DSM 5 on Synology DS409slim

Looking at the DiskStation DS414slim, I discovered that DSM was now available in version 5. But it wasn’t available from the DSM 4.2 control panel on my DS409slim. After a few Internet diggings, I learned that it should be possible to install DSM5 on a DS409slim. The main trick is to fake another DS. Looking at CPUs in Synology’s NAS, you can see that DS409slim and DS411j share the same Marvell Kirkwood mv6281 CPU and 16-bit@DDR2 architecture. That’s the trick to be able to use DSM5 on DS409slim.

First thing to do is to backup your data. You will not hold me responsible or liable for any loss or damage of any sort (…) ;-)

Now, connect to the DSM Web interface and update the DS409slim. The latest available version was DSM 4.2-3251.

DSM 4.2-3251

Enable SSH daemon and connect to the Synology DS409slim using SSH. Check the system informations:

ds409slim> uname -a
Linux ds409slim #3251 Tue Aug 19 12:33:00 CST 2014 armv5tel GNU/Linux synology_88f6281_409slim

Edit the /etc.defaults/synoinfo.conf file and replace




Go back to the DSM Web interface and browse to “Control Panel – DSM Update”. After a while, you’ll see that “DSM 4.3-3827 is available for download”. Click the “Download”, then the “Update Now” buttons.

DSM 4.3-3827 is available for downloadDSM 4.3-3827 download...DSM 4.3-3827 update...

Wait while upgrade proceeds and NAS reboots. When done, log in to the Web GUI and browse to “Control Panel – DSM Update”. You will notice that the “Model name” is now “DS411j” and that “DSM 5.0-4493 is available for download”. As before, download and apply the upgrade.

DSM 5.0-4493 is available for download.DSM 5.0-4493 is ready for update.

The upgrade process will proceed and the NAS will reboot. In my case, it lasted less than 5 minutes.

Once again, log into the Web GUI and browse to “Control Panel – DSM Update”. You’ll have to run the DSM5 wizard before being able to log into the admin pages.

DSM5 on DS409slimDSM5: Welcome!DSM5: Set up QuickConnectDSM5: You Are All Set!

In my case, I was notified that “DSM 5.0-4493 update 4 is available for download”. So I went for the upgrade and another reboot cycle.

DSM 5.0-4493 update 4 available DSM 5.0-4493 update 4 installing... Your DSM version is up-to-date.

Last thing to do is to update the installed packages. This is done through the Web GUI. Browse to “Package Center – Update” and click “Update All”. This process did last for quite a while here ; about 10-15 minutes. But everything is automatic so you don’t have to stand in front of the Web browser while processing to updates.

Package Center updates Package Center Notifications

From here, the DS409slim is ready to use. A forum post I found notified that another trick has to be used to enable e-SATA connectivity ; as DS411j doesn’t have such port. I don’t use e-SATA so I didn’t check if  it is working or not ; let me know ;-) Anyway, you have to log in using SSH and edit the /etc.defaults/synoinfo.conf file. Check that


and replace




While you’re in console, have a look at the system information and compare with the initial value:

ds409slim> uname -a
Linux ds409slim #4493 Thu Aug 21 21:43:08 CST 2014 armv5tel GNU/Linux synology_88f6281_411j

Reboot to apply the e-SATA tweak and that’s all for it. Now enjoy you’re DS409slim with DSM5.0!

Author: Joel Carnat

@work Technical Architect and SysAdmin ; @home OpenBSD and FOSS, Karate, Kobudō, Jōdō, Bodyweight workout, Photography & Music

7 thoughts on “DSM 5 on Synology DS409slim”

  1. Yes…. Bravo….

    I can’t wait to try it on my old 409Slim.
    Thanks for the Job.

    Please can you tell me how to: “Enable SSH daemon and connect to the Synology DS409slim using SSH” and “how to Check the system informations”


  2. I updated the synoinfo.conf file, after that syno assistant recognise the NAS under the “new” name
    but not accepting any update files.
    Can’t change config back because SSH not available anymore…
    I can view it via TELNET, but there I can’t edit it back to the old version.
    Now I can’t re-install the old version because its thinks its new now, so there is a version mismatch,
    Any idea how I can enable SSH again?

  3. hi Joel,
    I tried but that command is not recognised / accepted.
    other option would be to export out the synoinfo.conf file
    then edit it back how it was and copy back.
    How can I do that in a telnet session? I use “cp” but I can copy only inside nas and not export to local pc.


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