run Ubuntu Core(snappy) under KVM

Here are logs when running Ubuntu Core snappy within KVM.

Reference

https://developer.ubuntu.com/en/snappy/start/using-snappy/

download a snappy image and run that image under KVM.

root@ubuntu:~# wget http://releases.ubuntu.com/15.04/ubuntu-15.04-snappy-amd64-generic.img.xz root@ubuntu:~# unxz ubuntu-15.04-snappy-amd64-generic.img.xz root@ubuntu:~# qemu-system-x86_64 --nographic ubuntu-15.04-snappy-amd64-generic.img --enable-kvm -m 512

access to the snappy.

username : ubuntu

credentials : ubuntu

Ubuntu 15.04 localhost.localdomain ttyS0 localhost login: ubuntu Password: (amd64)ubuntu@localhost:~$ sudo su - (amd64)root@localhost:~# (amd64)root@localhost:~# snappy info release: ubuntu-core/15.04/stable architecture: amd64 frameworks: webdm.canonical apps: (amd64)root@localhost:~# snappy list -v Name          Date       Version Developer   ubuntu-core   2016-01-20 13      ubuntu*     webdm         2016-01-20 0.11    canonical* generic-amd64 2016-01-20 1.4     canonical*

install frameworks, “docker”.

You can not use apt-get.

When installing frameworks/apps on Ubuntu Core, you need to install those via snappy command.

(amd64)root@localhost:~# snappy install docker Installing docker Starting download of docker 8.36 MB / 8.36 MB [========================================] 100.00 % 1.28 MB/s Done Starting download of icon for package 21.58 KB / 21.58 KB [=====================================] 100.00 % 73.16 KB/s Done Name          Date       Version   Developer ubuntu-core   2016-01-20 13        ubuntu     docker        2016-02-12 1.6.2.005 canonical webdm         2016-01-20 0.11      canonical generic-amd64 2016-01-20 1.4       canonical (amd64)root@localhost:~# (amd64)root@localhost:~# snappy info release: ubuntu-core/15.04/stable architecture: amd64 frameworks: docker.canonical, webdm.canonical apps:

install an application, ‘hello-world’ via snappy.

(amd64)root@localhost:~# snappy install hello-world Installing hello-world Starting download of hello-world (amd64)root@localhost:~# snappy info release: ubuntu-core/15.04/stable architecture: amd64 frameworks: docker.canonical, webdm.canonical apps: hello-world.canonical

look at /dev/sda

(amd64)root@localhost:~# parted /dev/sda print Model: ATA QEMU HARDDISK (scsi) Disk /dev/sda: 3900MB Sector size (logical/physical): 512B/512B Partition Table: gpt Disk Flags: Number  Start   End     Size    File system  Name         Flags 1      4194kB  8389kB  4194kB               grub         bios_grub 2      8389kB  75.5MB  67.1MB  fat32        system-boot  boot, esp 3      75.5MB  1149MB  1074MB  ext4         system-a 4      1149MB  2223MB  1074MB  ext4         system-b 5      2223MB  3899MB  1676MB  ext4         writable (amd64)root@localhost:~# df -h Filesystem      Size  Used Avail Use% Mounted on udev            237M     0  237M   0% /dev tmpfs            49M  4.7M   45M  10% /run /dev/sda3       976M  623M  287M  69% / /dev/sda5       1.6G   93M  1.4G   7% /writable tmpfs           245M  4.0K  245M   1% /etc/fstab tmpfs           245M     0  245M   0% /dev/shm tmpfs           5.0M     0  5.0M   0% /run/lock tmpfs           245M     0  245M   0% /sys/fs/cgroup tmpfs           245M     0  245M   0% /var/lib/sudo tmpfs           245M     0  245M   0% /tmp tmpfs           245M     0  245M   0% /mnt /dev/sda4       976M  1.3M  908M   1% /writable/cache/system /dev/sda2        63M   52M   12M  82% /boot/efi tmpfs            49M     0   49M   0% /run/user/1000

system-a : for ubuntu core

system-b : for ubuntu core

writable : for apps and frameworks

When upgrading Ubuntu Core, install new Core images into /dev/sda4(system-b) instead of applying updates to /dev/sda3 and boot /dev/sda4(system-b).

apps and frameworks are installed under writable partition called ‘writable(/dev/sda5)’

(amd64)root@localhost:~# ls -l /apps/ total 16 drwxr-xr-x 2 root ubuntu 4096 Feb 12 03:20 bin drwxr-xr-x 3 root root   4096 Feb 12 03:05 docker drwxr-xr-x 3 root root   4096 Feb 12 03:19 hello-world.canonical drwxr-xr-x 3 root ubuntu 4096 Jan 20 07:02 webdm (amd64)root@localhost:~# ls -l /apps/docker/ total 4 drwxr-xr-x 6 clickpkg clickpkg 4096 Feb 12 03:05 1.6.2.005 lrwxrwxrwx 1 root     root        9 Feb 12 03:05 current -> 1.6.2.005 (amd64)root@localhost:~# ls -l /apps/hello-world.canonical/ total 4 drwxr-xr-x 5 clickpkg clickpkg 4096 Feb 12 03:19 1.0.18 lrwxrwxrwx 1 root     root        6 Feb 12 06:01 current -> 1.0.18