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Packet-Logger

Packet Logging in TazUO

Section titled “Packet Logging in TazUO”

TazUO includes built-in packet logging functionality to capture network traffic between the client and server. This is useful for debugging, development, and understanding the UO networking protocol.

Enabling Packet Logging

Section titled “Enabling Packet Logging”

Command Line Option

Section titled “Command Line Option”

Use the -packetlog command line argument to enable packet logging:

Terminal window
TazUO.exe -packetlog

Selective Packet Logging

Section titled “Selective Packet Logging”

You can log specific packet IDs by providing a comma-separated list:

Terminal window
# Log only specific packet IDs (hexadecimal)
TazUO.exe -packetlog 0x1A,0x20,0x77


# Multiple packet IDs without 0x prefix
TazUO.exe -packetlog 1A,20,77


# Mix of formats (both work)
TazUO.exe -packetlog 0x1A,20,0x77

Log File Location

Section titled “Log File Location”

Packet logs are saved to:

<TazUO Directory>/Logs/Network/packets.log

The log directory is automatically created if it doesn’t exist.

Log Format

Section titled “Log Format”

Header Information

Section titled “Header Information”

Each logged packet includes:

  • Timestamp: Current time when packet was captured
  • Direction: Either “Client -> Server” or “Server -> Client”
  • Packet ID: Hexadecimal packet identifier (first byte)
  • Length: Total packet size in bytes

Hex Dump Format

Section titled “Hex Dump Format”
Time: 14:30:25 | Client -> Server |  ID: 02   Length: 7
         0  1  2  3  4  5  6  7   8  9  A  B  C  D  E  F
         -- -- -- -- -- -- -- --  -- -- -- -- -- -- -- --
00000000  02 00 07 00 01 00 00                              .......

Security Features

Section titled “Security Features”

Account Credential Protection

Section titled “Account Credential Protection”
  • Packets 0x80 (Account Login) and 0x91 (Game Server Login) are automatically filtered
  • Shows [ACCOUNT CREDENTIALS HIDDEN] instead of packet contents
  • Credentials are only logged if explicitly requested: -packetlog 0x80,0x91

Technical Details

Section titled “Technical Details”

Key Features

Section titled “Key Features”
  • Selective Logging: Filter by specific packet IDs
  • Real-time Writing: Packets are immediately written to disk
  • ASCII Representation: Shows printable characters alongside hex data
  • Memory Efficient: Uses stack-allocated buffers for formatting

Common Use Cases

Section titled “Common Use Cases”

Development and Debugging

Section titled “Development and Debugging”
Terminal window
# Log all packets
TazUO.exe -packetlog


# Debug movement packets
TazUO.exe -packetlog 0x02,0x22
- Logging all packets can generate large files quickly during active gameplay
- Use selective logging for specific debugging scenarios
- Account credentials are protected by default for security
- Log files persist between sessions and are not automatically rotated