TFTP Error Packet

The TFTP ERROR packet is used to notify a problem during data transmission or when a TFTP connection cannot be established. The format of TFTP ERROR packet is as shown below.


Following are the fields of TFTP DATA packet.

  • Opcode : Opcode field of TFTP ERROR packet is 16-bits (2-bytes) in length. TFTP ERROR packets have an opcode value of "5".

  • Error Code : The error code of TFTP ERROR packet is an integer showing the type of the error. Following table lists the possible values of error code of TFTP ERROR packet.

  • Error Code Meaning
    0 Not defined
    1 File not found
    2 Access Violation
    3 Disk full or Quota exceeded
    4 Illegal TFTP operation
    5 Unknown port number
    6 File exists
    7 No such user

  • Error Message : Error Message field of the TFTP ERROR packet is a variable size field. Error Message field is a human readable field and is in ASCII.

  • All 0s : The TFTP ERROR packet is terminated with one byte of all zeros.

Following image shows a Wireshark packet capture screeshot of TFTP ERROR packet.


Related Tutorials
What is TFTP (Trivial File Transfer Protocol)
Important RFCs related with TFTP
Difference Between FTP and TFTP
TFTP Message Types
TFTP RRQ (Read Request) packet
TFTP WRQ (Write Request) packet
TFTP Data Packet
TFTP ACK (Acknowledge) Packet
TFTP Client and TFTP Server
How TFTP works