Cannot create cursors in hot standby replica nodes

[tomas-fp]

I'm querying a large dataset using cursors. I can do it properly with against a master node, but if I run against a hot standby replica node I'm getting the following error:

asyncpg.exceptions.FeatureNotSupportedError: cannot use serializable mode in a hot standby

Is it possible to run cursors against replica nodes?
How the hot standby affects this?

Environment:

• Python v3.6.0
• asyncpg v0.8.4
• PostgreSQL v9.4

[elprans]

Please provide some example code that triggers this. From your description it looks like you are trying to use transaction(isolation='serializable') on a standby node.