The old metadata format looked like this:

(WiredTigerCheckpoint.1=(...))\n
timestamp=hhhh

After refactoring the layered connection code ( WT-16381 ) , metadata format changed to:

checkpoint=(WiredTigerCheckpoint.1=(...)),
timestamp=hhhh,
key_provider=(...)

Where key_provider=(...) settings are optional.

Changes:

1. Entire record is following config format, i.e., key=value pairs, comma-separated
2. Checkpoint data has checkpoint= key.
3. New lines are optional.

The problem:
The new code cannot read old metadata format.

Solution:

• Implement backward compatibility for reading old metadata format.
• Write in new format only (current behaviour).