PVCs using the ReadWriteOncePod access mode can only be referenced by a
single pod. When a pod is scheduled that uses a ReadWriteOncePod PVC,
return "Unschedulable" if the PVC is already in-use in the cluster.
To support preemption, the "VolumeRestrictions" scheduler plugin
computes cycle state during the PreFilter phase. This cycle state
contains the number of references to the ReadWriteOncePod PVCs used by
the pod-to-be-scheduled.
During scheduler simulation (AddPod and RemovePod), we add and remove
reference counts from the cycle state if they use any of these
ReadWriteOncePod PVCs.
In the Filter phase, the scheduler checks if there are any PVC reference
conflicts, and returns "Unschedulable" if there is a conflict.
This is a required feature for the ReadWriteOncePod beta. See for more context:
https://github.com/kubernetes/enhancements/tree/master/keps/sig-storage/2485-read-write-once-pod-pv-access-mode#beta
In fact, this actually uses pkg/util/node's GetHostname() but takes
the unit tests from cmd/kubeadm/app/util's private fork of that
function since they were more extensive. (Of course the fact that
kubeadm had a private fork of this function is a strong argument for
moving it to component-helpers.)
When a block device, say /dev/sdc, is unexpectedly disconnected from a node,
the corresponding backing file path found at /sys/block/loop*/backing_file gets
a "(deleted)" suffix. This patch trims that suffix out, allowing the Kubelet to
unmount the volume correctly.
This fixes the following warning (error?) in the apiserver:
E0126 18:10:38.665239 16370 fieldmanager.go:210] "[SHOULD NOT HAPPEN] failed to update managedFields" err="failed to convert new object (test/claim-84; resource.k8s.io/v1alpha1, Kind=ResourceClaim) to smd typed: .status.reservedFor: element 0: associative list without keys has an element that's a map type" VersionKind="/, Kind=" namespace="test" name="claim-84"
The root cause is the same as in e50e8a0c91:
nothing in Kubernetes outright complains about a list of items where the item
type is comparable in Go, but not a simple type. This nonetheless isn't
supposed to be done in the API and can causes problems elsewhere.
For the ReservedFor field, everything seems to work okay except for the
warning. However, it's better to follow conventions and use a map. This is
possible in this case because UID is guaranteed to be a unique key.
Validation is now stricter than before, which is a good thing: previously,
two entries with the same UID were allowed as long as some other field was
different, which wasn't a situation that should have been allowed.
The ClusterIP allocator tries to reserve on part of the ServiceCIDR
to allocate static IPs to the Services.
The heuristic of the allocator to obtain the offset was taking into
account the whole range size, not the IPs available in the range, the
subnet address and the broadcast address for IPv4 are not available.
This caused that for CIDRs with 16 hosts, /28 for IPv4 and /124 for
IPv6, the offset calculated was higher than the max number of available
addresses on the allocator, causing this to panic.
Change-Id: I6c6f527b0a600b3612be37769e405b8fb3dd33a8
ContainsIPv4Loopback() claimed that "::/0" contains IPv4 loopback IPs
(on the theory that listening on "::/0" will listen on "0.0.0.0/0" as
well and thus include IPv4 loopback). But its sole caller (the
iptables proxier) doesn't use listen() to accept connections, so this
theory was completely mistaken; if you passed, eg,
`--nodeport-addresses 192.168.0.0/0,::/0`, then it would not create
any rule that accepted nodeport connections on 127.0.0.1, but it would
nonetheless end up setting route_localnet=1 because
ContainsIPv4Loopback() claimed it needed to. Fix this.
Add names to the tests and use t.Run() (rather than having them just
be numbered, with number 9 mistakenly being used twice thus throwing
off all the later numbers...)
Remove unnecessary FakeNetwork element from the testCases struct since
it's always the same. Remove the expectedErr value since a non-nil
error is expected if and only if the returned set is nil, and there's
no reason to test the exact text of the error message.
Fix weird IPv6 subnet sizes.
Change the dual-stack tests to (a) actually have dual-stack interface
addrs, and (b) use a routable IPv6 address, not just localhost (given
that we never actually want to use IPv6 localhost for nodeports).
