Helix Core Server Administrator Guide: Fundamentals (2019.2)

Side-track servers must have the same db.peeking level

A single Helix server instance can detect and ignore inadvertent attempts to override db.peeking that would change table locking order and risk deadlock.

For example, if you attempt to use db.peeking=3 on a server for which peeking is disabled ( db.peeking is set to 0 or unset), the attempt is ignored.

However, this protection is not available with the "side-track servers" described in the Support Knowledgebase article,"Setting Up a 'Side-track' Server to Control Priority".

Warning

All side-track servers must have the same db.peeking setting as the main server or server deadlock might occur.