Networker: Twinning enabled on the Sybase database causes DD stream exhaustion

• NetWorker backups are configured for a Sybase backup with twinning enabled.
• DD stream rise to hundred/thousand once the twining job is spawned.
• The primary Data Domain shows a moderate number of DD write streams with the number fluctuating up and down.
• The Secondary Data Domain shows an excessive number of write streams. The write stream count is only increasing (it does not go down).
  
  • The following Data Domain commands are used on each Data Domain to determine this symptom is occurring during Sybase backups:
    • mtree list
    • ddboost storage-unit show
    • ddboost streams show active storage-unit STORAGE-UNITNAME

Where STORAGE-UNITNAME is the storage-unit where the Sybase backups are writing. 

This issue was raised to NetWorker engineering.

This issue is addressed in the following NetWorker releases:

• 19.12.0.3
• 19.13.0.1

Upgrade to one of the above releases or later for a code fix.