Updating Thecus n5550 NAS to report over 3GB of RAM

Out of the box, the Thecus N5550 NAS will only report that 3GB is available, even if you have 4GB or more of RAM installed. Apparently, this is due to the N5550 reserving 1 GB for the Local Display Module, which is used to administer the NAS using an external monitor rather than by the web server. The Thecus N5550 forums have some additional details about this. If like me, you do not require the Local Display Module, you can disable the effects of this memory reserve by updating the kernel boot arguments on the N550.

NOTE: Updating boot arguments can seriously harm you NAS is done incorrectly. I take no responsibility if your system is harmed, or you lose data. Make backups of your data before any risky updates. You've been warned. 

Updating the kernel boot arguments requires root SSH access to your NAS. To enable this, go to Home > Network Service > SSH and enable the SSH Service. Next open up a terminal and SSH into the N5550 using the root user. The root password should be the same as the password for the admin user in the web server.

camille:~ astro$ ssh root@10.0.0.120

root@10.0.0.120's password: 

Note:

    Please do not delete or modify any files or folders or it may result in system operation abnormal.

holly:~#

Next, mount the boot partition of the NAS.

holly:~# mount /dev/sdaaa1 /boot

holly:~# ls -al /boot

drwxr-xr-x    4 root     root          1024 Jun  5  2013 ./

drwxr-xr-x   26 root     root          1024 Feb  3 21:08 ../

drwxr-xr-x    3 root     root          1024 Nov 20 23:39 boot/

drwx------    2 root     root         12288 Jun  5  2013 lost+found/

holly:~# 

Now open up /boot/boot/grub/menu.lst using vi.

holly:~# vi /boot/boot/grub/menu.lst 

You should see something like the following:

default=0                                                                                                                

timeout=0                                                                                                                

hiddenmenu                                                                                                               

title Normal                                                                                                             

    root(hd0,0)                                                                                                          

        kernel (hd0,0)/boot/bzImage ro root=/dev/ram0 max_loop=210 console=ttyS1,115200n8 mem=4G video=LVDS-1:d          

        initrd (hd0,0)/boot/ramdisk                                                                                      

title Backup                                                                                                             

    root(hd1,0)                                                                                                          

    kernel (hd1,0)/boot/bzImage ro root=/dev/ram0 max_loop=210 console=ttyS1,115200n8 domb                               

    initrd (hd1,0)/boot/ramdisk                                                                                          

~                                                                                                                        

~                                                                                                                        

~                                                                                                                        

- /boot/boot/grub/menu.lst [Modified] 6/11 54%

Do a quick search about using vi if you are not familiar with using it (I personally use GNU Emacs), but you should be able to move to using the arrow keys, and press i to enter insertion mode (editing). Remove the text that says mem=4G, and save the file and quit by hitting escape then : (colon), and wq! .

Now exit your SSH session.

holly:~# exit

logout

Connection to 10.0.0.120 closed.

camille:~ astro$ 

Disable SSH access to your N5550 by going to Network Service > SSH, and reboot your NAS by going to Home > System Management > Power Management and select Reboot. When your N5550 has rebooted, you should see 4GB (4003MB) of RAM reported under Home > System Information > Hardware Information.

Cheers,

Astro Weasel