90010: Too many channels

An operation was rejected because it would exceed the maximum number of channels permitted, either the channels attached to a single connection or those included in a single batch request.

What you should do

If you hit the per-connection limit, detach channels the connection no longer needs; the usual cause is channels that are attached and then never explicitly detached. If you hit it on a batch publish or batch presence request, reduce the number of channels included in a single request. If your use case genuinely needs more, contact Ably support to raise the limit.

Why it happens

The operation would exceed a maximum number of channels. This applies in two places: the number of channels attached to a single connection, and the number of channels included in a single batch publish or batch presence request. Both limits are set by the account.

What you'll see

The error is reported with code 90010 and HTTP status 400. The messages include Maximum number of channels per connection (<n>) exceeded, Max number of channels permitted in a single bulk publish request (<n>) exceeded, and Max number of channels permitted in a single batch presence request (<n>) exceeded.