe or SATA SSD storage is the best option. I have seen the power supply 12V/2A you use for feeding 4 x Kingston SSD, but not the one for 4 x HDD. Nicola King sees LEDs in a new light, Michael Pick is so excited to show you his tiny homage to Appleâs iconic machine, as David Crookes discovers, Add a super-fast M.2 SATA SSD to Raspberry Pi 4 along with dual full-sized HDMI sockets, a power button and fan cooling. Using the Raspberry Pi as an always-on NAS box sounds like a wonderful use of the silent little device. Is it the 1GB, 4GB or 8GB version. So what is a NAS, anyway? I want to replace my old NAS with a low-energy but powerful replacement. Wanted to place a RPi 4 compute module and IO in a generic 1U rack mounted shallow depth server case and, naturally, that'd require the SATA card to be in a riser rather than standing upright. Purchasing & Delivery You may be liable for import duties, sales tax, or customs processing fees. Prep your storage. Once booted, make sure SSH has been enabled by running sudo raspi-config and selecting Interfacing Options > SSH. The ideal solution is to use a cloud provider such as Google or Dropbox to back everything up. Sudden power cuts can spell disaster for Linux-based systems due to the way they handle files in memory. The post mdadm: device or resource busy had the solution—disable udev when creating the volume, for example: You may also want to watch the progress and status of your RAID array while it is being initialized or at any given time, and there are two things you should monitor: And if all else fails, resort to Google :). In my Raspberry Pi NAS, I currently have one powered 4TB HDD, one non-powered 4TB HDD and a 128GB flash drive mounted without issue. Hi, How much ram does the Raspberry Pi Compute Module 4 have? Now only that user can access that directory. I will also release a new instructable on this topic soon with improved casing and software. NAS can be expensive. Really interesting article. Thanks to Alex Ellis and Emmet Young for their excellent blog posts on RAID and Samba. Since the day I received a pre-production Raspberry Pi Compute Module 4 and IO Board, I've been testing a variety of PCI Express cards with the Pi, and documenting everything I've learned. It turns out that SATA chips are very difficult to get a hold of and JMicron is the only one that has been responsive. Specifically useful for Raspberry Pi 2+ and a nice alternative to untrustworthy RAID systems. When prompted for a command, enter ânâ for new partition. In simpler terms, itâs a box on to which you dump all your movies, photos, music, and other stuff so you can get to it wherever and whenever. At this point, we have four independent disks, each with one partition spanning the whole volume. The first thing I wanted to test was whether a SATA drive—in this case, a Kingston SATA 3 SSD—would run faster connected directly through a SATA controller than it ran connected through a USB 3.0 controller and a UASP-enabled USB 3.0 to SATA enclosure. This is a pretty awesome article, man. We'll then look at whether that improves performance for I/O intensive tasks such as pulling a Docker image down from the public registry. Did you find any solution to what you suspect is linux flushing to disk and starving the nic of io bandwidth, continuously tanking the network transfer speed? Utilities such as Rclone can sync entire directory structures onto many different providersâ storage. Install the hard drives in the enclosures, â¦ Inside youâll discover a 20-page feature celebrating 100 moments from Raspberry Pâ¦. Just - wow. If youâve got a lot of files like photos, music, or movies, chances are they are sitting on a hard drive somewhere. The files themselves should be available with appropriate security measures over desired protocols. Make a crazy Christmas game and guide Santa on his Christmas Eve run, delivering the MagPi magazine, LED cubes may not be new, but one maker has created a cube with a USP â a status monitor for his PC. Next, we need to partition the drives so Raspbian can understand how to store data on them. ... Configuring RAID 5. Hi thank you for sharing this valuable information. The results weren't promising, and has me thinking of using my Intel NUC instead since it has several USB 3 ports. But I would definitely like someone to design a nice case that holds the Pi, a specialized (smaller) IO board, a PCIe SATA adapter, a fan, and four SATA drives—ideally designed in a nice, compact form factor! Should the Raspberry Pi NAS fail for some reason or we want to quickly copy information over a USB 3.0 connection instead of via the network, having NTFS-formatted disks makes it dead simple to take the portable USB drives weâre using on the NAS build and plug them right into one of the many Windows machines we use every day. Next I wanted to benchmark a single WD Green 500GB hard drive. I'm going to create a RAID 10 array for my own use—you can check out the associated video linked above for the reasons why I chose RAID 10 instead of something else. - The (roughly) 5Gbits of PCIe are always going to be bottlenecked by the 1Gbit of Ethernet. (Raspberry Pi 4 is too hard to get at the moment, but I will see if I can get one soon :P ) Raspberry Pi 4 support will definitely be added soon, with its on board USB3.0 port and Gigabyte Ethernet, it is the best board to setup a Raspberry Pi NAS. Raspberry Pi 4 offers USB 3.0, so make sure you get external USB drives that take advantage of that extra speed. fdisk will now exit. No link for the RPI4? The Raspbian version of this has the slightly more friendly name of Samba, but it is not installed by default. For the first solution, we will be using a software called Samba to build a NAS with Raspberry Pi. Could I send you some to try? So there are other IO pressures that the Pi reaches that make RAID for SATA SSDs less of a performance option than for spinning hard drives. Just keep pressing ENTER (accepting the defaults) until âCreated a new partitionâ appears. Download Raspbian Buster Lite and burn it to a microSD card. In reply to Thank you for sharing your… by Gonzalo. Prerequisites for installing a NAS. RAID is not a backup system. Well, I'm also testing some PCI multi-port switches with the Pi—follow that issue for progress.). The Raspberry Pi, on the other hand, is such a versatile little board that it can act as a cheap trial NAS thatâonce you grow out of itâcan be repurposed for something else. Or it… by Jason Harrison. The setup is headless, meaning we access the RaspberryPi only via remote SSH controls. First, weâre using NTFS-formatted hard disks. Save 37% off the cover price with a subscription to The MagPi magazine. For example, when I was trying to format four HDDs the first time, I got: And the solution I found in this StackOverflow question was to run: I also ran into the message Device or resource busy when I tried formatting four SSDs, and it would always be a different device that was listed as the one being busy. The Raspberry Pi 4 is a big improvement over the RPI 3 on many fronts. Quit (CTRL+X, followed by Y), then run the following so the RAID array starts up correctly on boot: Reboot and you should have /mnt/raid1 ready to go. Next, make sure that the drive is mounted whenever you boot. If you want to create file shares that are private to individual users, just create their own directory on the RAID array: Again, replace username with the user you want. New Raspberry Pi 4 USB 3.0 Personal Cloud With RAID Backup: Hello and welcome. Make it available anywhere in your home with your own Raspberry Pi network-attached storage, The MagPi magazine is 100 issues young. So why do you think it matters if your drives are USB or SATA attached? Getting started with the Raspberry Pi Set up your Raspberry Pi and explore what it can do. As you can see, connected directly via SATA, the SSD can give noticeably better performance on all metrics, especially for small file random IO, which is important for many use cases. Just add your Raspberry Pi 4 to this Kit and your NAS is complete and it really looks great! I already have prepared a NAS with my raspi 4, and I was wondering what power supply are you using for feeding 4 x WD HDD. 04 December 2016 on Raspberry PI, DevOps, nas, benchmarking, nfs, ssh In this tutorial we'll convert a stock Raspbian Lite OS into a NAS with two 314GB WDLabs PiDrives in a RAID-1 array. So for each of my devices (sda through sdd), I ran fdisk to create one primary partition: There are ways you can script fdisk to apply a given layout to multiple drives at the same time, but with just four drives, it's quick enough to go into fdisk, then press n, then press 'enter' for each of the defaults, then w to write it, and q to quit. It seemed to work in both cases, though I did my actual benchmarks for the HDDs while they were connected through a 600W power supply (overkill, I know!). What about a power switch and display / indicator for status? dmraid 10 is not exactly 1+0. I can imagine an enclosure... thanks for giving this idea some new strength. Thoughts on which you’d prefer? In my case, it's already faster than the old Mac mini I have been using as a NAS for years, which has only USB 2.0 ports, limiting my file copies over the network to ~35 MB/sec! This article first appeared in The MagPi 85 and was written by PJ Evans. Above all, it is important to present the necessary material for this â¦ Donât panic. Anything written to one disk is automatically written to the other. Have you been able to test different SATA chipsets? The ROCK Pi SATA HATs come in 3 models: If you have two USB disks installed and working, you should also see âsdaâ and âsdbâ (Storage Device A and Storage Device B). Instead of using the RAID function on these boards, configure each drive in JBOD and use ZFS to create volumes. I’ve been wondering about using Pi for a Raid1 with 1 or 2 TB SSDs for storing high value data backups. The most important decision youâll make is how much storage youâll need. This way I can keep the Raspberry Pi's environments relatively light and have an environment I can add onto as I need the additional power. Our NAS can now create file shares, the most basic of capabilities. It does striping and mirroring "combined" instead of one after the other. Thanks for answering. A well-implemented, network-attached storage device is typically a headless device (no keyboard or monitor) providing access to large amounts of data from anywhere on your network. Professional NAS software often offers additional protocols such as Apple AFS, FTP, and many others. I'm pretty sure this is also what I'm running into with my laptop usb drive raidz nas that's limited by the 1x pcie lanes to the pch. Run the following: If you are asked any questions, just select the default answer. For my board, I’m currently eying the JMB582 or JMB585 which are pci to 2 or 5 port SATA chips, respectively. Speaking of network traffic, the last test I did was to install and configure both Samba and NFS (see Samba and NFS installation guides in this issue), to test which one offered the best performance for network file copies: It looks like NFS holds the crown on the Pi, though if you use Windows or Android/iOS primarily, you might see slightly different results or have a harder time getting NFS going than Samba. ( I don't know if it supports raid, but there are Free NAS and others with GUI). If youâve enabled SSH, youâve already got SFTP available; just connect using your favourite FTP client using /mnt/raid1/shared as the starting point. I ran into a few different issues when formatting different sets of disks. Use your favorite program to unzip the file â I used 7zip, which you may â¦ With the Raspberry Pi up to date, we can go ahead and install the packages that we will be relying â¦ It provides a certain level of data redundancy, but will not be of any help if you accidentally delete a file. You only have one PCIe lane to work with whether you have a regular rpi4 (the USB3 is attached to it) or you have an expansion card. Using the powered USB 3.0 hub connected to your Raspberry Pi, plug in all your USB disk drives. â¦where âusernameâ is your choice of username. I have full directions for recompiling the kernel with SATA support on the Pi itself, too! In your benchmarks did you try to play with raid10 layout options (near, far, ...); I was always wondering how the impact performance for spinning HDD versus SSD. Now letâs make a directory and allow all users access: Tell Samba to share the directory on the network by editing the config file: Save (CTRL+X, followed by Y), then restart Samba: To give a user access to the shared files, we need to run a special command to set a Samba password. Most of these can also be implemented on a Raspberry Pi NAS. I was leaning toward a 2 port NAS since 3.5 in hard drives are available in 18tb and soon 20tb variants. You probably get better efficiency if you use something like LVM and share a logical volume (rather than a file). Once that's done, you should be able to see any drives attached to the card after boot using lsblk, for example: (Wait... how is there also an NVMe drive there?! Thank you for sharing your benchmark and all the steps. But it's a good option if you just want to have external storage. First, install the software RAID manager, mdadm: Now instruct mdadm to create the RAID-1 array: Raspbian will now see both physical disks as a single device. Why not set up a DLNA streaming server or run multiple databases? After switching to the appropriate keyboard language, it â¦ Once done, the user âpiâ can access the Samba share from Windows, macOS, or other Raspberry Pi devices, with the ability to read and write files. I linked to those in my initial Pi Compute Module 4 Review post. Installing Ubuntu Server. It looked like a race condition of some sort, and after some Googling, I found out that's exactly what it was! This battery backup safely keeps your Raspberry Pi and hub running in the event of a power cut. Did you look at the energy consumption of your setup? Great write up, was thinking about this as a project (at some stage), you've given me so much really useful information and many new tabs! You can format and mount the new virtual drive: You should see one item: âlost+foundâ. Top of page. It must also offer availability and resilience for your data. Raspberry Pi OS (and indeed, any OS optimized for the Pi currently, like Ubuntu Server for Pi) doesn't include all the standard drivers and kernel modules you might be used to having available on a typical Linux distribution. Designing a Raspberry Pi NAS using external USB drives. Plus, power requirements would be far lower. I had and NAS together so the intent is to set up the NAS for local network storage for my videos and documents but also as storage for the volume data used by the docker containers. Thanks for sharing your work and good luck! Using the Raspberry Pi 4, with portable USB drives configured in a Linux RAID configuration. I think the Compute Module 4, with it's built-in Gigabit networking and ability to use one or more PCI Express cards, is the first Raspberry Pi that I would consider 'good' for running a reliable and performant NAS. But I decided to go all out (well, at least within a < $100 budget) and buy three more Kingston SSDs to test them in the same RAID configurations: And it was a little surprising—since the Raspberry Pi's PCI Express 1x 2.0 lane only offers around 5 Gbps theoretical bandwidth, the maximum real-world throughput you could get no matter how many SSDs you add is around 330 MB/sec.