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Delete stale UDP conntrack entries that use hostPort
**What this PR does / why we need it**:
This PR introduces a change to delete stale conntrack entries for UDP connections, specifically for udp connections that use hostPort. When the pod listening on that udp port get updated/restarted(and gets a new ip address), these entries need to be flushed so that ongoing udp connections can recover once the pod is back and the new iptables rules have been installed.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#59033
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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Don't create no-op iptables rules for services with no endpoints
Currently for all services we create `-t nat -A KUBE-SERVICES` rules that match the destination IPs (ClusterIP, ExternalIP, NodePort IPs, etc) and then jump to the appropriate `KUBE-SVC-XXXXXX` chain. But if the service has no endpoints then the `KUBE-SVC-XXXXXX` chain will be empty and so nothing happens except that we wasted time (a) forcing iptables-restore to parse the match rules, and (b) forcing the kernel to test matches that aren't going to have any effect.
This PR gets rid of the match rules in this case. Which is to say, it changes things so that every incoming service packet is matched *either* by nat rules to rewrite it *or* by filter rules to ICMP reject it, but not both. (Actually, that's not quite true: there are no filter rules to reject Ingress-addressed packets, and I *think* that's a bug?)
I also got rid of some comments that seemed redundant.
The patch is mostly reindentation, so best viewed with `diff -w`.
Partial fix for #56842 / Related to #56164 (which it conflicts with but I'll fix that after one or the other merges).
**Release note**:
```release-note
Removed some redundant rules created by the iptables proxier, to improve performance on systems with very many services.
```
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Migrate FeatureGates type of kube-proxy from string to map[string]bool
**What this PR does / why we need it**:
Migration of FeatureGates type. This is a follow-up of #53025.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
ref: #53025https://github.com/kubernetes/kubernetes/pull/57754#discussion_r160023416
**Special notes for your reviewer**:
/cc @luxas @mtaufen @ncdc
**Release note**:
```release-note
action required: kube-proxy: feature gates are now specified as a map when provided via a JSON or YAML KubeProxyConfiguration, rather than as a string of key-value pairs.
```
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Split KUBE-SERVICES chain to re-shrink the INPUT chain
**What this PR does / why we need it**:
#43972 added an iptables rule "`-A INPUT -j KUBE-SERVICES`" to make NodePort ICMP rejection work. (Previously the KUBE-SERVICES chain was only run from OUTPUT, not INPUT.) #44547 extended that patch for ExternalIP rejection as well.
However, the KUBE-SERVICES chain may potentially have a very large number of ICMP reject rules for plain ClusterIP services (the ones that get run from OUTPUT), and it seems that for some reason the kernel is much more sensitive to the length of the INPUT chain than it is to the length of the OUTPUT chain. So a node that worked fine with kube 1.6 (when KUBE-SERVICES was only run from OUTPUT) might fall over with kube 1.7 (with KUBE-SERVICES being run from both INPUT and OUTPUT).
(Specifically, a node with about 5000 ClusterIP reject rules that ran fine with OpenShift 3.6 [kube 1.6] slowed almost to a complete halt with OpenShift 3.7 [kube 1.7].)
This PR fixes things by splitting out the "new" part of KUBE-SERVICES (NodePort and ExternalIP reject rules) into a separate KUBE-EXTERNAL-SERVICES chain run from INPUT, and moves KUBE-SERVICES back to being only run from OUTPUT. (So, yes, this assumes that you don't have 5000 NodePort/ExternalIP services, but, if you do, there's not much we can do, since those rules *have* to be run on the INPUT side.)
Oh, and I left in the code to clean up the "`-A INPUT -j KUBE-SERVICES`" rule even though we don't generate it any more, so it gets fixed on upgrade.
**Release note**:
```release-note
Reorganized iptables rules to fix a performance regression on clusters with thousands of services.
```
@kubernetes/sig-network-bugs @kubernetes/rh-networking
There's a disconnect between 12d4eac038
and the earlier a6af827898. One says
KUBEPROXY_MODE and another says KUBE_PROXY_MODE. Let's just pick one.
Currently we fail with the following error:
hack/local-up-cluster.sh: line 808: KUBEPROXY_MODE: unbound variable
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Refactor kube-proxy service/endpoints update so that can be consumed among different proxiers
**What this PR does / why we need it**:
There are huge duplication among different proxiers. For example, the service/endpoints list/watch part in iptables, ipvs and windows kernel mode(to be get in soon).
I think the more places this is replicated the harder it becomes to keep correct. We may need to refactor it and let different proxiers consume the same code.
**Which issue this PR fixes**:
fixes#52464
**Special notes for your reviewer**:
* This refactor reduces **500** Lines in iptables proxy, so it will reduce **500*N**(number of proxiers) lines in total. People no need to care the service/endpoints update logic any more and can be more focus on proxy logic.
* I would like to do the following things in follow-ups:
1. rsync it to ipvs proxier
2. rsync it to winkernel proxier
**Release note**:
```release-note
Refactor kube-proxy service/endpoints update so that can be consumed among different proxiers
```
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fix all the typos across the project
**What this PR does / why we need it**:
There are lots of typos across the project. We should avoid small PRs on fixing those annoying typos, which is time-consuming and low efficient.
This PR does fix all the typos across the project currently. And with #59463, typos could be avoided when a new PR gets merged.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
/sig testing
/area test-infra
/sig release
/cc @ixdy
/assign @fejta
**Release note**:
```release-note
None
```
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Abstract some duplicated code in the iptables proxier
Reorganizes the iptables proxier code so we only have the list of "-A FOO -j KUBE-BAR" rules in one place rather than duplicating the same list in multiple places. Split out from #56164 for ease of review/merging.
**Release note**:
```release-note
NONE
```
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validate ipset set and entry - ipvs proxier validate entry before adding it and validate set before creating it
**What this PR does / why we need it**:
validate ipset util.
**Which issue(s) this PR fixes**:
Fixes#57269
**Special notes for your reviewer**:
I splitted this PR into some small pieces for the sake of code review.
**Release note**:
```release-note
NONE
```
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Add kubeproxyconfig round trip test
**What this PR does / why we need it**:
This is a follow-up of https://github.com/kubernetes/kubernetes/pull/55961.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
ref: #55959
**Special notes for your reviewer**:
/cc @luxas @mtaufen @ncdc
**Release note**:
```release-note
NONE
```
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kube-proxy: fix field name comments & json tags
**What this PR does / why we need it**: correct some minor issues in the comments and json tags for some of the fields in the kube-proxy config structs.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
The udpTimeoutMilliseconds field in the kube-proxy configuration file has been renamed to udpIdleTimeout. Action required: administrators need to update their files accordingly.
```
This was extracted from my currently unmerged f074b28fe9, as requested [here](https://github.com/kubernetes/kubernetes/pull/52198#pullrequestreview-85538637).
@kubernetes/sig-network-pr-reviews @luxas
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Initialize IPVS proxy OWNERS file
**What this PR does / why we need it**:
Initialize IPVS proxy OWNERS file. There are 3 initial members: @thockin, @brendandburns and me :)
@thockin and @brendandburns has reviewed most of the IPVS proxier PRs.
I initialized this package and authored most of the commits.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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make ipvs 'cleanupIptablesLeftovers' simplier
Since there are only four iptables chains in ipvs mode, no need to restore all chains when cleanup iptables chain created by ipvs.
**What this PR does / why we need it**:
Make ipvs `cleanupIptablesLeftovers` function much simplier.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#56689
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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Ignore address not exist error when unbind IPVS serivce address from dummy device
**What this PR does / why we need it**:
Ignore address not exist error when unbind IPVS serivce address from dummy device.
**Which issue(s) this PR fixes**:
Fixes#58681
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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add more ipv6 support in userspace proxier
Signed-off-by: Ma Shimiao <mashimiao.fnst@cn.fujitsu.com>
**What this PR does / why we need it**:
format `%s:%d/%s"` is not suitable for ipv6 IP, replace with net.JoinHostPort
**Release note**:
```release-note
None
```
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Fix nodeport localhost martian source error
**What this PR does / why we need it**:
kube-proxy NodePort access via localhost, with externalTrafficPolicy=Local will trigger martian source error.
This PR fixes nodeport localhost martian source error.
**Which issue(s) this PR fixes**:
Fixes#57922
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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Remove ExternalTrafficLocalOnly from kube_feature gate
*What this PR does / why we need it**:
This PR is for v1.10.
External Source IP Preservation (ESIPP) had been promoted to GA since 1.7. Following the proposal on https://github.com/kubernetes/kubernetes/issues/46404#issuecomment-303939180, we should be able to remove it from feature gate now.
Added release note to announce this.
Also ref the previous attempt: https://github.com/kubernetes/kubernetes/pull/45857.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#56645
**Special notes for your reviewer**:
**Release note**:
```release-note
"ExternalTrafficLocalOnly" has been removed from feature gate. It has been a GA feature since v1.7.
```
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fix ipvs proxy mode kubeadm usage
**What this PR does / why we need it**:
Fix ipvs proxy mode usage of kubeadm in ipvs README file.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Release note**:
```release-note
NONE
```
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Fix windows UT for proxy mode
**What this PR does / why we need it**:
/kind bug
Fix windows UT for proxy mode.
Run UTs for `kubeproxyconfig/validation` in windows,
```
=== RUN TestValidateKubeProxyConfiguration
--- FAIL: TestValidateKubeProxyConfiguration (0.00s)
validation_test.go:83: expected success: [KubeProxyConfiguration.Mode.ProxyMode: Invalid value: "ipvs": must be kernelspace,userspace or blank (blank means the most-available proxy [currently userspace])]
```
That's because proxy mode "IPVS" is not valid in windows.
**Which issue(s) this PR fixes**:
Fixes#58037
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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add "Not Found" error for ipset set & entry delete
**What this PR does / why we need it**:
Add "not found error" for ipset set and entry delete. For example,
```
[root@SHA1000130405 k8s-yml]# ipset list
Name: KUBE-LOOP-BACK
Type: hash:ip,port,ip
Revision: 2
Header: family inet hashsize 1024 maxelem 65536
Size in memory: 16776
References: 1
Members:
172.17.0.2,udp:53,172.17.0.2
172.17.0.2,tcp:53,172.17.0.2
100.106.89.164,tcp:6443,100.106.89.164
[root@SHA1000130405 k8s-yml]# ipset delete foo
ipset v6.19: The set with the given name does not exist
[root@SHA1000130405 k8s-yml]# ipset del KUBE-LOOP-BACK 1.2.3.4,tcp:80,1.2.3.4
ipset v6.19: Syntax error: Third element is missing from 1.2.3.4,tcp:80,1.2.3.4.
```
Just need to filter the error message "does not exist" or "element is missing". We should ignore these error when try to make sure they are deleted.
**Which issue(s) this PR fixes**:
Fixes#57318
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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Update gengo version to include goimports formatter
Update gengo which now uses goimports to format code and organize imports.
Fixes#55542
**Special notes for your reviewer**:
Updates version of k8s.io/gengo
Takes new dependency on golang.org/x/tools/imports and golang.org/x/tools/go/ast/astutil
**Release Notes**:
```release-note
NONE
```
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Fix ipvs virutal server update
**What this PR does / why we need it**:
Fix ipvs virutal server update.
**Which issue(s) this PR fixes**:
Fixes#57698
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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fix the problem that kube-proxy can't create clusterIP ipvs rules when externalTrafficPolicy=Local
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes#57678
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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replace syscall with sys/unix pkg in ipvs/netlink call
**What this PR does / why we need it**:
This PR replaces syscall with sys/unix pkg in ipvs/netlink call as the Go doc for syscall says:
NOTE: This package is locked down.
Code outside the standard Go repository should be migrated to use the corresponding package in the golang.org/x/sys repository.
That is also where updates required by new systems or versions should be applied.
See https://golang.org/s/go1.4-syscall for more information.
**Which issue(s) this PR fixes**:
Fixes #57430
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
/assign @thockin @brendandburns
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Fix ipvs proxier nodeport
**What this PR does / why we need it**:
Fix ipvs proxier nodeport.
**Which issue(s) this PR fixes**:
Fixes#55923
**Special notes for your reviewer**:
We bump the netwlink version in the 1st commit because:
* We call `netlink.RouteListFiltered()` to filter LOCAL type addresses from kernel route table. `netlink.RouteListFiltered()` exists in newer-version netlink package
* newer-version netlink package migrate `syscall` to `golang.org/x/sys/unix`, k8s cross-build can benefit from it as well. The Go doc for syscall says:
> NOTE: This package is locked down. Code outside the standard Go repository should be migrated to use the corresponding package in the golang.org/x/sys repository. That is also where updates required by new systems or versions should be applied. See https://golang.org/s/go1.4-syscall for more information.
**Release note**:
```release-note
Fix ipvs proxier nodeport eth* assumption
```
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Enhance proxy mode validation
**What this PR does / why we need it**:
Proxy modes are list multiple times in validateProxyModeWindows and validateProxyModeLinux. This PR enhances the validation logic and only list them once.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Refer https://github.com/kubernetes/kubernetes/pull/56529/files#r156448205.
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
/assign @thockin
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Remove dead code in winkernel proxy UT
**What this PR does / why we need it**:
There is a `+build windows` tag in `pkg/proxy/winkernel/proxier_test.go`, it means the UTs will not run in upstream CI. Plus, the UT codes in `pkg/proxy/winkernel/proxier_test.go` are not for winkernel proxier, instead they are for iptables proxier!
We should remove the dead code in winkernel proxy UT and then create the winkernel-specific UTs.
**Which issue(s) this PR fixes**:
Fixes#56555
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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Test Proxy Mode
**What this PR does / why we need it**:
Currently, IPVS-based kube-proxy is protected by feature gateway and there is no UT for it. We should test ipvs proxy mode when feature gateway is set.
**Which issue(s) this PR fixes**:
Fixes#56404
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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Validate IPVSConfiguration only when IPVS mode is enabled.
**What this PR does / why we need it**:
It's strange for users that they should configuration valid values for ipvs params even when they don't use ipvs mode. Users don't need to care about these params in this case.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
/cc @m1093782566
**Release note**:
```release-note
NONE
```
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remove dead code
**What this PR does / why we need it**:
remove dead code in IPVS kube-proxy
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
/assign @thockin
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Update IPVS README
**What this PR does / why we need it**:
People complained that they feel confused about how to use IPVS-based kube-proxy correctly, probably we may need to provide them a better README.
**Which issue(s) this PR fixes**:
xref: #56319
**Special notes for your reviewer**:
**Release note**:
```release-note
NONE
```
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Fixed typo in IPVS documentation
**What this PR does / why we need it**:
Fixed documentation typo
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #
**Special notes for your reviewer**:
**Release note**:
```release-note
Fixed documentation typo in IPVS README.
```
