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ONTAP responds with a TCP ACK when a client sends a SYN, and connection never gets established

Last Updated:

Applies to

  • Data ONTAP 7-Mode
  • Clustered Data ONTAP
  • ONTAP 9
  • TCP and any top layer protocol that client may use such as: NFS, CIFS, ISCSI


  • Client can't establish a new TCP session
  • ONTAP responds to client's SYN with only an ACK
  • Client tore down a session, but the FIN never made it to the filer
  • Client is attempting to establish a new session using the same TCP source port from the previous connection


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