Add a --readonly flag to allow the container's root filesystem to be
mounted as readonly. This can be used in combination with volumes to
force a container's process to only write to locations that will be
persisted. This is useful in many cases where the admin controls where
they would like developers to write files and error on any other
locations.
Closes#7923Closes#8752
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
We want to be able to use container without the PID namespace. We basically
want containers that can manage the host os, which I call Super Privileged
Containers. We eventually would like to get to the point where the only
namespace we use is the MNT namespace to bring the Apps userspace with it.
By eliminating the PID namespace we can get better communication between the
host and the clients and potentially tools like strace and gdb become easier
to use. We also see tools like libvirtd running within a container telling
systemd to place a VM in a particular cgroup, we need to have communications of the PID.
I don't see us needing to share PID namespaces between containers, since this
is really what docker exec does.
So currently I see us just needing docker run --pid=host
Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
This commit contains changes for docker:
* user.GetGroupFile to user.GetGroupPath docker/libcontainer#301
* Add systemd support for OOM docker/libcontainer#307
* Support for custom namespaces docker/libcontainer#279, docker/libcontainer#312
* Fixes#9699docker/libcontainer#308
Signed-off-by: Alexander Morozov <lk4d4@docker.com>
Some workloads rely on IPC for communications with other processes. We
would like to split workloads between two container but still allow them
to communicate though shared IPC.
This patch mimics the --net code to allow --ipc=host to not split off
the IPC Namespace. ipc=container:CONTAINERID to share ipc between containers
If you share IPC between containers, then you need to make sure SELinux labels
match.
Docker-DCO-1.1-Signed-off-by: Dan Walsh <dwalsh@redhat.com> (github: rhatdan)
Since the containers can handle the out of memory kernel kills gracefully, docker
will only provide out of memory information as an additional metadata as part of
container status.
Docker-DCO-1.1-Signed-off-by: Vishnu Kannan <vishnuk@google.com> (github: vishh)
We removed the syncpipe package and replaced it with specific calls to
create a new *os.File from a specified fd passed to the process. This
reduced code and an extra object to manage the container's init
lifecycle.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Right now, MAC addresses are randomly generated by the kernel when
creating the veth interfaces.
This causes different issues related to ARP, such as #4581, #5737 and #8269.
This change adds support for consistent MAC addresses, guaranteeing that
an IP address will always end up with the same MAC address, no matter
what.
Since IP addresses are already guaranteed to be unique by the
IPAllocator, MAC addresses will inherit this property as well for free.
Consistent mac addresses is also a requirement for stable networking (#8297)
since re-using the same IP address on a different MAC address triggers the ARP
issue.
Finally, this change makes the MAC address accessible through docker
inspect, which fixes#4033.
Signed-off-by: Andrea Luzzardi <aluzzardi@gmail.com>
This also removes dead code in the native driver for a past feature that
was never fully implemented.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
This changes the way the exec drivers work by not specifing a -driver
flag on reexec. For each of the exec drivers they register their own
functions that will be matched aginst the argv 0 on exec and called if
they match.
This also allows any functionality to be added to docker so that the
binary can be reexec'd and any type of function can be called. I moved
the flag parsing on docker exec to the specific initializers so that the
implementations do not bleed into one another. This also allows for
more flexability within reexec initializers to specify their own flags
and options.
Signed-off-by: Michael Crosby <michael@docker.com>
lxc is special in that we cannot create the master outside of the
container without opening the slave because we have nothing to provide to the
cmd. We have to open both then do the crazy setup on command right now instead of
passing the console path to lxc and telling it to open up that console. we save a couple of
openfiles in the native driver because we can do this.
Docker-DCO-1.1-Signed-off-by: Michael Crosby <michael@docker.com> (github: crosbymichael)