Emmc

[mariusares]

Hi
First of all thank you for your great work.
It's like a nice surprise ...

I have installed the bare ubuntu with kernel 14.7 from :
https://mega.nz/#!obIAVQiA!G0CCABkLunCcG8hEqMf7NfjTBK1jgMytt2f0VdtOl08
I can't see the emmc on fdisk ...
Do you recommend a different kernel version?
Is any chance to have a bare debian 10 os with a stable kernel too? I mean on debian/Raspbian you have 2 kernels. Version 3 what runs ok and smoothie but is no AP network mode compatible and Version 4,4 where load average is pretty high (over 1 on idle)
For those who use i2c, gpio, spi, serial and wifi ap mode, a bare system is great.
Thank you for your time

[avafinger]

I can't see the emmc on fdisk ...
A: BananaPi M2Z does not have eMMC!

Do you recommend a different kernel version?
A: Scroll down the github page and you see the kernel history and new kernel versions, personally i like the kernel 5.3 and 5.7.
Kernel 5.3 has great CPU Temp management and performance, Kernel 5.7 has a lot of bug fixes and it is maintained by the Linux community.

Is any chance to have a bare debian 10
A: Sorry, i am an Ubuntu user but would like to move to Debian, it can happen soon or take years.
The idea behind this Image is to have a CLI (Command Line Interface and minimal) with few installed packages, M2Z has 512 MB of DRAM, users will not be pleased to run a Full Desktop, yet it is possible. You can install LXDE or try Armbian.

Start with this IMG and upgrade the kernel to 5.7:
https://github.com/avafinger/bananapi-zero-ubuntu-base-minimal/releases/tag/v2.4

Upgrade Kernel:
https://github.com/avafinger/bananapi-zero-ubuntu-base-minimal/releases/tag/v3.7

Kernel and some IMG releases:
https://github.com/avafinger/bananapi-zero-ubuntu-base-minimal/releases

[mariusares]

I understand, i chose banana pi over raspberry pi because rpi won't implement eMmc on their boards anytime soon, but it's so poor on software support.
Thanks to people like you who color a bit that side of the room :)
I'll try to get your kernel sources to compile them in a debian system ... When I'll get some time to be honest ...

[avafinger]

This board has eMMC but the layout is a bit different:
http://www.banana-pi.org/m2pz.html

[mariusares]

This is the board i have right now
Si basically you are suggesting to upgrade the os image from Ubuntu 16.4 to ubuntu 19.* and kernel 5.7
I understand that Ubuntu 16.4 it's LTS correct?
Can I use the kernel 5.7 and configuration on Ubuntu 16.4?
I probably look stupid but i cant find the download links :)
Thank you

[mariusares]

I got the links
Sorry I'm on mobile so ...

[avafinger]

Ubuntu 19.10

[avafinger]

Ubuntu 19.10 - Eoan Ermine with Kernel 5.3.5

[avafinger]

Can I use the kernel 5.7 and configuration on Ubuntu 16.4?
yes, i think it is possible, but the deb package will install the modules in /usr/lib/modules and i think Ubuntu 16.04 LTS has it in /lib/modules

If after you boot and you don't see the modules with lsmod you will have to move /usr/lib/modules/KERNEL_VERSION to /lib/modules/

If this happens you won't be able to ssh to the board and will need to use HDM or the serial debug

[mariusares]

I'll give it a try.
What I need is Gpio, uart, i2c , spi , eth, wlan+ap mode and stability ...
Let me install it and I'll get back to you
Thank you

[mariusares]

ok so kernel 5.3 and 5.7 only detects /dev/mmcblk0 ...
there is no way to detect eMMC for some reason
any clue please?
U-Boot SPL 2017.09-h2 (Jul 06 2018 - 10:16:12)
DRAM: 512 MiB
Trying to boot from MMC2
MMC Device 1 not found
spl: could not find mmc device. error: -19
SPL: failed to boot from all boot devices

ERROR ### Please RESET the board

This is with the image flashed on eMMC ...
works on sd card but not on eMMC ...

[avafinger]

Try this:

1 - Update u-boot (only the bootloader) from this tag:
https://github.com/avafinger/bananapi-zero-ubuntu-base-minimal/releases/tag/v1.7

2 - make sure eMMC is active
#18

3 - Make sure the root device is correct for eMMC, change it in /boot/boot.cmd

[mariusares]

there is no /dev/sd* ...
dd if=./bootloader_2z_v3.bin conv=notrunc bs=1k seek=8 of=/dev/mmcblk0p1
so /dev/mmcblk0p1 is the /boot sd card partition ...
is that OK?

[avafinger]

/dev/sd* is for USB SDHC reader/writer (if you connect to a PC box running Linux)
/dev/mmcblk0p1 that is OK if you do from M2Z

[mariusares]

i did this :
#11 (comment)
basically i can see the eMMC now but i cant boot from eMMC ... do you have the kernel+kernel config able to boot from eMMC or we have to do that manually? im on Ubuntu 19.10 now with kernel 5.3 ...
root@bpi-m2z:# uname -a
Linux bpi-m2z 5.3.5 #1 SMP Mon Oct 7 21:22:23 -03 2019 armv7l armv7l armv7l GNU/Linux
root@bpi-m2z:# fdisk -l
Disk /dev/mmcblk0: 29.29 GiB, 31439454208 bytes, 61405184 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x2474af91

Device Boot Start End Sectors Size Id Type
/dev/mmcblk0p1 49152 253951 204800 100M 83 Linux
/dev/mmcblk0p2 253952 15777791 15523840 7.4G 83 Linux

Disk /dev/mmcblk2: 7.29 GiB, 7818182656 bytes, 15269888 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x2474af91

Device Boot Start End Sectors Size Id Type
/dev/mmcblk2p1 49152 253951 204800 100M 83 Linux
/dev/mmcblk2p2 253952 15777791 15523840 7.4G 83 Linux
root@bpi-m2z:~#

[mariusares]

i`m trying to change some settings here

setup boot_device

fdt set mmc${boot_mmc} boot_device <2>

and i get the same result on boot
U-Boot SPL 2017.09-h2 (Jul 06 2018 - 10:16:12)
DRAM: 512 MiB
Trying to boot from MMC2
MMC Device 1 not found
spl: could not find mmc device. error: -19
SPL: failed to boot from all boot devices

ERROR ### Please RESET the board

[mariusares]

There is no boot.cmd ... I'll try to decompile boot.scr and edit it in order to take action ...
Let's see the result ...

[avafinger]

boot.cmd.tar.gz

to be able to boot from eMMC you have to format it and copy the bootloader, boot, and rootfs.
There is a script that does that, search the releases and find the latest and instead of passing /dev/sdX you will pass /dev/mmcblkY

[mariusares]

well is not working for me unfortunately ...

[avafinger]

Boot from SD card and see what you get with this command:

ls /dev/mmcblk*

[mariusares]

root@bpi-m2z:# ls /dev/mmc*
/dev/mmcblk0 /dev/mmcblk0p2 /dev/mmcblk2boot0 /dev/mmcblk2p1
/dev/mmcblk0p1 /dev/mmcblk2 /dev/mmcblk2boot1 /dev/mmcblk2p2
root@bpi-m2z:#
its strange ...
the bootloader should read the sd card and emmc as well ...

[avafinger]

1 - when booting from SD CARD:
/dev/mmcblk0 is your SD CARD
/dev/mmcblk2 is your eMMC

2 - when booting without SD CARD

/dev/mmcblk? - It changes device number, you should figure out what number will be, possible 1.

3 - Update u-boot with: https://github.com/avafinger/bananapi-zero-ubuntu-base-minimal/releases/tag/v3.4

4 - Use this scripts to format and install kernel and rootfs and update bootloader with the new version:
https://github.com/avafinger/bananapi-zero-ubuntu-base-minimal/releases/tag/v15

              sudo ./format_sd_mainline.sh  /dev/mmcblk2
              sudo ./flash_sdcard_mz2_v2.sh  /dev/mmcblk2

reboot without SD CARD, i think a debug ttl uart is indispensable

[avafinger]

try:
fdt set mmc${boot_mmc} boot_device <boot_mmc>

[mariusares]

i`m controlling the board via uart ttl
the image does not see emmc without modification
the bootloader does not boot from emmc

https://github.com/avafinger/bananapi-zero-ubuntu-base-minimal/releases/tag/v3.4

fdisk -l:
root@bpi-m2z:~# fdisk -l
Disk /dev/mmcblk0: 29.29 GiB, 31439454208 bytes, 61405184 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x2474af91

Device Boot Start End Sectors Size Id Type
/dev/mmcblk0p1 49152 253951 204800 100M 83 Linux
/dev/mmcblk0p2 253952 15777791 15523840 7.4G 83 Linux
root@bpi-m2z:~#

still can`t see the emmc ...
so i have to use

#11 (comment)
bpi-m2-zero-v4.dtb_eMMC.zip

with this dtb the emmc is /dev/mmcblk2 and i dont think that would be changed after that ... so ... i dont know what would be the resolution ...

[avafinger]

This DTB has eMMC enabled, try with this dtb.
bpi-m2-zero-v4.dtb_emmc.tar.gz

• unzip it into /boot
• sudo ln -sf bpi-m2-zero-v4.dtb_emmc bpi-m2-zero-v4.dtb
• sync && sudo reboot

This for kernel 5.7.x-server

[mariusares]

you mean this one?
https://github.com/avafinger/bananapi-zero-ubuntu-base-minimal/releases/tag/v3.7

i can only see that 5.7 kernel but no "server" tag on it

[avafinger]

yes!

[mariusares]

this is output from sd-card boot
root@bpi-m2z:~# fdisk -l && uname -a && ls -la /boot && cat /etc/issue*
Disk /dev/mmcblk0: 29.3 GiB, 31439454208 bytes, 61405184 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x58b49123

Device Boot Start End Sectors Size Id Type
/dev/mmcblk0p1 49152 253951 204800 100M 83 Linux
/dev/mmcblk0p2 253952 15532031 15278080 7.3G 83 Linux

Disk /dev/mmcblk2: 7.3 GiB, 7818182656 bytes, 15269888 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x58b49123

Device Boot Start End Sectors Size Id Type
/dev/mmcblk2p1 49152 253951 204800 100M 83 Linux
/dev/mmcblk2p2 253952 15532031 15278080 7.3G 83 Linux
Linux bpi-m2z 5.7.6 #1 SMP Sun Jun 28 00:11:55 -03 2020 armv7l armv7l armv7l GNU/Linux
total 12220
drwxrwxr-x 3 ubuntu ubuntu 4096 Jul 3 17:39 .
drwxr-xr-x 21 root root 4096 Jan 15 2018 ..
lrwxrwxrwx 1 root root 20 Jan 15 2018 boot.scr -> bpi-m2-zero_boot.scr
-rw-r--r-- 1 root root 26886 Jul 6 2018 bpi-m2-zero-v1.dtb_4.17.4-m2z
-rw-r--r-- 1 root root 27076 Jul 6 2018 bpi-m2-zero-v2.dtb_4.17.4-m2z
-rw-r--r-- 1 root root 28817 Jun 28 04:30 bpi-m2-zero-v4.dtb_5.7.6
-rw-rw-r-- 1 ubuntu ubuntu 28813 Jul 3 16:15 bpi-m2-zero-v4.dtb_emmc
lrwxrwxrwx 1 root root 23 Jul 3 17:39 bpi-m2-zero.dtb -> bpi-m2-zero-v4.dtb_emmc
-rw-r--r-- 1 root root 924 Jul 6 2018 bpi-m2-zero_boot.cmd
-rw-r--r-- 1 root root 996 Jul 6 2018 bpi-m2-zero_boot.scr
-rw-rw-r-- 1 ubuntu ubuntu 978454 Jul 6 2018 initrd.img
drwx------ 2 root root 16384 Nov 5 2017 lost+found
lrwxrwxrwx 1 root root 12 Jul 3 17:34 zImage -> zImage_5.7.6
-rwxr-xr-x 1 root root 5376808 Jul 6 2018 zImage_4.17.4-m2z
-rwxr-xr-x 1 root root 6000368 Jun 28 03:48 zImage_5.7.6
Ubuntu 16.04.4 LTS \n \l

Ubuntu 16.04.4 LTS
root@bpi-m2z:~#

dd if=/dev/mmcblk0 of=/dev/mmcblk2 bs=10M status=progress
then i removed the sd-card and boot from eMMC ...
output:

U-Boot SPL 2020.04 (Apr 21 2020 - 14:52:45 +0000)
DRAM: 512 MiB
Trying to boot from MMC2
MMC Device 1 not found
spl: could not find mmc device 1. error: -19
SPL: failed to boot from all boot devices

ERROR ### Please RESET the board

on Ubuntu 19.10 the same ... so that dtb has a problem by booting from emmc ...

[avafinger]

Who told you this instructions would work?

dd if=/dev/mmcblk0 of=/dev/mmcblk2 bs=10M status=progress
then i removed the sd-card and boot from eMMC ...

[mariusares]

well how can i boot from eMMC ?

[avafinger]

Trying to boot from MMC2
MMC Device 1 not found

boot.cmd must tell the boot loader what device number eMMC is.
If you boot with SD CARD, eMMC has ID number X, if you boot WITHOUT SDCARD eMMC has ID number Y.

I will release a new Kernel and will prepare the script for writing to eMMC and try to guess which ID number we can try.
This takes some time, i am at work now.

Meanwhile, you can edit the boot.cmd (mount it booting with SD CARD) and recompile it to .scr, unmount it, and reboot.
Try Device number 2

[avafinger]

root=/dev/mmcblk0p2 => adjust to root=/dev/mmcblk1p2
and fstab

[mariusares]

[ 2.532005] Run /init as init process
Kernel params: console=ttyS0,115200 earlyprintk rootfstype=ext4 root=/dev/mmcblk1p2 rw rootwait fsck.repair=yes panic=10 no_console_suspend consoleblank=0 drm_leak_fbdev_smem=1
Waiting for root system /dev/mmcblk1p2, countdown : 5
Waiting for root system /dev/mmcblk1p2, countdown : 4
Waiting for root system /dev/mmcblk1p2, countdown : 3
Waiting for root system /dev/mmcblk1p2, countdown : 2
Waiting for root system /dev/mmcblk1p2, countdown : 1
Rootfs: /dev/mmcblk0p2
[ 28.215766] /dev/mmcblk0p2: Can't open blockdev
[ 28.223334] /dev/mmcblk0p2: Can't open blockdev
mount: mounting /dev/mmcblk0p2 on /mnt/root failed: No such file or directory
umount: can't unmount /mnt/root: Invalid argument
Dropping to a shell.

/ # [ 32.481996] vcc3v0: disabling
[ 32.485067] vcc5v0: disabling
[ 32.488083] cam-avdd: disabling
[ 32.491268] cam-dvdd: disabling

/ #

[avafinger]

So must be: Waiting for root system /dev/mmcblk2p2

Try to check in the shell.

ls /dev/mmcbl*

[mariusares]

/ # ls /dev/mmc*
/dev/mmcblk2 /dev/mmcblk2boot1 /dev/mmcblk2p2
/dev/mmcblk2boot0 /dev/mmcblk2p1
/ # [ 64.482738] cfg80211: failed to load regulatory.db

i`ll fix it now in few minutes
and the /etc/fstab as well

[avafinger]

we now know ..
root= /dev/mmcblk2p2
fstab must reflect the same.

for the record:
which boot.scr is the correct one?

[mariusares]

[ 2.481578] platform regulatory.0: Direct firmware load for regulatory.db failed with error -2
[ 2.491546] platform regulatory.0: Falling back to sysfs fallback for: regulatory.db
[ 2.492587] No soundcards found.
[ 2.505182] Freeing unused kernel memory: 1024K
[ 2.572998] Run /init as init process
Kernel params: console=ttyS0,115200 earlyprintk rootfstype=ext4 root=/dev/mmcblk2p2 rw rootwait fsck.repair=yes panic=10 no_console_suspend consoleblank=0 drm_leak_fbdev_smem=1
Waiting for root system /dev/mmcblk2p2, countdown : 5
Rootfs: /dev/mmcblk2p2
[ 2.735318] EXT4-fs (mmcblk2p2): bad geometry: block count 1909760 exceeds size of device (1876992 blocks)
mount: mounting /dev/mmcblk2p2 on /mnt/root failed: Invalid argument
umount: can't unmount /mnt/root: Invalid argument
Waiting for root system /dev/mmcblk2p2, countdown : 4
Rootfs: /dev/mmcblk2p2
[ 7.891324] EXT4-fs (mmcblk2p2): bad geometry: block count 1909760 exceeds size of device (1876992 blocks)
mount: mounting /dev/mmcblk2p2 on /mnt/root failed: Invalid argument
umount: can't unmount /mnt/root: Invalid argument
Waiting for root system /dev/mmcblk2p2, countdown : 3
Rootfs: /dev/mmcblk2p2
[ 13.028491] EXT4-fs (mmcblk2p2): bad geometry: block count 1909760 exceeds size of device (1876992 blocks)
mount: mounting /dev/mmcblk2p2 on /mnt/root failed: Invalid argument
umount: can't unmount /mnt/root: Invalid argument

[mariusares]

i`ll try to copy it one more time ... so it is the bpi-m2-zero_boot_1.scr with root=/dev/mmcblk2p2 and /etc/fstab modified right now

[avafinger]

right, did you use the format_mainline.sh /dev/mmcblk2 to burn the eMMC? I think you used dd..

[mariusares]

well i formated and after i used dd

[avafinger]

that's why you get: [ 7.891324] EXT4-fs (mmcblk2p2): bad geometry: block count 1909760 exceeds size of device (1876992 blocks)

[avafinger]

i will redo the scripts with your information and you burn the eMMC.
you can try to fix this using disk while boot from SD CARD.

[mariusares]

so how can i copy from sd card afer format without using dd ?

[avafinger]

I would tar.gz the boot and the rootfs and untar in each partition (eMMC), is faster.

[mariusares]

i resized the partition . working from emmc now ...

[mariusares]

Would you like a working image?

[avafinger]

I don't have the board. Maybe you make a backup of eMMC and announce it on the forum. What is the Ubuntu version?

[mariusares]

is the 16.04 LTE ... is your image actually
root@bpi-m2z:~# uname -a && cat /etc/issue && fdisk -l
Linux bpi-m2z 5.7.6 #1 SMP Sun Jun 28 00:11:55 -03 2020 armv7l armv7l armv7l GNU/Linux
Ubuntu 16.04.4 LTS \n \l

Disk /dev/mmcblk2: 7.3 GiB, 7818182656 bytes, 15269888 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disklabel type: dos
Disk identifier: 0x58b49123

Device Boot Start End Sectors Size Id Type
/dev/mmcblk2p1 49152 253951 204800 100M 83 Linux
/dev/mmcblk2p2 253952 15269886 15015935 7.2G 83 Linux
root@bpi-m2z:~#

[mariusares]

it is strange ... i have resized the partition and i reboot it then worked
now i reboot the system again and i got the same error ...

Waiting for root system /dev/mmcblk2p2, countdown : 3
Rootfs: /dev/mmcblk2p2
[ 12.948746] EXT4-fs (mmcblk2p2): bad geometry: block count 1909760 exceeds size of device (1876991 blocks)
mount: mounting /dev/mmcblk2p2 on /mnt/root failed: Invalid argument
umount: can't unmount /mnt/root: Invalid argument

[avafinger]

I will prepare the scripts late tonight.

[mariusares]

I'll try to setup the partitions manually ...

[avafinger]

Script to format and create partitions (/boot and /rootfs)

• sudo ./format_sd_mainline.sh /dev/mmcblk2 (boot from SD CARD)
• copy /boot from SD CARD to /boot in eMMC
• copy /rootfs from SD CARD to /rootfs in eMMC
• burn the u-boot (the new one)
• copy the correct scr
• change /etc/fstab in eMMC

Make sure the symlinks are corrects

format_sd_mainline.sh.tar.gz

[mariusares]

ok so ... on your script, when you formated the partition you have the syntax
mkfs.ext4 -F -b 4096 -E stride=2,stripe-width=1024 -L boot ${out}1

should be p1 and p2 ...
mkfs.ext4 -F -b 4096 -E stride=2,stripe-width=1024 -L boot ${out}p1

now the partitions can be mounted

[mariusares]

I have an working eMMC image
Unfortunately it is huge and is not easy to upload...
Any way you might think that we can have a smaller image and to expand the fs after installing? What do you think?

[avafinger]

Yes, there are ways to shrink the IMG. I will think one of them. What size did you get?

[mariusares]

Around 7G unzipped ...
I'll zip it when I'll go home
If I'll shrink the partition to 2G let's say, the img would be around that size as well ...
Btw: what kernel version would you recommend ?
The latest 5.7.7 is ok? ... I'm looking for a stable version
Thank you

[avafinger]

• Boot with eMMC and do a:

sudo apt-get clean

• Boot from SD CARD and and mount eMMC (the rootfs in eMMC) and run:

cd /tmp
mkdir -p eMMC
sudo mount -t ext4 /dev/mmcblk2p2 ./eMMC

sudo rm -rf eMMC/home/ubuntu/.cache/*
sudo rm -rf eMMC/home/ubuntu/Downloads/*
sudo rm -rf eMMC/home/ubuntu/.kodi/*
sudo rm -rf eMMC/tmp/*
sudo rm -rf eMMC/tmp/.*
sudo rm -rf eMMC/var/tmp/*
sudo truncate --size 0 eMMC/var/log/wtmp
sudo truncate --size 0 eMMC/var/log/lastlog
sudo truncate --size 0 eMMC/var/log/dmesg 
sudo truncate --size 0 eMMC/var/log/Xorg.0.log.old
sudo truncate --size 0 eMMC/var/log/btmp 
sudo truncate --size 0 eMMC/home/ubuntu/.bash_history 
sudo truncate --size 0 eMMC/root/.bash_history
sudo truncate --size 0 eMMC/var/log/wtmp 
sudo truncate --size 0 eMMC/var/log/btmp 
sudo truncate --size 0 eMMC/var/log/lastlog
sudo truncate --size 0 eMMC/var/log/syslog
sudo truncate --size 0 eMMC/var/log/lightdm/*.log
sudo truncate --size 0 eMMC/var/log/tallylog
sudo truncate --size 0 eMMC/var/log/faillog
sudo truncate --size 0 eMMC/var/log/apt/term.log
sudo truncate --size 0 eMMC/var/log/apt/history.log
sudo rm -rf eMMC/var/backups/*.gz
sudo rm -rf eMMC/home/ubuntu/iperf
sudo rm -rf eMMC/tmp/*
sudo rm -rf eMMC/tmp/.*
sudo rm -rf eMMC/var/tmp/*
sudo rm -rf eMMC/home/adduser.sh
sudo rm -rf eMMC/etc/NetworkManager/system-connections/*
sudo rm -rf eMMC/var/lib/apt/lists/*
sudo rm -rf eMMC/var/cache/apt/archives/*
sudo rm -rf eMMC/var/log/*.1
sudo rm -rf eMMC/var/log/apt/*.log.xz
sudo find eMMC/var/log/journal -name "*.journal"| xargs sudo rm -rf
sudo find eMMC/var/log/journal -name "*.journal~"| xargs sudo rm -rf
sudo find eMMC/var/log/ -name "*.gz"| xargs sudo rm -rf
sudo find eMMC/var/backups/ -name "*.gz"| xargs sudo rm -rf
sudo find eMMC/var/log/ -name "*.log"| xargs sudo truncate --size 0
sudo find eMMC/var/backups/ -name "*.*"| xargs sudo truncate --size 0
sudo find eMMC/var/lib/dhcp/ -name "*.*"| xargs sudo truncate --size 0

Copy the rootfs and Compress it:

tar -cvpzf rootfs_16.04.tar.gz --directory=./eMMC .

unmount eMMC

sudo umount ./eMMC

Do the same for the /boot partition in eMMC

mkdir -p eMMC_boot
tar -cvpzf boot_16.04.tar.gz --directory=./eMMC_boot .
sudo umount ./eMMC_boot

[mariusares]

Ok and you have two zip files ....
Now how many users know how to create the partitions, how to write the bootloader and how to install the files in emmc?
I have the emmc installed blank, this is why I'm trying to make a image
The system is insane fast ...
I'm expecting to be stable too.
You did a great job

[avafinger]

You can shrink rootfs partition to 2.2G (after the clean up described above) and 7zip the /dev/mmblck2 for the users, they just need to dd to /dev/mmcblk2 and resize!

[mariusares]

ok, the large image when is zipped is less than 300MB and it is with full eMMC size and settings ..

[mariusares]

http://forum.banana-pi.org/t/ubuntu-16-04-lts-lite-emmc-image-for-bpi-p2-zero/11289