docs/security-and-lb: illustrate topologies with images

[hagen1778]

This change illustrates common vmauth topologies with simple excalidraw diagrams. Some of them could have been mermaid diagrams, but more complicated topologies looked not good in mermaid. So I decided to keep it consistent within the same excalidraw style.

Follow-up after #1098 (comment)

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@TomFern I request your review on this PR for the following reasons:

1. My illustrations could be far from ideal and I believe in your skills on making them more clear for users
2. Other examples in this doc may require similar illustrations. I only addressed required in docs: replace some mermaid charts with excalidraw #1098 (comment)
3. I'd like you to be involved and start maintaining diagram style across the docs in VM-related projects. These excalidraw diagrams were made based on the common VM library. You can find the full reference here (requires Exc+).

[cubic-dev-ai]

No issues found across 10 files

_{Re-trigger cubic}

[TomFern]

@hagen1778 I'm working on the diagrams, but it will take some time. I think we should only work tidying up the images modified in this PR and open another PR if additional images need converting to excalidraw.

[vadimalekseev]

Are we sure that every user will understand curl flags like -u and -H? 😁
Probably it is better to just use username, without password and route details, like:

frontend-logs-viewer -> vmauth --{service=frontend-logs}--> victorialogs
mobile-logs-viewer -> vmauth --{service=mobile-logs}--> victorialogs
audit-logs-viewer -> vmauth --(no filters enforced)--> victorialogs

I think the config above this diagram makes the details clear enough. The diagram itself should just show high-level routing without the extra details

[TomFern]

I'll change the text as suggested and we can see how it looks. If we're not convinced we can change it further.

[vadimalekseev]

This diagram shows a tenant assignment based on request path. But the config above assigns a tenant based on Basic auth credentials.

[TomFern]

@hagen1778 @vadimalekseev I've updated the diagrams. The last one is the one I modified most, to keep with the general layout of the previous ones.

[hagen1778]

Thanks for making images nicer @TomFern !

[valyala]

@hagen1778 , @TomFern , why the *.excalidraw sources for the added images are missing in this commit? This may complicate maintenance of these images in the future when these images will require some changes.

P.S. If you use AI tools for preparing your work, please verify carefully all the output generated by AI before submitting a pull request, since AI tools still generate garbage in ~20% of cases.

[hagen1778]

@hagen1778 , @TomFern , why the *.excalidraw sources for the added images are missing in this commit? This may complicate maintenance of these images in the future when these images will require some changes.

The source is provided as single file that contains all diagrams - see https://github.com/VictoriaMetrics/VictoriaLogs/blob/535d523c0575c900827ba757631a2d496f2c429c/docs/victorialogs/security-and-lb.excalidraw. I did this to simplify management of too many files. The source file is named after the document name, so it should be easy to locate and update if needed.

If you use AI tools for preparing your work, please verify carefully all the output generated by AI before submitting a pull request, since AI tools still generate garbage in ~20% of cases.

Sure! Thanks for bringing it! I think if I'd use AI those images would look better :) But it is just me for now.

[hagen1778]

Comments were addressed. @vadimalekseev @valyala I'd appreciate one more review.