Update application-gateway-faq.md

[ChrisLopezUK]

Added a small section on Connection Draining on request of a customer.

Q. Does changing backend pool members cause disruption?

[PRMerger17]

@ChrisLopezUK : Thanks for your contribution! The author, @davidmu1, has been notified to review your proposed change.

[vhorne]

@ChrisLopezUK

Hi Chris, thanks for the submission. I discussed with Amit (the App Gateway PM) and likes the idea, but would rather focus a bit more on the connection draining feature. So something more along the lines of:

Does application gateway support connection draining?

Yes. You can configure connection draining to change members within a backend pool without disruption. This will allow existing connections to continue to be sent to their previous destination until either that connection is closed or a configurable timeout expires. Note that connection draining only waits for current in-flight connections to complete. Application Gateway is not aware of application session state.

[vhorne]

See Conversation for suggested wording.

[ChrisLopezUK]

Perfect. :)

Thank you!

[vhorne]

@ChrisLopezUK

OK, go ahead and update your PR, and I'll sign-off so it gets merged. We'll probably also need a bit more supporting info about connection draining elsewhere in the content, so we'll see if we can find a place where it fits.

[ChrisLopezUK]

Hi Vic,

I am a bit of GitHub novice so I am hoping I have made the changes correctly.

Please let me know if I have done anything incorrectly.

[PRMerger13]

@ChrisLopezUK : Thanks for your contribution! The author, @davidmu1, has been notified to review your proposed change.

[vhorne]

Looks good.
#sign-off

[PRMerger8]

@vhorne: I'm sorry - only the author of this article, @davidmu1, can sign off on your changes. But we do have an exception process - if you are on the Microsoft content or product team for this product area, you can ask the PR review team to review and merge it by sending mail to the techdocprs alias.

[davidmu1]

#sign-off