The 'flannel' meta plugin delegates to other plugins to do the actual
OS-level work. It used the ipam.Exec{Add,Del} procedures for this
delegation, since those do precisely what's needed.
However this is a bit misleading, since the flannel plugin _isn't_
doing this for IPAM, and the ipam.Exec* procedures aren't doing
something specific to IPAM plugins.
So: anticipating that there may be more meta plugins that want to
delegate in the same way, this commit moves generic delegation
procedures to `pkg/invoke`, and makes the `pkg/ipam` procedures (still
used, accurately, in the non-meta plugins) shims.
- Believe we need sudo to create netns
- Use syscall instead of relying on ip netns
- Add sudo to .travis.yml
- Needs more -E
- Revert Godeps GoVersion to 1.4.2
- in travis, test command is run with all necessary env vars
- Loopback plugin only works on 'lo' interface
- Update README, add loopback plugin config
- note script dependency on jq
Signed-off-by: Gabe Rosenhouse <grosenhouse@pivotal.io>
Allow users to tune net network parameters such as somaxconn.
With this patch, users can add a new network configuration:
> {
> "name": "mytuning",
> "type": "tuning",
> "sysctl": {
> "net.core.somaxconn": "500"
> }
> }
The value /proc/sys/net/core/somaxconn will be set to 500 in the network
namespace but will remain unchanged on the host.
Only sysctl parameters that belong to the network subsystem can be
modified.
Related to: https://github.com/coreos/rkt/pull/2140
appc/cni#76 added a "dns" field in the result JSON. But before this
patch, the plugins had no way of knowing which name server to return.
There could be two ways of knowing which name server to return:
1. add it as an extra argument ("CNI_ARGS")
2. add it in the network configuration as a convenience (received via
stdin)
I chose the second way because it is easier. In the case of rkt, it
means the user could just add the DNS name servers in
/etc/rkt/net.d/mynetwork.conf.
In some cases the route deletion would fail due to wrong
scope. It should be NOWHERE when deleting (per iproute2).
This also adds more verbose error messages.
Instead of allocating a /31 for each container,
use the same IP on the host side for all veths.
This is very similar how real point-to-point
devices work (using donor IPs).
This takes some of the machinery from CNI and from the rkt networking
code, and turns it into a library that can be linked into go apps.
Included is an example command-line application that uses the library,
called `cnitool`.
Other headline changes:
* Plugin exec'ing is factored out
The motivation here is to factor out the protocol for invoking
plugins. To that end, a generalisation of the code from api.go and
pkg/plugin/ipam.go goes into pkg/invoke/exec.go.
* Move argument-handling and conf-loading into public API
The fact that the arguments get turned into an environment for the
plugin is incidental to the API; so, provide a way of supplying them
as a struct or saying "just use the same arguments as I got" (the
latter is for IPAM plugins).
Luckily the docs haven't mentioned support for ipMasq for both plugins so far.
Even if anyone has attempted to enable the feature in their configuration files it didn't have the desired effect for the network.
A specific IP can now be requested via the environment variable CNI_ARGS, e.g.
`CNI_ARGS=ip=1.2.3.4`.
The plugin will try to reserve the specified IP.
If this is not successful the execution will fail.
Instead of temp (random) name, the final name (e.g. eth0)
was used during link creation. This would collide on hosts
that already had the an interface with such a name.
The dhcp daemon may be running with a different cwd
and so the netns paths need to be absolute. This patch
also refactors the code to pull out the common, RPC
parts, out into a separate function.
Path rewriting causes too many problems when vendoring
vendored code. When CNI code is vendored into rkt,
godep has problems code already vendored by CNI.
This introduces a notion of a "meta" plugin. A meta plugin
is one that delegates the actual work of setting up the interface
to the main plugin. The meta plugin is used to select and dynamically
configure the main plugin. The sequence of events, is as follows:
Given netconf like:
{
"name": "mynet",
"type": "flannel",
"delegate": {
"type": "bridge"
}
}
flannel fills in values like "mtu", "ipam.subnet" and delegates to
"bridge" main plugin. "bridge" plugin will operate as usual, calling
into ipam module for IP assignment.
Delegate dictionary should not contain "name" field as it will be
filled in by the flannel plugin.
When plugin errors out, it prints out a JSON object to stdout
describing the failure. This object needs to be propagated out
through the plugins and to the container runtime. This change
also adds Print method to both the result and error structs
for easy serialization to stdout.
The plugin binary actually functions in two modes. The first mode
is a regular CNI plugin. The second mode (when stared with "daemon" arg)
runs a DHCP client daemon. When executed as a CNI plugin, it issues
an RPC request to the daemon for actual processing. The daemon is
required since a DHCP lease needs to be maintained by periodically
renewing it. One instance of the daemon can server arbitrary number
of containers/leases.
Add the ipvlan main plugin which is heavily based on the macvlan plugin.
Availabile modes for this plugin are l2 and l3, wheres l2 has the higher
compatibility due to support for multicast and broadcasts. L2 has therefore been
chosen as the default mode.
See the official docs at
https://www.kernel.org/doc/Documentation/networking/ipvlan.txt
for more information.
Fixes #6.
This adds basic plugins.
"main" types: veth, bridge, macvlan
"ipam" type: host-local
The code has been ported over from github.com/coreos/rkt project
and adapted to fit the CNI spec.
