cluster: support RHEL8

[nexustar]

What problem does this PR solve?

• close Tiup support to deploy tidb 6.1 on Red hat enterprise linux 8 #1887

What is changed and how it works?

I do not know why,but it works.Perhaps that's been the story of SELinux

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

Code changes

• Has exported function/method change
• Has exported variable/fields change
• Has interface methods change
• Has persistent data change

Side effects

• Possible performance regression
• Increased code complexity
• Breaking backward compatibility

Related changes

• Need to cherry-pick to the release branch
• Need to update the documentation

Release notes:

NONE

[ti-chi-bot]

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• srstack

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[AstroProfundis]

If we suggest users to disable SELinux in check, I think it's okay not to workaround it.

Beside, is it possible to add new SELinux rules to allow TiDB components? Will it be too complex?

[codecov-commenter]

Codecov Report

Merging #1896 (2408749) into master (5a9c0b3) will increase coverage by 4.24%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #1896      +/-   ##
==========================================
+ Coverage   47.46%   51.70%   +4.24%     
==========================================
  Files         307      307              
  Lines       35454    35454              
==========================================
+ Hits        16825    18329    +1504     
+ Misses      16643    14944    -1699     
- Partials     1986     2181     +195     

Flag	Coverage Δ
cluster	39.96% <0.00%> (+7.04%)	⬆️
dm	24.41% <0.00%> (ø)
playground	12.91% <ø> (ø)
tiup	14.45% <ø> (ø)
unittest	21.03% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
pkg/cluster/operation/check.go	48.22% <0.00%> (+48.22%)	⬆️
pkg/cluster/operation/scale_in.go	39.74% <0.00%> (-15.38%)	⬇️
pkg/cluster/task/update_meta.go	72.04% <0.00%> (-12.90%)	⬇️
pkg/cluster/task/task.go	64.81% <0.00%> (-8.33%)	⬇️
pkg/cluster/manager/builder.go	66.56% <0.00%> (-6.53%)	⬇️
pkg/cluster/manager/destroy.go	51.22% <0.00%> (-4.07%)	⬇️
pkg/cluster/task/step.go	64.94% <0.00%> (-3.90%)	⬇️
pkg/tui/progress/single_bar.go	84.78% <0.00%> (-3.26%)	⬇️
pkg/cluster/spec/tiflash.go	66.67% <0.00%> (-2.01%)	⬇️
pkg/cluster/spec/tidb.go	62.59% <0.00%> (-1.44%)	⬇️
... and 64 more

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[nexustar]

If we suggest users to disable SELinux in check, I think it's okay not to workaround it.

Beside, is it possible to add new SELinux rules to allow TiDB components? Will it be too complex?

need to run sudo chcon -t bin_t /tidb-deploy/pd-2379/scripts/run_pd.sh for all component.Since not all systemd has SELinux,it may be too complex to add it to tiup-cluster code.If user do not accept disabling SELinux,he will need to use tiup cluster exec and 2-step scale-out.So I think we should use workaround in this PR

[AstroProfundis]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 2408749