Update documentation for custom error pages

[antoineco]

Fixes #2613

@aledbf requires a new build of the custom-error-pages image.

[codecov-io]

Codecov Report

Merging #2630 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2630   +/-   ##
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  Coverage   40.74%   40.74%           
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  Files          75       75           
  Lines        5117     5117           
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  Hits         2085     2085           
  Misses       2753     2753           
  Partials      279      279

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[aledbf]

@antoineco please remove the file nginx-custom-errors.yaml and refer to the deploy guide instead.

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[antoineco]

/assign @aledbf

[aledbf]

Merging. Change in docs and the image is not testes in CI

[aledbf]

@antoineco thanks!

[aledbf]

@antoineco images are already available.

[bwolfehcm]

Hi,
Can someone tell me how to add a custom error page to the ingress controller. The documentation isn't clear on how to do this. It seems that I have to build a custom image to replace the default-backend.

[antoineco]

@bwolfehcm you may have more chances finding help on Slack than in an issue closed 2 years ago, but yes, that's correct, you have to build your own backend. This could be a webserver serving static assets, or the backend of your choice (a Go application in the example).