Azure-docs: X-Original-Host does not work on Application Gateway v2

[ecaron]

Per ticket 118101521001417, X-Original-Host isn't available for Application Gateway SKU V2. Please update the documentation to call that out.

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Document Details

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• ID: 88466307-81b8-1e5b-7f2c-191d8e818071
• Version Independent ID: 08ad49f3-6a57-b925-794a-37215e985aba
• Content: Frequently asked questions for Azure Application Gateway
• Content Source: articles/application-gateway/application-gateway-faq.md
• Service: application-gateway
• GitHub Login: @vhorne
• Microsoft Alias: victorh

[TravisCragg-MSFT]

@ecaron Thanks for the feedback! I have assigned the issue to the content author to evaluate and update as appropriate.

[vhorne]

@ecaron
This is a bug and the product team is working on a fix.

[michaeljfazio]

Isn't the real bug here the fact that Application Gateway does not support the de-fact X-Forwarded-Host header?

A great deal of software using X-Forwarded-Host and will not work behind proxy services that do not implement it. X-Original-Host is far far less supported.

[pierslawson]

@vhorne can you provide a link to the issue so we can see when it is fixed?

[vhorne]

@pierslawson

Looks like the product team is shooting for early January.

[Jaffacakes82]

@vhorne do you happen to have an update and is this broken on the WAF V1 tier too?

This is pretty critical stuff! Is there another GitHub issue tracking the fix?

Agree with @michaeljfazio - can't we have the standard header for this as per this feedback request?

EDIT: That header does work on WAF V1.

[georgievaja]

Hi, this is a real blocker - gateway is not usable for us now. I also agree you should make at least choosable to use standard X-Forwarded-Host header. I do not like the idea of rewriting all the middlewares which count on X-Forwarded-Host to use X-Original-Host instead.

[JinseGeerts]

@vhorne Any update on this one?

[vhorne]

@ecaron Fix should be live in about 2 weeks.

[jimothyGator]

@vhorne To clarify, will the fix include theX-Forwarded-Host header?

In the meantime, is it possible to add a custom header to an existing AppGateway rule? I attempted to follow the instructions here, but ran into an issue running the commands in that article (#22944)

[milope]

I have to agree with everyone else on the X-Forwarded-Host header. It really is the de-facto header many middleware services expect from reverse proxies.

[animetauren]

The solution should not be that the customer has to manually rewrite the headers to add the X-Forwarded-Host header. The AppGW should include this header natively especially in V2, as a way to avoid save customers many hours/days of troubleshooting.

[vhorne]

@ecaron X-Original-Host is now available for Application Gateway SKU v2.

please-close

[JinseGeerts]

@vhorne Do we need to do a manual update now? Cause I'm still not seeing the header.