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Forum Discussion

Abu_Bakar_Afzal's avatar
Abu_Bakar_Afzal
Icon for Altostratus rankAltostratus
Mar 31, 2022

SMTP VS is resetting the after 3 way handshake

We are facinig TCP reset from F5 VIP towards client after completing 3 way handshake. Can anyone support on this?
application delivery
BigIP F5 LTM SMTP
JoshBecigneul's avatar
JoshBecigneul
Icon for MVP rankMVP
Mar 31, 2022

Hi Abu_Bakar_Afzal,

I have a few suggestions to try to check:

  • Which type of VS are you using? ie: Standard vs FastL4.
  • Verify which tcp profile is in use, and consider swapping it to a "lan" or "wan" variant.
  • Is any SMTP profile in use?
  • Is the connection between the BIG-IP and the SMTP server busy, high latency, or otherwise congested?
  • Abu_Bakar_Afzal's avatar
    Abu_Bakar_Afzal
    Icon for Altostratus rankAltostratus
    Mar 31, 2022

    Hi,

    VS is Standard and we are using default SMTP profile. Connection is not even used its new deployement.