Ubuntu Snaps inside LXC container on Proxmox

U

UrkoM

New Member
Oct 15, 2014
17
0
1
Hi,
I am trying to test Snap applications inside an Ubuntu 16.04 LXC container in Proxmox, and I am running into problems.
I found this link:
https://stgraber.org/2017/01/31/ubuntu-core-in-lxd-containers/
And it seems snapd needs "unprivileged FUSE mounts and AppArmor namespacing and stacking"'.

Am I trying the impossible here? Has anyone looked into this or has any idea if/when this will be possible on Proxmox?

I could run Ubuntu 16.04 as QEMU VM, but I really like the (maybe theoretical in this case?) performance advantage of LXC for this.

Thanks!
 
Trying to install on PVE5.2-1 on a ubuntu 18.04 LXC and after the install i got some message about kernel needing AppArmor 2.4 compatibility patch or something like that.
I never was able to found a solution do snaps on LXC. I'm running VMs for services like, Rocket.Chat, Wekan, and so on.
 
I was trying to install nextcloud as snap inside an ubuntu xenial container when I faced with this problem. Is my understanding that the problem is related to missing features in the PVE Kernel.

Is this a problem with Proxmox? or the packaged containers? Is this a bug?
 
  • Like
Reactions: dbayer
davidg1982 said:
Is there something easier?
Click to expand...
You maybe lucky, this got applied :)
With the pve-container package in version 2.0-28 (or newer) you should be able to set the 'mount' and 'nesting' features and it should work.

This is currently not exposed over the GUI, but you can create a CT as usual there and then open a shell on PVE and do something alike:
Code: 
pct set VMID --features mount=1,nesting=1
Edit, above did not work with mount, as this needs a list on accepted file systems, e.g.:
Code: 
pct set VMID --features mount=fuse;nfs,nesting=1
on the stopped CT and then, on the next start it should work.
 
Last edited:
t.lamprecht said:
You maybe lucky, this got applied :)
With the pve-container package in version 2.0-28 (or newer) you should be able to set the 'mount' and 'nesting' features and it should work.

This is currently not exposed over the GUI, but you can create a CT as usual there and then open a shell on PVE and do something alike:
Code: 
pct set VMID --features mount=1,nesting=1
on the stopped CT and then, on the next start it should work.
Click to expand...
That's helpful. Thank you.
Is pve-container version 2.0-28 in the test repository? Because I am running pve-container 2.0-25 and that seems to be the only version available. I have this in my source.list:
Code: 
deb http://enterprise.proxmox.com/debian/pve stretch pve-enterprise
 
davidg1982 said:
That's helpful. Thank you.
Is pve-container version 2.0-28 in the test repository? Because I am running pve-container 2.0-25 and that seems to be the only version available. I have this in my source.list:
Code: 
deb http://enterprise.proxmox.com/debian/pve stretch pve-enterprise
Click to expand...

Its in the repository but you have a typo in your sources.list entry (you need https instead of http):

> deb https://enterprise.proxmox.com/debian/pve stretch pve-enterprise
 
I must be doing something incorrectly.
Code: 
david@proxmox:~$ sudo apt update
Ign:1 http://ftp.us.debian.org/debian stable InRelease
Hit:2 http://repo.zabbix.com/zabbix/3.4/debian stretch InRelease                     
Hit:3 http://security.debian.org stable/updates InRelease                           
Hit:4 http://ftp.us.debian.org/debian stable Release                   
Get:5 https://enterprise.proxmox.com/debian/pve stretch InRelease [2,081 B]
Hit:5 https://enterprise.proxmox.com/debian/pve stretch InRelease
Reading package lists... Done                         
Building dependency tree     
Reading state information... Done
All packages are up to date.
david@proxmox:~$ apt-cache policy pve-container
pve-container:
  Installed: 2.0-25
  Candidate: 2.0-25
  Version table:
 *** 2.0-25 100
        100 /var/lib/dpkg/status
david@proxmox:~$

Here is the rest of my pveversion -v
Code: 
proxmox-ve: 5.2-2 (running kernel: 4.15.18-2-pve)
pve-manager: 5.2-7 (running version: 5.2-7/8d88e66a)
pve-kernel-4.15: 5.2-5
pve-kernel-4.15.18-2-pve: 4.15.18-20
pve-kernel-4.15.17-1-pve: 4.15.17-9
pve-kernel-4.13.13-5-pve: 4.13.13-38
pve-kernel-4.4.98-4-pve: 4.4.98-104
pve-kernel-4.4.79-1-pve: 4.4.79-95
pve-kernel-4.4.59-1-pve: 4.4.59-87
corosync: 2.4.2-pve5
criu: 2.11.1-1~bpo90
glusterfs-client: 3.8.8-1
ksm-control-daemon: 1.2-2
libjs-extjs: 6.0.1-2
libpve-access-control: 5.0-8
libpve-apiclient-perl: 2.0-5
libpve-common-perl: 5.0-38
libpve-guest-common-perl: 2.0-17
libpve-http-server-perl: 2.0-10
libpve-storage-perl: 5.0-24
libqb0: 1.0.1-1
lvm2: 2.02.168-pve6
lxc-pve: 3.0.2+pve1-1
lxcfs: 3.0.0-1
novnc-pve: 1.0.0-2
openvswitch-switch: 2.6.2~pre+git20161223-3
proxmox-widget-toolkit: 1.0-19
pve-cluster: 5.0-29
pve-container: 2.0-25
pve-docs: 5.2-8
pve-firewall: 3.0-13
pve-firmware: 2.0-5
pve-ha-manager: 2.0-5
pve-i18n: 1.0-6
pve-libspice-server1: 0.12.8-3
pve-qemu-kvm: 2.11.2-1
pve-xtermjs: 1.0-5
pve-zsync: 1.6-16
qemu-server: 5.0-32
smartmontools: 6.5+svn4324-1
spiceterm: 3.0-5
vncterm: 1.5-3
 
I'm on PVE 5.2-11 with pve-container 2.0.29 and I'm must be missing something.
On a Ubuntu 18.04 container and the nesting and mouting features enabled.
Installed snapd and bam:

-- Unit snapd.service has finished shutting down.
Nov 27 15:50:31 gsm systemd[1]: snapd.service: Start request repeated too quickly.
Nov 27 15:50:31 gsm systemd[1]: snapd.service: Failed with result 'exit-code'.
Nov 27 15:50:31 gsm systemd[1]: Failed to start Snappy daemon.
-- Subject: Unit snapd.service has failed
-- Defined-By: systemd
-- Support: http://www.ubuntu.com/support
--
-- Unit snapd.service has failed.
--
-- The result is RESULT.
Nov 27 15:50:31 gsm systemd[1]: snapd.socket: Failed with result 'service-start-limit-hit'.
Nov 27 15:50:35 gsm snap[2814]: error: cannot communicate with server: Get http://localhost/v2/snaps/system/conf?keys=seed.loaded: dial unix /run/snapd.socket: connect: co
Nov 27 15:50:35 gsm systemd[1]: snapd.seeded.service: Main process exited, code=exited, status=1/FAILURE
Nov 27 15:50:35 gsm systemd[1]: snapd.seeded.service: Failed with result 'exit-code'.
Nov 27 15:50:35 gsm systemd[1]: Failed to start Wait until snapd is fully seeded.
 
Snap requires a bit more work. There may soon be a 'fuse' flag for the features option, but fuse can be dangerous. For now you have to do this:

- For unprivileged containers:
1) Put this in /etc/pve/lxc/$vmid.conf:
Code: 
...
features: mount=fuse,nesting=1
lxc.mount.entry = /dev/fuse dev/fuse none bind,create=file 0 0
2) Inside the container: `apt install squashfuse`

- For privileged containers, also add:
Code: 
...
# EDIT:
# We need to allow apparmor administration, by default mac_admin is dropped for privileged containers.
# Note that you do not want this for un-trusted containers...
lxc.cap.drop =
lxc.cap.drop = mac_override sys_time sys_module sys_rawio
Alternatively to squashfuse, privileged containers could use loop devices, but I wouldn't recommend it...


Note that enabling `fuse` in a container does not play well with backups, or anything that causes an `lxc-freeze` command to be executed on the container, as this can cause deadlocks in the kernel...
 
Last edited:
  • Like
Reactions: clipz98
Hi Wolfgang,

Is there any progress on integrating snap into LXC containers? So far, if I'd like to e.g. install wekan, I'll need a VM which is not my favourite way to run Linux software on Proxmox.

Any suggestions?
 
Hey team, just wanted to say I've got wekan running in an LXC container, so I think this thread has maybe come full loop. I don't actually have to hand-modify the conf either, just go to the container > options > features > tick FUSE and Nesting, restart container, snapd install wekan fails first time with errors:

Code: 
error: cannot perform the following tasks:
- Setup snap "core" (8935) security profiles (cannot setup udev for snap "core": cannot reload udev rules: exit status 2
udev output:
)
- Setup snap "core" (8935) security profiles (cannot reload udev rules: exit status 2
udev output:
)

but then just re-running the exact same command, it completes successfully and works.
 
  • Like
Reactions: alexstaeding and MuttleyDoSomething
Hi,
Here when I try
Code: 
snap install wekan
I always have an error :

Code: 
error: system does not fully support snapd: cannot mount squashfs image using "fuse.squashfuse":
       mount: /tmp/sanity-mountpoint-494747820: wrong fs type, bad option, bad superblock on
       /tmp/sanity-squashfs-152452673, missing codepage or helper program, or other error.

I tried both of solutions : manually edit config file / just tick options, but the problem is always the same, it does not work :(
 
  • Like
Reactions: networ
I'm successfully running Wekan via Snap on an Ubuntu 19.04 container (which was now upgraded to 19.10).

These are my LXC settings:

Code: 
arch: amd64
cores: 4
features: keyctl=1,nesting=1,fuse=1
hookscript: local:snippets/pve-hook
hostname: projekte
memory: 2048
net0: name=eth0,bridge=vmbr0,firewall=1,gw=192.168.100.1,hwaddr=xx,ip=xx/24,type=veth
onboot: 1
ostype: ubuntu
rootfs: rpool:subvol-121-disk-0,acl=1,size=32G
swap: 512
unprivileged: 1
 
  • Like
Reactions: CanadaGuy and datdenkikniet
You must log in or register to reply here.

About

The Proxmox community has been around for many years and offers help and support for Proxmox VE, Proxmox Backup Server, and Proxmox Mail Gateway.
We think our community is one of the best thanks to people like you!

Quick Navigation

Home Get Subscription Wiki Downloads Proxmox Customer Portal About

Get your subscription!

The Proxmox team works very hard to make sure you are running the best software and getting stable updates and security enhancements, as well as quick enterprise support. Tens of thousands of happy customers have a Proxmox subscription. Get yours easily in our online shop.

Buy now!
Community platform by XenForo® © 2010-2024 XenForo Ltd.
Top Bottom