DNS
11 DSOTYPENI
DSO-TYPE Not Implemented. The DNS Stateful Operations (DSO) type in the request is not supported by the server.
When You See This Code
Your client attempted a DSO operation (like a keepalive or push subscription) that the server does not recognize or has not implemented.
How to Fix
Verify that both client and server support the same DSO-TYPE. Upgrade the server software or fall back to traditional DNS queries.