Reduce support cases: Connection limits

[ejizba]

Generally the user is creating too many connections and the solution is to use connection pooling.

Support cases from June 2023 - Sept 2023

Internal-only links:

• https://elixir.microsoft.com/case-review/2307100060000536
• https://elixir.microsoft.com/case-review/2307110030004170

[timtucker-dte]

Looks like documentation is out of date here:

Because it provides better connection management options, you should use the native http.agent class instead of non-native methods, such as the node-fetch module.

Newer versions of node now include support for the Fetch API built-in, so it's no longer a question of "native" vs. "non-native".

[timtucker-dte]

The "SqlClient connections" section could use some examples for JavaScript / TypeScript.

ms-sql as a package supports connection pooling, but it's difficult to find example code for how to best establish connections when running Azure Functions so that the pool can recover from errors that may occur outside across function executions.

[timtucker-dte]

Something that isn't mentioned very clearly in documentation -- not having enough IPs assigned within a vnet for Azure Functions can result in very similar symptoms to hitting connection limits.