There are two main goals for this change.
1. Fix the naming scheme in kubelet so that it accepts DNS subdomain
name/namespaces correctly (#4920). The design is discussed in #3453.
2. Prepare for syncing the static pods back to the apiserver(#4090). This
includes
- Eliminate the source component in the internal full pod name (#4922). Pods
no longer need sources as they will all be sync'd via apiserver.
- Changing the naming scheme for the static (file-, http-, and etcd-based)
pods such that they are distinguishable when syncing back to the apiserver.
The changes includes:
* name = <pod.Name>-<hostname>
* namespace = <cluster_namespace> (i.e. "default" for now).
* container_name = k8s_<contianer_name>.<hash_of_container>_<pod_name>_<namespace>_<uid>_<random>
Note that this is not backward-compatible, meaning the kubelet won't recognize
existing running containers using the old naming scheme.
Setting the oom_score_adj of the PID of the POD container to -100 which is less
than the default of 0. This ensures that this PID is the last OOM victim
chosen by the kernel.
Fixes#3067.
This should only have been triggered by tests, and those should now be fixed.
I tested by calling panic() if UID was blank in BuildDockerName() or if number
of fields was < 5 in ParseDockerName(). All errors were fixed.
There are three values that uniquely identify a pod on a host -
the configuration source (etcd, file, http), the pod name, and the
pod namespace. This change ensures that configuration properly
makes those names unique by changing podFullName to contain both
name (currently ID in v1beta1, Name in v1beta3) and namespace.
The Kubelet does not properly handle information requests for
pods not in the default namespace at this time.
Wojciech Tyczynski