Automatic merge from submit-queue (batch tested with PRs 45040, 48960)
Do not generate warning event on dns search deduplication
In the case that the node is able to use the cluster DNS, `cluster.local` will already be in the node search domains in `/etc/resolv.conf`. The kubelet then parses `/etc/resolv.conf` on the node and combines it with $namespace.svc.$clusterDomain, svc.$clusterDomain, and $clusterDomain to create the pod DNS search domains. clusterDomain is `cluster.local` by default. This causes the code to generate a Warning event visible to the user for _every_ pod:
```
Warning DNSSearchForming Found and omitted duplicated dns domain in host search line: 'cluster.local' during merging with cluster dns domains
```
This is really overkill. IMHO, this should be done in the background with no user level notification or logging at all.
xref https://bugzilla.redhat.com/show_bug.cgi?id=1471198
@derekwaynecarr @eparis @vefimova
Since v1.5 and the removal of --configure-cbr0:
0800df74ab "Remove the legacy networking mode --configure-cbr0"
kubelet hasn't done any shaping operations internally. They
have all been delegated to network plugins like kubenet or
external CNI plugins. But some shaping code was still left
in kubelet, so remove it now that it's unused.
Automatic merge from submit-queue
resolv.conf nameserver line has only one entry, ignore trailing garbage
**What this PR does / why we need it**:
Per the resolv.conf man page "name servers may be listed, one per keyword." Some tools such as udhcpc take advantage of this to append comments to nameserver entries. For example: `nameserver 8.8.8.8 # eth0`. This updates the resolv.conf parser to ignore trailing garbage on nameserver lines.
**Release note**:
NONE
Automatic merge from submit-queue (batch tested with PRs 37228, 40146, 40075, 38789, 40189)
Cleanup temp dirs
So funny story my /tmp ran out of space running the unit tests so I am cleaning up all the temp dirs we create.
- exclude duplicates while merging of host's and dns' search lines to form pod's one
- truncate pod's search line if it exceeds resolver limits: is > 255 chars and containes > 6 searches
- monitoring the resolv.conf file which is used by kubelet (set thru --resolv-conf="") and logging and eventing if search line in it consists of more than 3 entries
(or 6 if Cluster Domain is set) or its lenght is > 255 chars
- logging and eventing when a pod's search line is > 255 chars or containes > 6 searches during forming
Fixes#29270
Kubernetes Submit Queue