80021: Account-wide connection creation rate exceeded

A connection was refused because new connections were being opened across the account faster than the permitted rate. The limit applies to the account as a whole rather than to any single connection.

What you should do

If the connection is needed, retry it after a short delay, increasing the delay if it is refused again. This limit applies to your account's total rate of opening new connections, so opening them from more clients does not help: every new connection in the account counts towards it. If your account consistently needs to open connections faster, you can request a higher limit.

Why it happens

Your account has a maximum rate at which new connections can be opened across all of its apps, set by your account's limits. This is about how quickly connections are opened, not how many are open at once. When new connections are opened faster than the permitted rate, further attempts are refused until it falls back within the limit.

What you'll see

The connection is refused. The error is reported with code 80021 and HTTP status 429, with a message of the form Maximum account-wide instantaneous connections rate exceeded; permitted rate = ...; metric = connections.maxRate.