Armbian on external USB SSD

[napo7]

Hi

 

I managed to get armbian on my Amlogic S905W device.

I'd like to run the whole root fs on an external usb device (ssd).

I know how to format it to ext4, mount it, but I can't manage to boot linux on it :

I tried to modify the /etc/fstab file, but it seems that it's not the good place ?

Perhaps a file in /boot ?

[balbes150]

Where is the BOOT partition and kernel files with startup scripts?

[napo7]

Hmmm Good question !

I don't know, I suppose in some /dev/mmc.... device ? It's the stock image (an x96 mini tv box)

 

I'm very comfident with linux on desktop, servers and rpi, but not with this kind of devices (uboot ?)

 

s905_autoscript contains :

setenv initrd_loadaddr "0x13000000"
setenv init_hdmi "logo=osd1,loaded,${fb_addr},${hdmimode} vout=${hdmimode},enable"
setenv condev "console=ttyS0,115200n8 console=tty0 no_console_suspend consoleblank=0"
setenv bootargs "root=LABEL=ROOTFS rootflags=data=writeback rw ${init_hdmi} ${condev} fsck.repair=yes net.ifnames=0 mac=${mac}"
setenv boot_start booti ${kernel_loadaddr} ${initrd_loadaddr} ${dtb_mem_addr}
if fatload usb 0 ${initrd_loadaddr} uInitrd; then if fatload usb 0 ${kernel_loadaddr} zImage; then if fatload usb 0 ${dtb_mem_addr} dtb.img; then run boot_start; else store dtb read ${dtb_mem_addr}; run boot_start;fi;fi;fi;
if fatload usb 1 ${initrd_loadaddr} uInitrd; then if fatload usb 1 ${kernel_loadaddr} zImage; then if fatload usb 1 ${dtb_mem_addr} dtb.img; then run boot_start; else store dtb read ${dtb_mem_addr}; run boot_start;fi;fi;fi;
if fatload usb 2 ${initrd_loadaddr} uInitrd; then if fatload usb 2 ${kernel_loadaddr} zImage; then if fatload usb 2 ${dtb_mem_addr} dtb.img; then run boot_start; else store dtb read ${dtb_mem_addr}; run boot_start;fi;fi;fi;
if fatload usb 3 ${initrd_loadaddr} uInitrd; then if fatload usb 3 ${kernel_loadaddr} zImage; then if fatload usb 3 ${dtb_mem_addr} dtb.img; then run boot_start; else store dtb read ${dtb_mem_addr}; run boot_start;fi;fi;fi;
if fatload mmc 0 ${initrd_loadaddr} uInitrd; then if fatload mmc 0 ${kernel_loadaddr} zImage; then if fatload mmc 0 ${dtb_mem_addr} dtb.img; then run boot_start; else store dtb read ${dtb_mem_addr}; run boot_start;fi;fi;fi;

 

[balbes150]

Write in detail all your steps, what and where you copied, what you did with the media, etc.

[napo7]

I've made :

dd if=/dev/data of=/dev/sda1

then

resize2fs /dev/sda1

 

edited /etc/fstab to change "/dev/root" to "/dev/sda1"

 

When I rebooted and typed "mount" to verify, root fs was still mounted from /dev/data...

 

Is /etc/fstab really used to mount rootfs ? I suppose It's a kernel commandline option in facts.

I suppose I have to change the s905_autoscript, but I don't know the syntax and how to modify it ? (it seems to contain binary data in header section ??)

[balbes150]

On 6/11/2018 at 9:59 PM, napo7 said:

I've made :

dd if=/dev/data of=/dev/sda1

then

resize2fs /dev/sda1

 

edited /etc/fstab to change "/dev/root" to "/dev/sda1"

 

When I rebooted and typed "mount" to verify, root fs was still mounted from /dev/data...

 

Is /etc/fstab really used to mount rootfs ? I suppose It's a kernel commandline option in facts.

I suppose I have to change the s905_autoscript, but I don't know the syntax and how to modify it ? (it seems to contain binary data in header section ??)

I don't understand why you are trying to install the system in eMMC from the beginning and then try to change the rootfs location ? Immediately write the system image to an external media and use it.

[napo7]

Sorry :)

I didn't knew I could install the system on an external media... thought I could only be done on a sd card...

 

So, the instructions are just : 

write image on SSD, boot on SSD. done !?

[balbes150]

yes (USB->SSD)

But please note that the speed through USB 2.0 is very low.

[napo7]

It worked. 

thanks !

In facts, SSD over USB 2.0 is anyway faster than internal MMC !!

I run a MYSQL server (for home automation), and it is 60 times faster to make 1000 "insert into" on the database on SSD than internal memory !

 

Thanks for your help...

 

[balbes150]

21 hours ago, napo7 said:

In facts, SSD over USB 2.0 is anyway faster than internal MMC !!

I run a MYSQL server (for home automation), and it is 60 times faster to make 1000 "insert into" on the database on SSD than internal memory !

This is weird. The result should be the exact opposite. If so, eMMC does not work correctly (there may be different reasons).

[napo7]

I don't know the specifications of this eMMc, but i saw "cheap computers" with 32gb of MMC which was slower than a good Sandisk SSD.