*: recipe for running acbuild in container

[jonboulle]

We should have acbuild packaged in an ACI and then be able to invoke it using any appc runtime, e.g. rkt. I expect this would just mount in the user's project/asset directly to a known location (/data or whatever) and then run the script they pass to it.

For example with rkt this might look like:

$ ls
app.js
build-nodejs.sh
$ rkt run --volume data,kind=host,source=$(pwd) appc.io/acbuild ./build-nodejs.sh

Where "data" would be defined as a mountpoint in the appc.io/acbuild image. Then this would output the ACI in the same directory.

$ ls
app.js
build-nodejs.sh
nodejs-latest-linux-amd64.aci

[cgonyeo]

In a fedora 22 container:

[root@rkt-a29fb369-a1dd-498d-863f-5de4eb5fe7f7 /]# systemd-nspawn
Not running on a systemd system.

Perhaps once alternate execution environments is implemented this will be possible, but it doesn't look like this is feasible with the current state of acbuild.

[jonboulle]

@dgonyeo how about a container based on CoreOS or something to pick up a more modern systemd-nspawn? That check was removed a while ago: https://github.com/systemd/systemd/commit/4f923a1984476de3441922ee5bf7102ebdd250ef

[cgonyeo]

I made a container out of coreos_developer_container.bin.bz2 from http://alpha.release.core-os.net/amd64-usr/current/, but when I attempt to run the nginx example in it I get the following:

root@rkt-98235c83-868a-48a4-8d17-8ce7dd5da102 ~ # acbuild begin
root@rkt-98235c83-868a-48a4-8d17-8ce7dd5da102 ~ # acbuild dep add quay.io/coreos/alpine-sh
root@rkt-98235c83-868a-48a4-8d17-8ce7dd5da102 ~ # acbuild run -- apk update
Downloading quay.io/coreos/alpine-sh: [========================] 2.65 MB/2.65 MB
Failed to open system bus: No such file or directory
Failed to create directory /root/.acbuild/target/sys/fs/selinux: Read-only file system
Failed to create directory /root/.acbuild/target/sys/fs/selinux: Read-only file system
/etc/localtime is not a symlink, not updating container timezone.
Failed to copy /etc/resolv.conf to /root/.acbuild/target/etc/resolv.conf: No such device or address
Attempted to remove disk file system, and we can't allow that.
run: exit status 1

Any clue what's going on here? I can't figure out why it would be a read-only file system.

[jonboulle]

Weird. Can you narrow it down to an explicit systemd nspawn invocation case to reproduce?

On Tue, Nov 3, 2015, 19:40 Derek Gonyeo [email protected] wrote:

I made a container out of coreos_developer_container.bin.bz2 from http://alpha.release.core-os.net/amd64-usr/current/, but when I attempt to run the nginx example in it I get the following:

root@rkt-98235c83-868a-48a4-8d17-8ce7dd5da102 ~ # acbuild begin root@rkt-98235c83-868a-48a4-8d17-8ce7dd5da102 ~ # acbuild dep add quay.io/coreos/alpine-sh root@rkt-98235c83-868a-48a4-8d17-8ce7dd5da102 ~ # acbuild run -- apk update Downloading quay.io/coreos/alpine-sh: [========================] 2.65 MB/2.65 MB Failed to open system bus: No such file or directory Failed to create directory /root/.acbuild/target/sys/fs/selinux: Read-only file system Failed to create directory /root/.acbuild/target/sys/fs/selinux: Read-only file system /etc/localtime is not a symlink, not updating container timezone. Failed to copy /etc/resolv.conf to /root/.acbuild/target/etc/resolv.conf: No such device or address Attempted to remove disk file system, and we can't allow that. run: exit status 1

Any clue what's going on here? I can't figure out why it would be a read-only file system.

— Reply to this email directly or view it on GitHub https://github.com/appc/acbuild/issues/86#issuecomment-153449319.

[cgonyeo]

Yup. The directory I'm pointing systemd-nspawn at here is the rootfs from quay.io/coreos/alpine-sh.

root@rkt-98235c83-868a-48a4-8d17-8ce7dd5da102 ~ # systemd-nspawn -D ./rootfs/ /sbin/apk update   
Spawning container rootfs on /root/rootfs.
Press ^] three times within 1s to kill container.
Failed to open system bus: No such file or directory
Failed to create directory /root/rootfs/sys/fs/selinux: Read-only file system
Failed to create directory /root/rootfs/sys/fs/selinux: Read-only file system
/etc/localtime is not a symlink, not updating container timezone.
Attempted to remove disk file system, and we can't allow that.

[cgonyeo]

I just tried this in an ACI made out of gentoo's stage 3, and get a different, but similar output to when it was in the coreos ACI.

root@rkt-983d74af-c0f5-4c36-a39f-4d0e2350a9e2 ~ # systemd-nspawn -D ./rootfs/ /sbin/apk update
Spawning container rootfs on /root/rootfs.
Press ^] three times within 1s to kill container.
Failed to open system bus: No such file or directory
/etc/localtime is not a symlink, not updating container timezone.
Parent died too earlyAttempted to remove disk file system, and we can't allow that.

[jonboulle]

Any luck troubleshooting this further? perhaps ping upstream systemd?

[chancez]

You might try invoking nspawn with --boot so it starts an init. On Tue, Nov 10, 2015 at 6:17 PM Jonathan Boulle [email protected] wrote:

Any luck troubleshooting this further? perhaps ping upstream systemd?

— Reply to this email directly or view it on GitHub https://github.com/appc/acbuild/issues/86#issuecomment-155633035.

[blalor]

I really want this. Not sure how this'll be solved given the need for OverlayFS… Is it even possible to interact with kernel-level stuff like that in an ACE container?