hybrid-mode version-compatibility page has misleading information

[srb3]

Where is the problem?

https://docs.konghq.com/gateway/2.8.x/plan-and-deploy/hybrid-mode/#version-compatibility

What happened?

When describing kong version compatibility the following wording is used:

Kong Gateway control planes only allow connections from data planes with the same major version. Control planes won’t allow connections from data planes with newer minor versions.

For example, a Kong Gateway v2.5.2 control plane:

Accepts a Kong Gateway 2.5.0, 2.5.1 and 2.5.2 data plane.
Accepts a Kong Gateway 2.3.8, 2.2.1 and 2.2.0 data plane.
Accepts a Kong Gateway 2.5.3 data plane (newer patch version on the data plane is accepted).
Rejects a Kong Gateway 1.0.0 data plane (major version differs).
Rejects a Kong Gateway 2.6.0 data plane (minor version on data plane is newer).

This suggests that a kong CP running a higher minor version than a DP should be compatible.

Then a bit later when describing the log lines one might see with a compatibility issue:

If a config can not be pushed to a data plane due to failure of the compatibility checks, the control plane will contain warn level lines in the error.log similar to the following:

unable to send updated configuration to DP node with hostname: localhost.localdomain ip: 127.0.0.1 reason: version mismatches, CP version: 2.2 DP version: 2.1

In this log example the CP and DP are both the same major version and the CP has a higher minor version. So they should be compatible.

What did you expect to happen?

It might be more accurate to change the log line to this:

unable to send updated configuration to DP node with hostname: localhost.localdomain ip: 127.0.0.1 reason: version mismatches, CP version: 2.2 DP version: 2.3

or this

unable to send updated configuration to DP node with hostname: localhost.localdomain ip: 127.0.0.1 reason: version mismatches, CP version: 3.2 DP version: 2.1

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[lena-larionova]

@fffonion can you please clarify if the doc on hybrid mode version compatibility is correct, or if the log message should be fixed?