A link can also display a status of degraded when the site that receives replicated data is unable to quickly commit the data to the database. This behavior happens when large volumes of data replicate.
Database replication thresholds
Database replication thresholds define when Configuration Manager reports the status of a database replication link as either degraded or failed. By default, it sets a link as degraded when any one replication group fails to complete replication for 12 consecutive attempts. It sets the link as failed when any replication group fails to replicate in 24 consecutive attempts.
Question 10 of this post might be helpful to you.
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Mikey Qiao
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