MGMT-19927: Modify MTU Check to Only MTUs != 1500

[linoyaslan]

This PR updates the MTU check to apply only to MTUs != 1500. Additionally, it adjusts the header subtraction to account only for IPv4/IPv6 headers.

/cc @zaneb @AlonaKaplan

[openshift-ci-robot]

@linoyaslan: This pull request references MGMT-19927 which is a valid jira issue.

Warning: The referenced jira issue has an invalid target version for the target branch this PR targets: expected the task to target the "4.19.0" version, but no target version was set.

In response to this:

This PR updates the MTU check to apply only to MTUs greater than 1500. Additionally, it adjusts the header subtraction to account only for IPv4/IPv6 headers.

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[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: linoyaslan

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[openshift-ci-robot]

@linoyaslan: This pull request references MGMT-19927 which is a valid jira issue.

Warning: The referenced jira issue has an invalid target version for the target branch this PR targets: expected the task to target the "4.19.0" version, but no target version was set.

In response to this:

This PR updates the MTU check to apply only to MTUs greater than 1500. Additionally, it adjusts the header subtraction to account only for IPv4/IPv6 headers.

/cc @zaneb @AlonaKaplan

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the openshift-eng/jira-lifecycle-plugin repository.

[openshift-ci-robot]

@linoyaslan: This pull request references MGMT-19927 which is a valid jira issue.

Warning: The referenced jira issue has an invalid target version for the target branch this PR targets: expected the task to target the "4.19.0" version, but no target version was set.

In response to this:

This PR updates the MTU check to apply only to MTUs != 1500. Additionally, it adjusts the header subtraction to account only for IPv4/IPv6 headers.

/cc @zaneb @AlonaKaplan

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the openshift-eng/jira-lifecycle-plugin repository.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 60.70%. Comparing base (3e2184b) to head (547cbdb).
Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #910      +/-   ##
==========================================
+ Coverage   60.52%   60.70%   +0.17%     
==========================================
  Files          75       75              
  Lines        4008     4044      +36     
==========================================
+ Hits         2426     2455      +29     
- Misses       1411     1417       +6     
- Partials      171      172       +1     

Files with missing lines	Coverage Δ
src/connectivity_check/mtu_checker.go	63.26% <100.00%> (+5.12%)	⬆️

... and 1 file with indirect coverage changes

[zaneb]

LGTM. I assume you have tested this locally with a non-default MTU? I expect none of the CI jobs are exercising it.

[linoyaslan]

LGTM. I assume you have tested this locally with a non-default MTU? I expect none of the CI jobs are exercising it.

@zaneb Yes, I tested it locally using stat-net to configure interfaces with MTU < 1500 and MTU > 1500. I set the switch MTU smaller than the hosts' interfaces MTU. The validation failed for all hosts as expected. I started the installation despite the validation failure, and it timed out—similar to what was described in the original ticket, as expected.

[linoyaslan]

/retest

[linoyaslan]

/retest

[AlonaKaplan]

/lgtm

[openshift-ci-robot]

/retest-required

Remaining retests: 0 against base HEAD 3e2184b and 2 for PR HEAD 547cbdb in total

[linoyaslan]

/retest

[linoyaslan]

/test okd-scos-e2e-aws-ovn

[openshift-ci-robot]

/retest-required

Remaining retests: 0 against base HEAD 93697bb and 1 for PR HEAD 547cbdb in total

[openshift-ci-robot]

/retest-required

Remaining retests: 0 against base HEAD 93697bb and 2 for PR HEAD 547cbdb in total

[openshift-ci]

@linoyaslan: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/e2e-agent-compact-ipv4	547cbdb	link	true	/test e2e-agent-compact-ipv4
ci/prow/okd-scos-e2e-aws-ovn	547cbdb	link	false	/test okd-scos-e2e-aws-ovn

Full PR test history. Your PR dashboard.

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