Broken DG configuration

Few days ago I 've run into the following situation on a DG configuration:

• the primary shipped logs to the standby properly, but reported errors if asked for status in dgmgrl

  DGMGRL> show configuration
  
  Configuration - dbd
  
    Protection Mode: MaxPerformance
    Databases:
      db1d - Primary database
      db2d - Physical standby database
  
  Fast-Start Failover: DISABLED
  
  Configuration Status:
  ORA-16610: command "Broker operation" in progress
  DGM-17017: unable to determine configuration status
  

• the standby initially did not process archivelogs, but after configuration reset (disable and enable operations) it started to process them, but also reported errors in dgmgrl
• it was possible to log in from the primary to the standby
• it was possible to log in from the standby to the primary
• I copied password file from the primary to the standby to ensure this is the same file
• when calling show database on the primary the errors were reported for the standby
• when calling show database on the standby the errors were reported for the primary

What was the cause?
It showed that the problem was generated by the TNS entries on the primary - apparently the TNS alias definitions for the primary and the standby there included some blank characters, which caused the alias to be read improperly in case of dgmgrl - at the same time simple call to those aliases through sqlplus went ok.
Once I removed all the formatting in the tnsnames.ora, whole thing started to work properly. What is a bit interesting is that the errors in the TNS were present only on the primary, while the dgmgrl calls malfunctioned on both ends.